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On Track

OnTrack: The Newsletter of the International Fission-Track Community

November 1996, Volume 6, Number 2, Issue 13

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Editor: Danny Stockli
Department of Geological and Environmental Sciences,

Stanford University, Stanford, California 94305-2115 USA

(danny@pangea.stanford.edu)

In this Issue:

On Track is a biannual newsletter of the inter-national fission-track community. It is printed in the months of May and November. The views expressed in On Track are those of the authors and do not necessarily reflect those of the fission-track community or the editor(s) of On Track.

Copyrights of by-lined articles belong to the authors and they may not be reproduced without written permission from the authors. Trademarks and patents are the sole property of the corporation(s) and/or individual(s) indicated in the article.

On Track will remain free, at least for the near future. However, to save costs we generally mail only one copy per lab so please be sure to pass On Track around your lab.

Printing and mailing costs for this issue of On Track were paid for by a monetary donation from Donelick Analytical, Incorporated and paid advertisements. Standard prices for full, half, and quarter page advertisements are US$ 200, US$ 100 and US$ 50, respectively. There is no charge for "short" ads by non-commercial entities (e.g., universities). Send inquiries concerning On Track to the current editor.

PREVIOUS EDITORS:

Dave Coyle (1990-91), La Trobe University

Trevor Dumitru (1991-92), Stanford University

Rasoul B. Sorkhabi (1992-93)Arizona State University

Dennis Arne (1993-94) Dalhousie University

Richard J. Weiland (1994-95) U of Texas, Austin

Ruth Siddall (1995-96) University College London

CURRENT EDITOR:

Danny Stockli (1996-97)

Department of Geological and Environmental Sciences

Stanford University

Stanford, California 94305-2115

U.S.A.

Tel.: 415-725-6155

Fax: 415-725-6155

E-mail: danny@pangea.stanford.edu


Editor's Notes

First of all I would like to thank the previous editor of On Track, Ruth Siddall, for her help during the transitional period of editorship. Issue 13 of On Track marks the seventh year of the newsletter's existence, reflecting the need and importance of On Track! The constant support and stream of requests from labs and individuals expressing their interest and wish to be added to the mailing list indicate that On Track represents a well-accepted and important forum, bringing new and interesting issues to the attention of the international FT community. On Track has always been a newsletter for the FT community by the FT community. The very existence of On Track is based on all your support and contributions. Somewhat disturbing, however, is the fact that most On Track contributions are written by a very small number of individuals from an even smaller number of research groups and laboratories, although the number fission-track labs, especially in the old world, is growing at a rather amazing rate. I would like to encourage all people and groups to contribute to On Track. I would also like to thank Ray Donelick of Donelick Analytical, Inc for his financial contributions which have permitted the continued free distribution of On Track.

In this issue, Ann Blythe presents intriguing, new data on compositional effects on zircon fission-track annealing properties. Paul O'Sullivan fills us in on the potential influences of long-term surface temperature variations on apatite FT data in Arctic environments. Two contributions in this issue deal with modeling of fission-track data. David Coyle tries to convince us that we can do almost everything using MathematicaTm, presenting a MathematicaTm notebook for modeling annealing. Dale Issler offers an inverse model for determining time-temperature histories.

After Trevor Dumitru's MEI zircon/apatite separation demonstrations at the Gent meeting, we decided to also introduce the method in On Track. As announced by Stefan Boettcher in issue 9, On Track is on the web! Dennis Trombatore of UT-Austin offered to archive electronic versions of On Track at http://www.lib.utexas.edu/Libs/GEO. Also featured in this issue is the new updated, annual fission-track directory, as well as some technical news and of course the short track news.

One copy per lab; please copy and distribute


Preliminary Note on Hf And U Concentrations and Fission-Track Annealing in Zircon

by Ann Blythe

Department of Earth Sciences, University of Southern California,

Los Angeles, California 90089-0740, USA

(blythe@earth.usc.edu)

During the recent International Fission Track conference in Gent, Belgium, a discussion occurred on the need for studies of the effects of zircon chemistry on fission-track annealing in zircon. Specifically, it was suggested that Hf (which substitutes for Zr) should be examined. In this preliminary note, I describe Hf and U concentrations from a sample that appears to have both reset and nonreset zircon fission-track ages. The sample was one of a suite of samples collected by K. Kleinspehn from the Tertiary-age Forlandsundet basin of Spitsbergen. The Forlandsundet basin rocks are considered Paleogene and younger in age, but the exact sedimentary ages of individual samples are poorly constrained. Vitrinite reflectance values of Ro = 2.55-5.07 (representing temperatures of >180deg.C) were measured near the samples used in this study (Kleinspehn and Teyssier, 1992), suggesting that partial to total annealing of fission tracks in zircon was possible. The time of peak temperatures in the basin is constrained only by apatite fission-track analyses from 32 samples collected throughout Spitsbergen. These samples ranged in age from 27 +/- 4 to 55 +/- 13 Ma, with a mean age of 37 Ma; track-length models of several of these samples (using the models of Corrigan and Gallagher) were consistent with regional cooling beginning at ~40 Ma (Blythe and Kleinspehn, in prep.).

Zircons from 6 Forlandsundet basin samples were analyzed. Four samples had zircon fission-track single grain ages ranging from 80 to 700 Ma, which, based on the probable age of deposition (Tertiary), appeared to be unreset. A single sample, PKF-688, appeared to have been totally reset, with a pooled age of 42.4 +/- 1.8 Ma. The most interesting sample, however, was PKF-49, which appeared to have a population of grains that had been reset at ~42 Ma, and a second population that had not been reset.

In Figure 1a, histograms of individual grain ages and probability distributions are shown for samples PKF-49 (reset and unreset grain ages), PKF-65 (one of the four samples with unreset ages, shown for comparison), and PKF-688 (all grains reset). Although the effects of chemical composition on fission-track annealing in apatite are well-known (e.g. Green et al., 1989), no such effects have been documented in zircon.

Frequency Age (Ma) Graph

Fig. 1a: Zircon single grain fission track age histograms and probability distributions.

Zircon [ZrSiO4] has a much simpler structure than apatite. The only major variation in chemical composition that occurs is the substitution of hafnium (Hf4+) for Zr4+. The degree of substitution can be up to 6Hf:10Zr (Phillips and Griffen, 1981), and is easily measured with a microprobe. In order to see if variations in Hf correlated to the differences in individual grain ages from PKF-49, Hf and Zr were measured on individual grains with the Cameca Microprobe at the University of California at Santa Barbara (with the assistance of D. Pierce and H. Dervin). Hf concentrations in individual grains did not vary within analytical error and no correlation between zircon fission-track age and Hf concentration was seen.

However, when I plotted U concentration versus single grain age, a distinct correlation emerged (Figure 1b). The grains with young zircon fission-track ages had higher U concentrations than grains with older ages. This correlation was apparent in PKF-49 as well as PKF-65, the sample I had initially interpreted as totally unreset, suggesting that the younger grain ages might be partially reset.

However, it should be pointed out that counting bias is a problem with these data - obviously, it is easier to count tracks in old, low-U zircons than in old, high-U zircons (too many tracks); and it is easier to count tracks in young, high-U zircons than in young, low-U zircons (too few tracks). In the Forlansundet basin samples, tracks in the young, low-U zircons could still be counted, but several of the old zircons could not be counted because the densities of spontaneous tracks were too high.

Therefore, I need to find a method for dealing with the counting bias problem with these old zircons (any suggestions would be appreciated!). I suggest that if these correlations between age and U concentration are still evident after counting bias has been eliminated, that the most likely explanation for the resetting of zircon fission-track ages involves metamictization of high-U zircons.

References Cited:

Green, P.F., Duddy, I.R., Laslett, G.M., Hegarty, K.A., Gleadow, A.J.F., Tingate, P.R., and Laslett, G.M., 1986, Thermal annealing of fission tracks in apatite: 1- a qualitative description, Isotope Geoscience, v. 59, p. 237-253.

Kleinspehn, K.L., and Teyssier, C., 1992, Tectonics of the Paleogene Forlandsundet Basin, Spitsbergen: A preliminary report, Norsk Geologisk Tidsskrift, v. 72, p. 93-104.

Philips, W.R., and Griffen, D.T., 1981, Optical Mineralogy: The Nonopaque Minerals, Freeman and Co., San Francisco, p. 131

Uranium (ppm) Zircon Age (Ma) Graphs

Fig. 1b: Plots of U concentration vs. zircon fission-track age. One sigma error bars on ages are shown.


Long-Term Change in Mean Annual Surface Temperature

and its Effect on Estimating Denudation

by Paul B. O'Sullivan

VIEPS, La Trobe University, Bundoora, Victoria, 3083, Australia

(pos@mojave.geol.latrobe.edu.au)

Introduction

The North Slope foreland basin is a late Mesozoic and Cenozoic basin that spans the entire width of northern Alaska (Fig. 1). During the Late Jurassic through Early Paleocene, denudation of the Brooks Range to the south resulted in many kilometers of material being rapidly deposited into the adjoining foreland basin. Subsequently, foreland basin rocks cooled from maximum paleotemperatures in response to km-scale denudation beginning in the Paleocene (O'Sullivan, 1996); prior to a major climatic change from temperate to arctic conditions during the late Cenozoic. Due to the lower mean annual surface temperatures resulting from the change to arctic conditions, the subsurface stratigraphy experienced significant cooling (O'Sullivan and Brown, 1996, we also have a paper ready for the FT Workshop volume but are waiting to hear whether or not they will be accepting submittals anytime soon). Therefore, since the rocks in the foreland basin cooled from maximum paleotemperatures prior to the decrease in mean annual surface temperatures, estimates of total denudation using maximum paleotemperature indicators (e.g. Ro), and present-day surface temperatures, will be overestimated.

 

Brooks Range

Figure 1: Location of the North Slope foreland basin study area showing major geographic features and wells referred to in the text, and estimated denudation of the North Slope foreland basin study area. See text for explanation.

The case study summarized here illustrates the importance of utilizing both Ro and apatite fission track thermochronology (AFTT) data when evaluating the thermal history of an area, and estimating the amount of denudation that area has experienced. As most trackers know, when assessing the thermal history of rocks, there are many uncertainties (e.g. porosity, compaction, and diagenesis associated with sedimentary basins) which are difficult to assess quantitatively in the relationship between heat flow and thermal gradient. These problems may be substantially reduced by using the method outlined by Bray et al. (1992), based on the integration of apatite fission track and vitrinite reflectance methodology, which yields a direct estimate of both the time at which cooling from maximum paleotemperatures began and the paleogeothermal gradient at that time. Furthermore, when trying to estimate maximum denudation, the time at which cooling from maximum paleotemperatures began and the surface temperature at that time are important factors to know.

One Method for Estimating Maximum Paleogeothermal Gradients and Amount of Uplift and Erosion

 

After maximum paleotemperatures are determined for AFTT and Ro samples from a vertical sequence, plotting these values relative to depth provides a maximum paleotemperature profile (Bray et al., 1992). From this profile, a paleogeothermal gradient at the time of maximum paleotemperatures can be estimated as well as the amount of section which has been removed since maximum paleotemperatures were reached. In a vertical section that has been hotter in the past, the paleogeothermal gradient can be compared to the present-day geothermal gradient, allowing interpretation of the cause of the high paleotemperatures, and the cause of the subsequent cooling to the present temperatures. Figure 2A shows a simple example where heating and subsequent cooling were caused solely by deep burial followed by denudation with no change in mean annual surface temperature or basal heat flow. In this case, the present gradient would remain the same as the maximum paleogeothermal gradient, but the paleotemperature profile trend would be translated towards higher temperatures. Therefore, the amount of removed section can be estimated by dividing the amount of cooling by the geothermal gradient.

Depth Maximum Temperature (Surface) Graphs

 

Figure 2: Hypothetical case to illustrate estimation of paleogeothermal gradients and the cause of heating and subsequent cooling from paleotemperature profiles. In each case a paleotemperature profile is shown which is similar to the present-day profile, suggesting that heat flow has not changed since maximum paleotemperatures were reached. However, the maximum profile is offset to higher temperatures indicating that the section has been hotter in the past. Therefore, heating in the past was caused by deep burial prior to cooling by denudation, and the amount of removed section can be estimated by dividing the amount of cooling by the geothermal gradient. (A) shows the simple case where mean annual surface temperatures have not changed since the time at which the section reached maximum paleotemperatures and all cooling has resulted from denudation. (B) shows the case where the mean annual surface temperature has decreased significantly since the time at which the section reached maximum paleotemperatures. In this case a component of "apparent" denudation is introduced.

Figure 2B shows a complicated example in which the mean annual surface temperature has decreased significantly since maximum paleotemperatures were reached (i.e., the North Slope foreland basin). If the surface temperature at the time the section began to cool from maximum temperatures is not known, and thus the present surface temperature is used, the amount of cooling which has occurred since maximum paleotemperatures were reached will be overestimated by a value of "apparent" denudation. The value of "apparent" denudation can be estimated by dividing the amount of cooling (difference between paleo- and present-day mean annual surface temperatures) by the geothermal gradient. The paleo-surface temperature is that which was present at the time when the subsurface section started to cool from maximum temperatures. The case shown in Figure 2B just reiterates a point which we all must keep in mind - that when calculating the amount of denudation in regions which have experienced significant changes in climate, it is important to know the time at which the climate changed, the time when cooling from maximum paleotemperatures began, and the surface temperature at that time.

Plot showing the change in temperature (DT) at depths (Z) less than 5 km through time (Dt) between 0 and 5 Ma, after a decrease in the mean annual surface temperature of ~20 degrees C. Calculations assume a geothermal gradient of ~30 degrees C/km and a thickness of the slab of ~30km. See text for details.

Plot showing the change in temperature (DT) at depths (Z) less than 5 km through time (Dt) between 0 and 5 Ma, after a decrease in the mean annual surface temperature of ~20 degrees C. Calculations assume a geothermal gradient of ~30 degrees C/km and a thickness of the slab of ~30km. See text for details.

Middle To Late Cenozoic Climatic Change and Associated Subsurface Response

As mentioned, the Cenozoic thermal history of the North Slope foreland basin is complicated because the region has experienced a significant decrease in mean annual surface temperatures, from temperate conditions in the mid-Cenozoic (~+5deg.C in the late Maastrichtian to Eocene) to present-day arctic conditions (~-12deg.C along the northern coastline). The timing of this change in climate is poorly constrained primarily due to a lack of an adequate data base, however, Clark (1990) proposed the transition of the Arctic Ocean from ice-free conditions during the early Cenozoic, to late Cenozoic arctic conditions occurred during the late Cenozoic and by late Miocene, conditions, essentially the same as exist today, were present.

In response to the drop in mean annual surface temperature accompanying the change in climate, the subsurface isotherms in time would have been repositioned downward, resulting in cooling of the stratigraphic section by a means unrelated to erosion (O'Sullivan and Brown, 1996).

In their study to determine whether a decrease in the mean annual surface temperature of the order of ~15-20deg.C could result in a noticeable change in temperatures in the subsurface, O'Sullivan and Brown formulated a simple thermal model of the lithosphere that could be described in terms of the mathematical equations describing the transfer of heat. The results of their calculations are presented graphically in Figure 3 which shows that a decrease in temperature at the surface of ~20deg.C results in a rapid (in geologic time) decrease in shallow-level (<5 km) subsurface temperatures. For example, after only 0.2 Ma, temperatures at ~2 km depth will have decreased between ~11-12deg.C, and after 5 Ma, temperatures at ~3 km depth will have decreased between ~17-18deg.C (Fig. 3).

North Slope Foreland Basin Thermal History

Previous knowledge of the North Slope thermal history was based primarily on present-day thermal profiles, measurements of organic maturation (mainly Ro, TAI, and CAI), and geothermal conditions calculated from these data. The present-day North Slope thermal regime is characterized by variable geothermal gradients; with higher geothermal gradients generally found in wells located close to the present-day coastline, and lower gradients in wells located in the foothills north of the Brooks Range. The organic maturation of rocks at the surface generally decreases northward across the North Slope; a reflection of denudation in the Brooks Range orogenic belt and subsidence and sedimentation in the adjacent foreland basin. The estimated total amount of Cretaceous and Tertiary denudation across the North Slope foreland basin, based on the position of the 0.6% and 2.0% Ro isograds, range between ~3-5 km within the foothills to ~500 m in the Inigok #1 well, to ~1 km in the region of Pt. Barrow (Howell et al., 1992).

As part of a study undertaken to determine the Cenozoic thermal history study of the North Slope foreland basin (ye' old POS PhD thesis), AFTT samples were collected from eight wells and outcrop localities across the basin. Detailed descriptions of the results and interpretations of the data were presented in O'Sullivan (1996). Results of modeling of AFTT data from 6 of 8 wells, located in the central and western

B.P. Prudhoe Bay J-1, Alaska State C-1, Husky Lisburne Test #1, Husky Tunalik Test #1

 

Figure 4: Estimated maximum paleotemperature profiles for the Lisburne Test #1, Tunalik Test #1, Prudhoe Bay J-1, and the Alaska State C-1 wells, derived from vitrinite reflectance and AFTT plotted against sample depth. The offset between maximum temperature and present temperature profiles in both the Lisburne and Tunalik wells are the result of both denudation and "apparent" denudation. Cooling recorded in the remaining two wells has been primarily in response to the Cenozoic decrease in mean annual surface change.

North Slope foreland basin (Fig. 1), suggest that the samples experienced maximum paleotemperatures, due to burial, during the Late Cretaceous to mid-Paleocene. The data also suggest that during the Tertiary, the basin subsequently experienced two episodes of rapid cooling due to denudation; during the mid-Paleocene at ~60+/-4 Ma, and during the late Oligocene at ~25+/-3 Ma. Data from two other wells, located along the present-day northern coastline between Prudhoe Bay and the Canning River (Prudhoe Bay J-1 and Alaska State C-1), also suggest rapid cooling occurred at some time <10-15 Ma. However, in contrast to the other six wells, the preserved stratigraphy within the two wells suggests that little or no section was removed during that time. Therefore, it is proposed that cooling recorded in these two wells was primarily the result of the decrease in mean annual surface temperature during the late Cenozoic.

In order to come to these conclusions, and to determine the maximum paleogeothermal gradient and amount of section removed from the section preserved in each well, maximum paleotemperatures calculated from the Ro and AFTT data were plotted against present depth (for example Fig. 4). As explained earlier, the slope of the fitted linear relationship between maximum paleotemperature and present depth provides a direct estimate of the maximum paleogeothermal gradient (maximum paleotemperature profile) prior to cooling. The "least-squares" best-fit estimates of the maximum paleogeothermal gradient for each well, derived using the maximum paleotemperature profiles, suggest the maximum paleogeothermal gradients for each well were very similar to the present-day geothermal gradients. These data indicate that the heat flow has changed little in the basin since maximum paleotemperatures were reached prior to Paleocene cooling, however in most cases, the maximum paleotemperature profile is offset towards higher temperatures as a result of previous exposure to elevated temperatures.

Since basin heat flow values have not changed much since maximum paleotemperatures were reached, but the data suggests the rocks in many of the wells experienced higher temperatures in the past, this indicates a great deal of section has been removed as a result of denudation. Therefore, the amount of removed section can be estimated by dividing the degree of cooling by the geothermal gradient. The degree of cooling is calculated by determining the maximum paleotemperature value at the present surface and subtracting the mean annual surface temperature at the time cooling from maximum paleotemperatures began. As determined from the AFTT data, cooling from maximum paleotemperatures occurred in the Paleocene. Because there has been a noticeable decrease in the mean annual surface temperature since denudation started, not all cooling experienced by the rocks from maximum paleotemperatures has been the result of denudation.

For each of the wells the calculated values of denudation and "apparent" denudation, respectively, equal (Fig. 1): ~5.3 km and ~0.4 km (Kemik #1 well); ~2.1 km and ~0.5 km (Seabee #1 well); ~1.7 km and ~0.6 km (Inigok #1 well); ~1.2 km and ~0.4 km (Walakpa #1 well); ~2.9 km and ~0.4 km (Lisburne #1 well); ~1.3 km and ~0.4 km (Tunalik #1 well); and ~0.3 km and ~0.5 km (Prudhoe Bay J-1). If the mean annual surface temperature at the time cooling started was not known, calculations of the amount of denudation would be over-estimated by an amount equal to the "apparent" denudation. In the case of the Alaska State C-1 well, no denudation has occurred, however, ~0.6 km of "apparent" denudation must have occurred in response to the decrease in the mean annual surface temperature from ~5deg.C to ~-11deg.C during the late Tertiary.

Implications

As demonstrated by many folks long before I became interested in FT (Chuck Naeser, Gunter Wagner, Paul Green, Andrew Gleadow to name a few who come to mind quickly) apatite fission track data provides a powerful method of thermal history assessment and determining amounts of denudation. In sections that have experienced higher temperatures in the past, these data allow estimation of the time at which cooling from maximum paleotemperatures began, while combined with Ro give independent estimates of maximum paleotemperatures and provide an estimate of the paleogeothermal gradient at the time of maximum paleotemperature (e.g.. Bray et al., 1992). Control on the paleogeothermal gradient allows interpretation of the cause of the heating and subsequent cooling to present temperatures.

In this North Slope foreland basin study, the combination of Ro and AFTT data have helped establish: 1) that maximum paleotemperatures were attained prior to cooling which began in the Paleocene at ~60+/-4 Ma, 2) that paleogeothermal gradients when cooling began were close to the present-day values, and 3) that Cenozoic surfical cooling resulted in a significant amount of "apparent" denudation. This suggests that heating throughout the basin was largely due to deeper burial, and that cooling was due to both removal of section by denudation and by a drop in the mean annual surface temperature of ~10-20deg.C, the effects of which have gone unnoticed across the foreland basin. It is obvious from the values in Figure 1 that denudation is the dominant cause for cooling within the basin, however, it is important to note that the entire North Slope foreland basin has also experienced ~0.5 km of "apparent" denudation. This suggests that estimates of denudation, which did not consider middle to late Cenozoic climatic cooling, or the surface temperature at the time when cooling from maximum paleotemperatures began, may be over-estimated by ~0.5 km.

Finally, the data and interpretations from the North Slope foreland basin illustrate the importance of understanding several factors when evaluating the thermal history and the amount of denudation. These factors include: 1) knowing the mean annual surface temperature at the time maximum paleotemperatures were reached, 2) knowing the geothermal gradient at the time maximum paleotemperatures were reached, and 3) knowing the time at which cooling from maximum paleotemperatures occurred. This study also illustrates how important it is to recognize the affect long-term changes in mean annual surface temperatures have on subsurface cooling and must be considered when estimating denudation.

REFERENCES CITED

Bray, R.J., Green, P.F., and Duddy, I.R. 1992. Thermal history reconstruction using apatite fission track analysis and vitrinite reflectance: A case study from the East Midlands of England and the southern North Sea. In Exploration Britain: Geological Insights For the Next Decade. Edited by R.S.P. Hardman. Geological Society Of London Special Publication 67: 3-25.

Clark, D.L. 1990. Arctic Ocean ice cover; geologic history and climatic significance. In The Arctic Ocean Region. Edited by A. Grantz, L. Johnson, and J.F. Sweeney. Geological Society of America, The Geology of North America, L: 53-62.

 

Howell, D.G., Bird, K.J., Huafu, L., and Johnsson, M.J. 1992. Tectonics and petroleum potential of the Brooks Range fold and thrust belt - a progress report. In Geologic studies in Alaska by the U.S. Geological Survey during 1990. Edited by D.C. Bradley and A.B. Ford. U.S. Geological Survey Bulletin 1999: 112-126.

O'Sullivan, P.B. 1996. Late Mesozoic and Cenozoic thermal evolution of the North Slope foreland basin, Alaska. In Thermal evolution of sedimentary basins in Alaska. Edited by M.J. Johnsson, and D.G. Howell. U.S. Geological Survey Bulletin.

O'Sullivan, P.B., and Brown, R.W., 1996, Fission track evidence for Miocene cooling on the North Slope of Alaska: missing section or crustal cooling [abs.]. International Workshop on Fission-Track Dating, Program with Abstracts, p. 83.


Short Tracks: News

Ed Sobel has finished his postdoctoral work with argonist Nick Arnaud at the University of Clermont-Ferrand. He is now at the University of Potsdam setting up a new fission-track lab. Good luck.

Rasoul Sorkhabi will be on leave from Arizona State University, and will be a visiting scientist at the Department of Earth and Planetary Sciences, Graduate School of Science, Hokkaido University, Sapporo 060 Japan; FAX 81-11-736-3290. Rasoul got his Ph.D. from Kyoto University, Japan, in 1991. He will be at Hokkaido University from October 96 to July 97, and will continue his research on fission-track and Ar-Ar thermochronology of the Himalayan orogen.

Chuck Naeser mentioned that he no longer

has any Fish Canyon Apatite available for distribution. He still has Durango apatite from the U. of Texas collection, and Fish Canyon Zircon. He is not planning to do a recollection of the Fish Canyon Tuff for

general distribution and the FT community needs to consider what to do about age standards.

Micheal Steinmann and Dominik Hungenbuhler from ETH Zurich , working on their dissertations on Andean intra-arc basins in Ecuador at Diane Seward's lab, organized a workshop on basin analysis and fission-track dating for local geoscientists at the University of Quito, Ecuador. The workshop was sponsored by the Swiss agency for development and cooperation. A second workshop is planned for June 1997. More info in On Track 14.

Gulio Viola just started a PhD project at ETH Zurich, working with Neil Mancktelow and Diane Seward on the kinematics, age, and amount of displacement of the Periadriatic Fault System, SW of the Tauern Window in the central eastern Alps.

Ann Blythe finished her postdoctoral work at UC Santa Barbara. She is now at USC in Los Angeles where she has set up a new fission-track laboratory.

This news section is far from complete and more or less only includes people I know or that sent me some information of there current whereabouts. Any information is greatly appreciated. If you're moving, please drop me a short line, so I can track you down in the future. Merry Christmas and a Happy New Year full of new tracks to everybody.


AFTINV32: An Inverse Model for Thermal History Determination Using Apatite Fission Track Data

by Dale Issler

Geological Survey of Canada, Calgary, Alberta T2L 2A7, Canada

(dissler@gsc.nrcan.gc.ca)

Introduction

AFTINV32 is an inverse model for determining time-temperature histories from apatite fission track data. Although it shares some common features with other inverse models (Corrigan, 1991; Lutz and Omar, 1991; Gallagher, 1995; Ketcham et al., in prep.), there are some notable differences in how thermal models are set up and evaluated. The purpose of this article is to introduce AFTINV32 and discuss how it differs from some previous models rather than to provide an exhaustive comparison of the advantages and disadvantages of the various modeling techniques.

Basic Model

AFTINV32 has had a rather protracted history of development. The original model, TINV52, was developed by Sean Willett at Dalhousie University during the late 1980's to early 1990's. The model uses a constrained random search algorithm (see Figure 1) to refine the parameter search space. The model proceeds by generating a set of random forward model thermal solutions which are used to calculate apatite fission track age and length parameters for comparison with observed data. Predicted cumulative track length distributions are assessed with respect to observed lengths using the Kolmogorov-Smirnov statistic and a pass/fail criterion is established at the 0.05 significance level. A further requirement is that predicted fission track ages must be within two standard deviations of the measured age. The initial set of random thermal solutions is updated iteratively, with better-fitting solutions progressively replacing the poorest-fitting members of the set. The model converges when all members of the retained solution set pass the statistical test.

The model has been described and used in a number of studies (e.g. Issler et al., 1990; Willett and Issler, 1992; Ravenhurst et al., 1994) and a more comprehensive account can be found in a manuscript by Willett (to be published in the American Journal of Science).

Modified Version

TINV52 has been modified extensively to become an interactive, user-friendly software package designed to run under the Windows 95 operating system (I know that this is contrary to the Macintosh Universe inhabited by a large segment of fission trackers). The modified inverse model, AFTINV32, differs from TINV52 in how random thermal histories are generated, how the fission track annealing calculations are performed (Issler, 1996), and how temperature and rate constraints are dealt with (see Issler, in press, for further details). The model consists of four 32-bit windowed FORTRAN executable programs: TSORT32 (sorts track length data); PREAFT32 (interactive model initialization); AFTINV32 (inverse model); and POSTFT32 (preparing model output and plots). The software has been designed to allow for easy incorporation of geological constraints into the initial specification of time-temperature and rate bounds. Examples of temperature constraints may include the present temperature and limits on temperatures at the time of deposition or during the development.

Rate constraints can include limits on the direction and/or magnitude of temperature change. A new feature allows users to specify the number of randomly generated heating or cooling events which, for example, allows for investigation of the time range over which a maximum heating event may have occurred.

Differences With Respect to Other Models

An attractive feature of this model is the ease with which geological constraints can be incorporated when specifying the initial parameter search space. The model offers considerable flexibility in specifying temperature and rate bounds and different conditions can be applied to different segments of the thermal history. Unlike some of the other inverse models, rate constraints can be decoupled explicitly from temperature constraints. First, users must specify a time grid with corresponding upper and lower temperature limits for each point. Then maximum heating and/or

Temperature Geologic Time (Ma), Frequency Length Graphs

Figure 1: Illustration of constrained random search inversion method using synthetic apatite fission-track data generated from the true temperature solution (heavy black line on temperature time plots) for random cooling only thermal histories. In the upper left panel, an initial random set of 50 solutions is created (light gray lines in shaded regions). During continued iteration, successive members of the initial set are replaced by improved solutions (middle left panel) until all members of the set are statistically valid (convergence at significance level probability of 5%) (lower left panel). The preferred thermal solution (dashes) is represented as an exponential mean of the solutions contained with the acceptable solution ( heavy black curve in right panels) is shown in comparison with the synthetically generated distribution (histogram). The shaded regions of the length distribution plots indicate the range of the track distributions produced by the random temperature set.

(editor's note: wonder if these figures would look better drawn on a Macintosh...)

cooling rates can be calculated either directly using the time-temperature limits or users can customize their choices for the maximum allowable rates. For example, there may be little control on the acceptable temperature range (and thus a wide range on temperature) for a particular thermal history but users may be able to restrict the magnitude and/or direction of temperature change using other criteria. This approach differs from some other methods (e.g. Lutz and Omar, 1991; Gallagher, 1995) where constraints are defined in terms of the minimum number of points required to fit the data (Occam's Razor) and where time-temperature ranges are supplied for individual points. In this formulation, rates are restricted by and depend on the minimum number of points used. Therefore, the range on acceptable parameter space should be narrower than in models where this restriction is not applied. Although use of the minimum number of points is a valid and useful modeling technique, AFTINV32 provides an alternative, complementary approach.

In addition to limiting the magnitude and direction of temperature change, users can have the model search for heating or cooling events over specified time ranges if there are good geological reasons for doing this. An example might be a foreland basin dominated by an early subsidence phase and late exhumation phase. The timing of maximum temperature may not be well known and the model can be used to generate a series of random thermal histories with a single stage of heating and cooling. These models could provide a range for the time of maximum heating. The usefulness of this approach would depend on how close the sample was to temperatures at which total annealing occurs. This example is similar to the pulse heating type of history used by Corrigan (1991) but thermal histories need not be smooth as required by the Chebyshev polynomial approximation of thermal histories in Corrigan's model. Care should be taken when choosing this option. The model can always find a reheating event when instructed to do so but this "event" may not be required by the data, due to the nonuniqueness problem.

AFTINV32 uses the empirical isothermal annealing equation of Crowley et al. (1991) with coefficients for Sr fluorapatite, fluorapatite and Durango apatite (Crowley et al., 1991) and for the Durango model of Laslett et al. (1987). This equation is solved efficiently and accurately using an equation which predicts the integration step size as a function of rate of temperature change and maximum interval temperature for each linear heating segment of a given thermal history (Issler, 1996). This avoids having to choose a uniformly small step size for the entire model history in order to maintain sufficient accuracy at high temperatures and high rates of temperature change. Coefficients for the time step predictor equation have been optimized for each of the compositionally-dependent annealing models.

All of the inverse models use an iterative direct search scheme for locating statistically-acceptable thermal solutions. Ketcham et al. (in prep.) employ random Monte Carlo simulation in which a large number of independent, random thermal histories are generated. Solutions that fit the data are used to define the parameter space. AFTINV32 also uses random Monte Carlo simulation but the approach is closer to that of Gallagher (1995). The constrained random search algorithm is very similar to the genetic algorithm used by Gallagher (1995) in that the model uses information from the initial random selection to improve the fit of subsequent models. However, unlike the model of Gallagher (1995), AFTINV32 does not try to find the optimum solution. This is in recognition of the fact that the apatite fission track data are not optimal but are an imperfect sample of the "true" population of tracks. Instead, a pass/fail criteria is used to build up a family of acceptable solutions and a weighted average is chosen as being representative of the thermal history.

How to Obtain the Model

The computer software and an accompanying user's manual are being published as a Geological Survey of Canada Open File that will be available from our Calgary bookstore (same address as above) in either November or December 1996 (Issler, in press). I am told that the price should be approximately $50 (Canadian funds - so far we are not a profit-driven organization but pressures are mounting). For those interested in obtaining the software and document, further information can be obtained by contacting the Calgary bookstore at: (403) 292-7030 (phone); (403) 299-3542 (Fax); gsc_calgary@gsc.NRCan.gc.ca (Internet). I plan on making future modifications to the program to keep on top of advances in fission track research and if bugs in the program are discovered, I'll fix them. The current model uses the empirical annealing equation of Crowley et al. (1991) with coefficients for 4 different apatite compositions and options for inserting other coefficients. Other annealing models will be incorporated in future versions.

References

Corrigan, J.D. 1991. Inversion of apatite fission track data for thermal history information. Journal of Geophysical Research, v. 96, no. B6, p. 10347-10360.

Crowley, K.D., Cameron, M. And Schaefer, R.L. 1991. Experimental studies of annealing of etched fission tracks in fluorapatite. Geochimica et Cosmochimica Acta, v. 55, no. 5, p. 1449-1465.

Gallagher, K. 1995. Evolving temperature histories from apatite fission-track data. Earth and Planetary Science Letters, v. 136, p. 421-435.

Issler, D.R. 1996. Optimizing time step size for apatite fission track annealing models. Computers & Geosciences, v. 22, no. 1, p. 67-74.

Issler, D.R. in press. An inverse model for extracting thermal histories from apatite fission track data: instructions and software for the Windows 95 environment. Geological Survey of Canada, Open File Report 2325, 84p. (Nov. or Dec. 1996)

Issler, D.R., Beaumont, C., Willett, S.D., Donelick, R.A., Mooers, J. and Grist, A. 1990. Preliminary evidence from apatite fission track data concerning the thermal history of the Peace River Arch region, Western Canada Sedimentary Basin. Bulletin of Canadian Petroleum Geology, v. 38A, p. 250-269.

Ketcham, R.A., Donelick, R.A. and Carlson, W.D. in prep. Numerical modeling of fission track annealing in apatite. In: Naeser, C.W., Dokka, R.K. and Naeser, N.D. (eds.), Fission-Track Thermochronology - Geological Applications.

Laslett, G.M., Green, P.F., Duddy, I.R. and Gleadow, A.J.W. 1987. Thermal annealing of fission tracks in apatite 2. A quantitative analysis. Chemical Geology (Isotope Geoscience Section), v. 65, no. 1, p. 1-13.

Lutz, T.M. and Omar, G. 1991. An inverse method of modeling thermal histories from apatite fission-track data. Earth and Planetary Science Letters, v. 104, no. 2/4, p. 181-195.

Ravenhurst, C.E., Willett, S.D., Donelick, R.A. and Beaumont, C. 1994. Apatite fission track thermochronometry from central Alberta: implications for the thermal history of the Western Canada Sedimentary Basin. Journal of Geophysical Research, v. 99, p. 20023-20041.

Willett, S.D. and Issler, D.R. 1992. Apatite fission track thermochronometry applied to the Western Canada Sedimentary Basin. In: Zentilli, M. and Reynolds, H. (eds.), Short Course Handbook on Low Temperature Thermochronology, v. 20, Mineralogical Association of Canada (Wolfville, Nova Scotia), p. 157-183.


Modeling Annealing With Mathematica

by David A. Coyle

Max Plank Institut - Kernphysik, D-6900 Heidelberg, Germany

(dcoyle@goanna.mpi-hd.mpg.de)

(editor's note: This is an abbreviated version of Dave's article. The complete version can be found on the web, where you can also see MathAnneal in action.)

Introduction

After the amazing displays of technical wizardry at Gent, I promised Danny that I would show how one can make those cool movies using Mathematica. Well, the fact that this article is not about making movies should not be taken as meaning that it's not possible: it's just that the output from freely-available Mathematica contouring routines was less than impressive, and I was really not interested in hacking the C code to make it pretty (and let's face it: the whole point to the exercise was to have something pretty). But those contouring routines ran using a little-used capability of Mathematica called MathLink, and that got me thinking...

An unimpressive contour plot of randomly-spaced data points to get a movie, you just generate a series of these, select them, and press command-y. That's not so hard, is it? Coloring them in can be done using Adobe Illustrator, for example.

If you know me at all, you know that I've been doing my track work with Mathematica for about six years now. So you may have wondered why I have never implemented the Laslett et al annealing algorithms in Mathematica (OK, so you didn't wonder. Just indulge my ego a little, would you?). The reason is simple: Mathematica is interpreted, and the annealing algorithms like to repeatedly iterate through (potentially) large arrays of numbers. Fine, Mathematica would do it, no problem. But it'd be a dog in terms of performance. So I left that problem, and later wrote it up in Objective-C.

So, I have working C-code for annealing, and I have Mathematica. How can I use them together? The answer is MathLink: it lets you access compiled routines from within Mathematica, and also access Mathematica functions from your own programs. Want to do a numerical integration, but are just too lazy to copy all that code out of Numerical Recipes? No problem, MathLink will do it for you. MathLink lets you use Mathematica's fancy plotting capabilities from within your own applications (see, e.g.., UHMath and the UHMathView from the University of Houston). But for us, MathLink lets us use faster compiled annealing routines from within Mathematica's flexible and interactive notebook interface. So, how do you do it?

MathLink makes interprocess communication magical (which is to say, it takes all the fun out of it). If you're going to access your C-code from within Mathematica, all you need to do is provide a template for each function that you'll be calling, and add a single line to your main() function that gets MathLink up and running (see Listing 1). Then process the code with a little program called mprep, compile, link and enjoy. If you've already got the code from another project, ML-ifying it is a trivial task. This project took me about an hour of actual work (coffee breaks not included), and this was the very first time I'd ever used MathLink. In fact, I've spent more time writing this article, than I did writing the MathLink program!

Listing 1: A MathLink Objective-C source file with Template

#import <WebObjects/WebObjects.h>

#import "Annealer.h"

#import "mathlink.h"

:Begin:

:Function: annealTracks

:Pattern: Annealtracks[points_List]

:Arguments: { points }

:ArgumentTypes: { RealList }

:ReturnType: Manual

:End:

int main (int argc, char* argv[])

{return MLMain(argc, argv);}

void annealTracks(double *points, int alen) {

/*" alen is the length of the list "*/

Annealer *myAnnealer = [[Annealer alloc] init];

// rest omitted

...

Once your program compiles without errors or warnings, then you can test it from Mathematica. Accessing the functions is easy: you just use Mathematica's Install[] directive, thus:

myLink = Install["/LocalScientist/bin/MathAnneal"];

This returns a Link object, which in this example is assigned to the variable myLink.

So what's the point?

Well, the point is that people are reasonably sure of the validity of the annealing model they use (until PFG releases the multi-compositional model, that is...) and so it's quite natural to make that an immutable compiled function. Methods of generating and evaluating thermal histories, on the other hand, vary greatly. There's genetic algorithms, Monte Carlo, Simulated Annealing (yes, I know it's confusing), the promising "Great Deluge" algorithm, just to name a few. And that's not to mention the fact that just comparing your observed to modeled data is riddled with uncertainties. Geoff Laslett once told me that there are no robust ways of comparing histograms (well, something along those lines..."binned data" I think he said). That says it all, eh?

In Mathematica, writing functions to do customized path generation is really simple (see example). The same is true for comparing observed to modeled data. In practice, what you'd probably do is write new generate-anneal-refine routines for each new sample, sample suite, or sample category (good, bad, indifferent), adapting previous routines to the unique problems and geological environments of your projects. You'll never have an excuse for that uncomfortable feeling that you get when you use present-day programs ("Just what do these MonteTrax parameters really mean?"). Plus there are all kinds of packages available from Wolfram research itself, to help you do just these things. Browse around in http://www.mathsource.com/

Here's an example of simple function to create a monotonically-cooling history, with random point selection, and an arbitrary number of segments.

Note, this is the verbose version...

Clear[BuildPaths];

BuildPaths[maxt_Real, presT_Real, startT_Real,

num_Integer, segs_Integer] :=

Module[{a, t, bl, op},

op = {};

bl = {};

Do[ bl = {{maxt, Random[Real, startT]}, {0.0, presT}};

(* This example actually sets the starting temp as *)

(* some random number between zero and startT *)

If[segs > 1,

(*We need to build up bl by inserting nodes*)

a = Sort[Table[Random[Real, maxt], {segs-1}], Greater]; (* times *)

t = Sort[Table[Random[Real, 140.0], {segs-1}], Greater]; (* temps *)

bl = Partition[Flatten[Insert[bl, Transpose[{a,t}], -2]], 2];

];

AppendTo[op, bl]

, {num} ];

op ]

But the main point for me, is that now I've finally got all my data generation and evaluation software together in one place. I determine my ages and plot my radial plots using my FTD package, I do 2-component analyses using my 2CM package. I fool around with "minimum" ages using my Minimage package. And I read in and process my confined length data using my LengthHandler package (which at present only deals with TrevorScan files, but that can be changed. Call for a quote.). And the cool thing about it all, is that it doesn't require any particular operating system. Mac, Windoze, UNIX, VMS: Mathematica doesn't care (though I certainly do...) .

Not quite true: your Annealer MathLink program won't run everywhere! Well, sorry to disappoint you there, but it can. The MathAnneal program uses the Gnu Objective-C++ compiler (gcc), which runs just about anywhere (except the Mac, but that'll change when Linux runs on the PowerMac). If you don't have Next/OpenStep (from Sun [comes with NEO], or NeXT itself), you can install the Free Software Foundation's GnuStep, which implements every one of the (very few!) Common and Foundation classes that I've used in creating MathAnneal. So if you're running W95, WinNT, DEC OSF/1, Solaris, Linux, or some others I've forgotten, then probably you can also use my sources, with only a minimum of changes (the makefile, #import directives, and so on...). By the time you read this, I'll probably have it running on WindosNT, since NeXT is kindly giving me a copy of OpenStep/NT for free.

Mathematica itself is ubiquitous in academic departments: I'd be really surprised if you don't already have a license for your uni/department/lab.

Summary

So, in total, the MathLink solution to modelling fission-track data is quite attractive. You get custom search algorithms, a nearly-interactive interface (check out the Mathematica function that lets you click or drag in a Graphic view, and convert the point(s) into a List of {x, y} coordinates), full source code for your inspection, robust methods, and a clean Annealer engine that is reasonably efficient. Another point I didn't mention is that the annealing engine can be easily swapped for another, if/when better algorithms are made publicly available (PFG, are you listening?). It's also a handy way to compare annealing algorithms, or to debug that little module of code that you may want to build into a larger program (well, why would you, now).

I have to admit that at first even I was skeptical (doing this only as an alternative to the movie project), but now I've even sold myself on it. I think that I'll be doing a lot more modelling this way, from now on. I hope you will too.

Here is an example of the modeling results generated using Mathematica (ed.):

Modeling results generated using Mathematica (ed.)

Epilogue

Well, I hope you've enjoyed this extremely brief introduction into the possibilities offered by Mathematica and MathLink. My wish is that, rather than expecting others to do it all for you, you'll now be motivated into finding your own, individual, solutions to your unique modeling problems.


A Better Way to Separate Apatite from Zircon Using Constriction Tubes

by Trevor Dumitru and Danny Stockli

Department of Geological and Environmental Sciences, Stanford University,

Stanford, California 94305-2115 USA

(trevor@pangea.stanford.edu)

Most FT laboratories currently separate apatite from zircon in separatory funnels using methylene iodide (MEI, density 3.32). We have found it better to undertake these separations using constriction tubes inserted inside glass test tubes. We simulated this in Gent using water, successfully separating plastic bits from quartz grains in about 15 seconds. Everyone, I'm sure, was duly impressed.

We have a profusely illustrated write-up available with all the details that we handed out in Gent. Anyone who didn't get one can write or email for a copy. A Microsoft Word for Macintosh version is available via email, so please specify if you can handle attached Macintosh email files.

To summarize the procedure, we usually work with batches of about twenty samples following this general procedure:

1--Fill twenty standard 16 mm diameter test tubes with ~4 ml of MEI from a buret.

2--Insert glass constriction tubes into each test tube. Our local glassblowing shop makes these for us for US$4 each.

3--Pour the nonmagnetic apatite + zircon splits into the centers of the constriction tubes. Cap the test tubes.

4--Tap, jiggle, and knock the tubes to stir the grains a bit. Repeat several times with short breaks in between to allow settling. The key point is that if you agitate very gently the first time, then progressively more vigorously, virtually all zircon adhering to the tube walls will be washed free and sink. Unlike separatory funnels, there is no need to use a stirring rod or rinse down the walls with MEI from those retched little squeeze bottles.

5--Anchor the test tubes one at a time in a ringstand test tube clamp that will rotate, remove the cap, then insert a rod or needle to block the constriction. We have found that Teflon coated knitting needles work well.

6--Use forceps to carefully lift out the constriction tube and the MEI and apatite it contains. Drain the constriction tube into filter paper to recover the apatite, catching the MEI in a flask. Shift the filter funnel to a wash flask and rinse with acetone from a squeeze bottle.

Glass constriction tube, 16 mm diameter test tube, Knitting needle, Apatite after separation, ME 1 level, Block constriction before lifting out constriction tube, Zircon afgter

7--Tip the test tube into a second filter paper to recover the remaining MEI and the zircon. We do this by smoothly rotating the test tube clamp until the test tube is tipped 10deg. past horizontal. After the tube has drained of MEI, we used a special acetone squeeze bottle with its tip bent 10deg. upward to squirt acetone up into the bottom of the tube and wash out the remaining MEI and zircon into the filter (over a wash flask).

This procedure is about twice as fast as using separatory funnels and uses so little MEI per sample that MEI loss into wash is reduced to roughly 0.5 ml per sample. However the equipment should be selected with care. Key pitfalls include: (1) the constriction tube must fit loosely within the test tube to avoid squirting MEI when the constriction tube is inserted or removed; (2) a rotatable test tube clamp is essential to hold the test tube while it is being tipped to drain the MEI and zircon; (3) the height and tip angle of the acetone squeeze bottle must be matched to the test tube clamp height and angle so that you can cleanly squirt acetone up into the bottom of the test tube to rinse out the MEI and zircon; (4) the sample must be smaller than about 0.1 cm3 (250 mg) to get a very clean separation. We split larger samples in multiple tubes.

Disclaimer: MEI and acetone are hazardous; consult other sources for proper safety precautions. Practice this procedure with water before undertaking it with MEI. You really should read our detailed handout before attempting this procedure. Use at your own risk.

 

On Track Technical News

New improved grinding plates from Bico

Trevor Dumitru

Department of Geological and Environmental Sciences,

Stanford University, Stanford, California 94305-2115, U.S.A.

About a year ago we were having problems getting a good grind out of our Bico disc grinder ("Bico Pulverizer Type UA"), so we decided to investigate and see what could be done to improve the situation. The grinding plates were wearing out fast, they tended to jam with rock fragments that would not grind down, and the output of the grinder had a wider range of grain sizes than we wanted.

We came up with two significant improvements. First, the plates on our Bico jaw crusher ("Braun Chipmunk") proved on inspection to be worn down by a few millimeters. We replaced them and it helped a lot, producing a much finer crush to then feed into the grinder. I had looked at the crusher plates before and didn't think the wear would make any difference, but it did. We generally crush each sample twice, one pass with the plates at maximum separation followed by one at minimum separation. This has made our grinder much happier.

Second, we called Bico and found they had a new type of grinding plate for their disc grinder, the "Lead Dog" plate. We tried some of these and they are a genuine improvement, lasting roughly three times as long. For our model grinder the plates are part numbers LD-03 (Stationary Semi Steel Plate, 8 inch diameter) and LD-04 (Revolving Semi Steel Plate, 8 inch diameter). A set is about $60 in the U.S.

Bico Inc.

3116 Valhalla Drive

Burbank California 91505 USA

Phone 1-818-842-7170

Fax 1-818-842-7976


 

Group order of PFA Teflon planned

Trevor Dumitru and Danny Stockli

Department of Geological and Environmental Sciences,

Stanford University, Stanford, California 94305-2115, U.S.A.

(trevor@pangea.stanford.edu; fax 1-415-725-6155)

Several fission track labs, including Kyoto Fission Track Company, Kyoto University, and ETH-Zurich, have been using PFA Teflon for mounting zircons and have found it superior to the older FEP Teflon. Dupont, the maker, advertises that PFA is suitable for applications at temperatures higher than 250deg.C. Danhara et al. discussed the merits and mounting procedures for PFA in the November 92 issue of On Track, finding it was eroded considerably less by the zircon etchant. This and the higher melting temperature reduce the numbers of zircons that fall out during etching.

However, it has been hard for individual labs to buy PFA because suppliers generally have minimum order sizes of about 5 or 10 square meters (enough for 20,000 to 40,000 zircon mounts) at a cost of about $1000. We are therefore trying to assemble a group order from several labs.

We are going to order PFA Teflon sheet, 12 inches wide, 0.5080 mm thick. The approximate price including shipping to the individual labs will be $150 per square meter. The minimum order we need to assemble is 8.36 square meters, or about $1250 (including estimated shipping costs to the individual labs). The supplier is also willing to fill smaller orders, but will add a $200 service charge to the cost in that case.

If your lab would like to participate, please send the order form below to me by 31 December 1996. The key terms are as follows:

1--Individual labs that sign up by 31 December 1996 will receive their Teflon at dealer's cost plus their share of the shipping fees. For simplicity, shipping fees will be split equally, thus U.S. labs will subsidize shipping to other labs by a small amount.

2--Payment must be made by check or electronic payment in U.S. dollars drawn on a U.S. bank, check payable to Trevor Dumitru rather than Stanford University. Shipment will be made to the individual labs via U.S. Postal Service air mail. Usual customs duties and delays may apply outside the U.S. I am happy to write receipts, etc., but hope that buyers will help minimize the amount of paperwork that I need to do. If any lab cancels out or fails to pay, it will come out of my pocket, and I will pillar you in the next issue of On Track.

3--We cannot guarantee the Teflon will work in your lab. Sorry, no refunds.

4--Please consider ordering all you want now. We do not expect to repeat the order in the foreseeable future. Estimated delivery date is March 1997.


PFA Teflon Order Form

Name, lab, and mailing address of buyer:

Phone, fax, and email addresses:

Amount you wish to buy, in square meters, minimum order is 0.5 square meters:

Cost of your order at $150 per square meter. Please note that you may be charged up to

10% more, but will probably actually be charged slightly less, depending on final cost.:

If we do not receive enough interest to total $1250, we will need each lab to contribute equally toward the $200 service fee for small orders. Please check the maximum amount you are willing to pay extra toward your share of this $200 fee if it proves necessary. If your contribution is smaller than needed, your order will be canceled. If it is larger than needed, you will pay only the amount needed.:

___$100 (2 labs participating) ___$50 (4 labs participating) ___$25 (8 labs participating)

___$67 (3 labs participating) ___$40 (5 labs participating) ___$20 (10 labs participating)

This is a firm agreement to participate in this group order. You agree to pay the amounts due in a timely manner. Do not pay now, but payment in advance may be needed (we will contact you).

Mail, fax or email to: Dumitru, Dept. of Geol. & Env. Sciences, Stanford Univ., Stanford California 94305-2115 USA; Fax 1-415-725-6155; email trevor@pangea.stanford.edu. Deadline December 31, 1996

(information may be sent by email without the form)


Recent Fission-Track Papers

Please send items for future listings in On Track to the editor, Danny Stockli. The reference or a photo copy of the first page will suffice but a copy of the entire paper is appreciated. We especially want non-fission-track papers that may be of special interest to the fission-track community. Papers in press are welcome, please include an estimate of the expected month of publication.

Balestrieri, M. L.; Abbate, E.; Bigazzi, G. (1996) Insights on the thermal evolution of the Ligurian Apennines (Italy) through fission-track analysis. Journal of the Geological Society of London ; Vol. 153, Part 3, p. 419-425

Blythe, Ann E.; Bird, John M.; Omar, Gomaa I. (1996) Deformation history of the central Brooks Range, Alaska; results from fission-track and 40Ar/39Ar analyses. Tectonics ; Vol. 15, No. 2, p. 440-455

Carter, Andrew; Bristow, Charles; Hurford, Anthony (1995) Constraints on the thermal history and provenance of the Khorat Group in Thailand using fission track analysis.

Journal of Geology, Series B ; Vol. 1995, No. 5-6, p. 341-353

Carter, A.; Yelland, A.; Bristow, C.; Hurford, A. J. (1995) Thermal histories of Permian and Triassic basins in Britain derived from fission track analysis. Geological Society Special Publications ; Vol. 91, p. 41-56

Chen, Y.; Zentilli, M. A.; Clark, A. H.; Farrar, E.; Grist, A. M.; Willis-Richards, J. (1996) Geochronological evidence for post-Variscan cooling and uplift of the Carnmenellis Granite, SW England. Journal of the Geological Society of London ; Vol. 153, Part 2, p. 191-195

Coyle, David A; Wagner, Guenther A. (1995) Fission tracks; a report on post-Variscan tectonics and compensation in the KTB region. Die Geowissenschaften (Weinheim, Zeitschrift) ; Vol. 13, No. 4, p. 142-146

Crowhurst, P. V.; Hill, K. C.; Foster, D. A.; Bennett, A. P. (1996) Thermochronological and geochemical constraints on the tectonic evolution of northern Papua New Guinea. J. Geological Society Special Publications; Vol. 106, p. 525-537

Currie, Lisel D.; Grist, A. M.; O'Sullivan, P. B. (1996) New apatite fission track results from Vancouver Island, the southern Coast Mountains, and the St. Elias Mountains; implications and questions for the Tertiary and younger tectonic history of the western Canadian Cordillera. Lithoprobe Report ; Vol. 50, p. 163

DeWolf, C. P.; Zeissler, C. J.; Halliday, A.N.; Mezger, K.; Essene, E. J. (1996) The role of inclusions in U-Pb and Sm-Nd garnet geochronology; stepwise dissolution experiments and trace uranium mapping by fission track analysis. Geochimica et Cosmochimica Acta ; Vol. 60, No. 1, p. 121-134

Fitzgerald, P.G., and Baldwin, S.L., (in press) Detachment fault model for Cretaceous extension in the Ross Embayment, Antarctica: Geologic and fission track constraints from DSDP site 270: Terra Antarctica.

Fitzgerald, P.G., and Stump, E., (in press) Cretaceous and Cenozoic episodic denudation of the Transantarctic Mountains, Antarctica: New constraints from apatite fission track thermochronology in the Scott

Glacier region: Journal of Geophysical Research.

(this contains a heap of FT data! - PGF)

Foster, David A.; Gleadow, Andrew J. W. (1996) Structural framework and denudation history of the flanks of the Kenya and Anza rifts, East Africa

Tectonics ; Vol. 15, No. 2, p. 258-271

Howard, Keith A.; Foster, David A. (1996) Thermal and unroofing history of a thick, tilted Basin-and-Range crustal section in the Tortilla Mountains, Arizona. Journal of Geophysical Research, B, Solid Earth and Planets ; Vol. 101, No. 1, p. 511-522

Issler, Dale R. (1996) Optimizing time step size for apatite fission track annealing models. Computers & Geosciences ; Vol. 22, No. 1, p. 67-74

Keeley, M. L. (1995) New evidence of Permo-Triassic rifting, onshore southern Ireland, and its implications for Variscan structural inheritance. Geological Society Special Publications ; Vol. 91, p. 239-253

Lovatt Smith, Paul F.; Stokes, Robert B.; Bristow, Charlie; Carter, Andrew (1996) Mid-Cretaceous inversion in the northern Khorat Plateau of Lao PDR and Thailand Geological Society Special Publications ; Vol. 106, p. 233-247

McDonough, Michael R.; Issler, Dale R.; Stockmal, Glen S.; Grist, Sandy; Zentilli, Marcos; Archibald, Douglas A.; Scammell, Robert J. (1996) Contrasting cooling histories from apatite fission track and 40Ar-39Ar analysis of the internal and external zones of the Canadian Rockies near Jasper, Alberta and Valemount, British Columbia. Lithoprobe Report ; Vol. 50, p. 206

Morillon, A. C.; Bourgois, J.; Poupeau, G.; Sosson, M. (1996) Lower Miocene uplift of the Los Reales and Ojen nappes (Internal Betic Zone, Spain) from apatite fission track analysis. Comptes Rendus de l'Academie des Sciences, Serie II. Sciences de la Terre et des Planetes ; Vol. 322, No. 10, p. 885-891

Osadetz, Kirk G.; Kohn, Barry P.; Feinstein, Shimon; Price, Raymond A. (1996) Apatite fission-track data from below the Lewis thrust fault and its implications for the thermal history of the Cordilleran foreland belt and the age of the Flathead normal fault

Lithoprobe Report ; Vol. 50, p. 151-152

O'Sullivan, P.B. and Parrish, R.R. (1995) The importance of apatite composition and single-grain ages when interpreting fission track data from plutonic rocks: A case study from the Coast Ranges, British Columbia: Earth and Planetary Science Letters, v. 132, p. 213-224.

O'Sullivan, Paul B.; Foster, David A.; Kohn, Barry P.; Gleadow, Andrew J. W. (1996) Multiple postorogenic denudation events; an example from the eastern Lachlan fold belt, Australia. Geology; Vol. 24, No. 6, p. 563-566

O'Sullivan, P.B., Foster, D.A., Kohn, B.P., Gleadow, A.J.W., and Raza, A. (1995) Constraints on the dynamics of rifting and denudation on the eastern margin of Australia: Fission track evidence for two discrete causes of rock cooling, in Mauk, J.L. and St. George, J.D., eds., Pacific Congress 1995: Proceedings of the 1995 PACRIM Congress, p. 441-446.

O'Sullivan, P.B., Kohn, B.P., Foster, D.A., and Gleadow, A.J.W., 1995) fission track data from the Bathurst Batholith: evidence for rapid middle

Cretaceous uplift and erosion within the eastern highlands of Australia: Australian Journal of Earth Sciences, v. 42, p. 597-607.

O'Sullivan, P.B., Hanks, C.L., Wallace, W.K. and Green, P.F. (1995) Multiple episodes of Cenozoic denudation in the northeastern Brooks Range: fission track data from the Okpilak batholith, Alaska: Canadian Journal of Earth Sciences, v. 32, p. 1106-1118.

O'Sullivan, P.B. (1996) Late Mesozoic and Cenozoic thermal-tectonic evolution of the North Slope foreland basin, Alaska, in Johnsson, M.J. and Howell, D.G., eds., Thermal Evolution Of Sedimentary Basins In Alaska: U.S. Geological Survey Bulletin 2142, p. 45-79.

O'Sullivan, P.B., and Currie, L.D. (1996) Tectonic implications of multiple episodes of Middle to Late Cenozoic denudation of Mt Logan, Yukon Territory, Canada: Earth and Planetary Science Letters, v. 144, p. 251-262.

O'Sullivan, P.B., Foster, D.A., Kohn, B.P. and Gleadow, A.J.W. (1996) Tectonic implications of Early Triassic, and middle Cretaceous denudation in the eastern Lachlan Fold Belt, NSW, Australia: Geology, v. 24, n. 6, p. 563-566

Pivnik, David A.; Khan, M. Javed (1996) Transition from foreland- to piggyback-basin deposition, Plio-Pleistocene upper Siwalik Group, Shinghar Range, NW Pakistan. Sedimentology ; Vol. 43, No. 4, p. 631-646

Ren Zhanli (1995) Thermal history of Ordos Basin assessed by apatite fission-track analysis. Acta Geophysica Sinica ; Vol. 38, No. 3, p. 339-349

Roy, P. S.; Matthei, L. (1996) Late Cainozoic clay deposits in the Port Stephens area, New South Wales. Australian Journal of Earth Sciences ; Vol. 43, No. 4, p. 395-400

Saddiqi, O.; Poupeau, G.; Michard, A.; Goffe, B.; Oberhaensli, R. (1995) Exhumation of HP-BT Oman metamorphic rocks; fission track dating on zircons. Comptes Rendus de l'Academie des Sciences, Serie II. Sciences de la Terre et des Planetes ; Vol. 320, No. 11, p. 1071-1077

Shane, Philip A. R.; Black, Tasha M.; Alloway, Brent V.; Westgate, John A. (1996) Early to middle Pleistocene tephrochronology of North Island, New Zealand; implications for volcanism, tectonism, and paleoenvironments. Geological Society of America Bulletin ; Vol. 108, No. 8, p. 915-925

Shi Yaolin; Allis, Rick; Davey, Fred (1996) Thermal modeling of the Southern Alps, New Zealand. Pure and Applied Geophysics ; Vol. 146, No. 3-4, p. 469-501

Sorkhabi, R.B., Stump, E., Foland, K.A., and Jain, A.K., (1996). Fission-track and 40Ar/39Ar evidence for episodic denudation of the Gangotri granites in the Garhwal Himalaya, India. Tectonophysics (in press)

Sorkhabi, R.B., Stump, E., Foland, K.A., and Jain, A.K., (1997). Tectonic and cooling history of the Garhwal Higher Himalaya (Bhagirathi Valley): Constraints from thermochronological data; Memoir of Geology Society of India 39 (in press).

Sorkhabi, R.B. (1996) Book review of "Fission Track Dating" by G. Wagner and P. van den Haute. Radiation Measurements, v. 26, pp. 144-145.

Storey, B. C.; Brown, R. W.; Carter, A.; Doubleday, P. A.; Hurford, A. J.; MacDonald, D. I. M.; Nell, P. A. R. (1996) Fission-track evidence for the thermotectonic evolution of a Mesozoic-Cenozoic fore-arc, Antarctica. Journal of the Geological Society of London ; Vol. 153, Part 1, p. 65-82

Tagami, Takahiro; Carter, Andrew; Hurford, Anthony J. (1996) Natural long-term annealing of the zircon fission-track system in Vienna Basin deep borehole samples; constraints upon the partial annealing zone and closure temperature. Chemical Geology ; Vol. 130, No. 1-2, p. 147-157

Tagami, Takahiro; Shimada, Chica (1996) Natural long-term annealing of the zircon fission track system around a granitic pluton. Journal of Geophysical Research, B, Solid Earth and Planets ; Vol. 101, No. 4, p. 8245-8255

Tagami, Takahiro; Hasebe, Noriko; Shimada, Chica (1995) Episodic exhumation of accretionary complexes; fission-track thermochronologic evidence from the Shimanto Belt and its vicinities, Southwest Japan. The Island Arc ; Vol. 4, No. 3, p. 209-230

Tseng, Hsin-Yi; Onstott, T. C.; Burruss, R. C.; Miller, D. S. (1996) Constraints on the thermal history of Taylorsville Basin, Virginia, U. S.A., from fluid-inclusion and fission-track analyses; implications for subsurface geomicrobiology experiments

Chemical Geology ; Vol. 127, No. 4, p. 297-311

Upton, David; Bristow, Charlie; Hurford, Anthony J. (1995) The denudational history of western Thailand using apatite fission track analysis; implications for the tectonic models of SE Asia. Journal of Geology, Series B ; Vol. 1995, No. 5-6, p. 322

Van der Beek, P. A.; Delvaux, D.; Andriessen, P.;A. M.; Levi, K. G. (1996) Early Cretaceous denudation related to convergent tectonics in the Baikal region, SE Siberia. Journal of the Geological Society of London ; Vol. 153, Part 4, p. 515-523

Vella, Paul; Vucetich, C. G.; Kohn, Barry P.; Pillans, Brad; Alloway, Brent V. (1996)

Fission track age estimates for Mount Curl Tephra. New Zealand Journal of Geology and Geophysics ; Vol. 39, No. 2, p. 333-335

Winkler, W.; Steinmann, M.; Hungerbuehler, D.; Baudino, R.; Lavenu, A.; Delfaud, J. (1996) A major Neogene tectonic event in the southern Ecuadorian Andes; synsedimentary deformation from Nabon Basin; discussion and reply. . Comptes Rendus de l'Academie des Sciences, Serie II. Sciences de la Terre et des Planetes ; Vol. 322, No. 6, p. 515-521

Yang, Tsanyao F.; Tien, Jung-li; Chen, Cheng-Hong; Lee, Typhoon; Punongbayan, Raymundo S. (1995) Fission-track dating of volcanics in the northern part of the Taiwan-Luzon Arc; eruption ages and evidence for crustal contamination. Journal of Southeast Asian Earth Sciences ; Vol. 11, No. 2, p. 81-93

Zhao, Meng-Wei; Behr, Hans-Juergen; Ahrendt, Hans; Wemmer, Klaus; Ren Zhanli; Zhao Zhongyuan (1996) Thermal and tectonic history of the Ordos Basin, China; evidence from apatite fission track analysis, vitrinite reflectance, and K-Ar dating.

AAPG Bulletin ; Vol. 80, No. 7, p. 1110-1134


Call for Contributions to the

May 1997 On Track issue 14

Dear Fellow Fission Tracker:

The next issue will be printed in May, 1997 and we are looking for contributions. We welcome contributions of virtually any kind, including descriptions of new lab techniques, reviews of useful products, news and gossip, raving editorials about what all the other labs are doing wrong (or right), corrections of errors that appeared in the previous issue, meeting announcements, job openings, cartoons, and descriptions of what you are doing in your research.

On Track always includes a list of Recent Fission-Track Papers. If you know of a paper that was published recently, or that is in press and should be published in the near future, please send it in. The Short Tracks: News section allows all of us to keep up with fission "trekking" around the globe. On Track also includes an International Fission-Track Directory in each November issue, with errata and amendments in the May issue. If you are about to move, have moved, or know of someone who has moved, please inform me so the directory can be updated.

If you would like to contribute, send the final text and figures before the DEADLINE, 15 APRIL, 1997. If it is a lengthy article, let me know the title and length as soon as possible. Please send a paper copy of your contribution and a 3.5 inch Macintosh&tm; compatible disc with the text saved in Microsoft Word. If you can't send a Macintosh compatible disc, send a 3.5 inch IBM compatible disc in Word, or WordPerfect. Contributions can also be sent electronically. Send all contributions for the next issue of On Track to:

 

Danny Stockli, On Track Editor

Department of Geological and Environmental Sciences

Stanford University

Stanford, California 94305-2115, U.S.A.

Tel.: 415-725-6155

Fax: 415-725-6155

E-mail: danny@pangea.stanford.edu


1996

DIRECTORY OF THE INTERNATIONAL

FISSION-TRACK COMMUNITY

This directory is published solely for the information of fission-track researchers. It is neither a comprehensive directory including all fission-track researchers nor an official document endorsing the scientific stand of individuals by the fission-track community. We provide here an update to the initial directory prepared by Rasoul Sorkhabi with the hope that we have accounted for the changes in addresses that have occurred since the last release of the directory. If you have changed your address, know someone else who has or think that someone should be on this list, please let me know (danny@pangea.stanford.edu)!

Andriessen, Paul A.M.

Laboratorium voor Isotopen Geologie,

Faculteit der Aardwetenschappen

Vrije Universiteit

de Boelelaan 1085

1081 HV Amsterdam, The Netherlands

Arne, Dennis C.

Department of Geology

University of Ballarat, P.O. Box 663

Ballarat, Victoria 3352, Australia

Tel.: 61-53-279-290,

Fax: 61-53-279-144

Email: DCA@fs3.ballarat.edu.au

Bal, K.D.

Fission Track Laboratory

Special Research Group

ERD Building, 3RD Floor

KDM Institute of Petroleum Exploration

Oil and Natural Gas Corporation

Dehradun, India

Baldwin, Suzanne

Department of Geosciences

University of Arizona

Tucson, AZ 85721,

United States of America

Balestrieri, Maria Laura

Dipartimento di Scienze della Terra

via S. Maria, 53

56126 Pisa, Italy

Bergman, Steven C.

ARCO Exploration and Production Technology

2300 W. Plano Parkway

Plano, TX 75075-8499,

United States of America

Tel.: 1-214-754-6264,

Fax: 1-214-754-6807

E-mail: dprscb@arco.com

Bigazzi, Giulio, Ph.D.

Instituto di Geochronologia e Geochimica Isotopica,

CNR, via Cardinale Maffi, 36

56127 Pisa, Italy

Tel.: +39-50-560430/560110,

Fax: +39-50-589008

Blythe, Ann E.

Department of Geological Sciences

University of California

Santa Barbara, CA 93106,

United States of America

Tel. 1-805-893-4530

E-mail: blythe@magic.ucsb.edu

Boettcher, Stefan S.

Department of Geological Sciences

University of Texas at Austin

Austin, TX 78712,

United States of America

Tel.: 1-512-471-8547,

Fax: 1-512-471-9425

E-mail: sboett@maestro.geo.utexas.edu

Bojar, Ana-Voica

Insitute für Geologie and Paläontologie

Karl-Franzens Universität

Heinrichstraße 26

A-8010 Graz, Austria

Fax: 43-316-382885

Brandon, Mark T.

Department of Geology and Geophysics

Kline Geology Laboratory

P.O. Box 6666

Yale University

New Haven, CT 06511,

United States of America

Braun, Jean-Jacques

CREGU BP23

54501 Vandoeuvre-les-Nancy

Cedex, France

Brix, Manfred R.
Ruhr-Universität Bochmum,

Fakultat fur, Geowissenschaften

Institu fur Geologie

Postfach 102148

Universitätsstraße 150

D-W 4630 Bochum 1, Germany

Tel.: 0049-234-700-3236,

Fax: 0049-234-709-4179

Brown, Roderick W.

Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1274,

Fax: 61-3-479-1272

E-mail: georwb@lure.latrobe.edu.au

Burchart, Jan

Institute of Geological Sciences

Polish Academy of Sciences

Zwirki i Wigury 93

02-089 Warsaw, Poland

Buck, Steve

Mobil North Sea Ltd.

Union Row

Aberdeen AB1 1SA, Scotland

Email: spbuck@abz.mobil.com

Carlson, William D.

Department of Geological Sciences

University of Texas at Austin

Austin, TX 78712,

United States of America

Tel.: 1-512-471-4770,

Fax: 1-512-471-9425

E-mail: wcarlson@ccwf.cc.utexas.edu

Carpena, Joelle

DSD-SCS-LGCA

C.E.N. Cadarache

13108 Saint Paul lez Durance CDX

France

Carpenter, Stephen B.

A505 Administration Bldg.

National Institute of Standards and Technology,

Gaithersburg, MD 20841,

United States of America

Carter, Andrew

Fission Track Research Group

Department of Geological Sciences

University College London

Gower Street

London WC1E 6BT

United Kingdom

Tel.: (0)171-380-7777 ext 2418

Fax: (0)171-813-2802

Email: a.carter@ucl.ac.uk

Cederbom, Charlotte

Institution of Geology,

Earth Sciences Centre

S-413 81 Gothenburg

Sweden

Tel.: +46 31 773 28 00

Fax: -28 49

Email: cederbom@geo.gu.se

Chambaudet, Alain

Universite de Franche-Comte

U.F.R. des Sciences et des Techniques

Laboratoire de Microanalyses Nucleaires

16 route de Gray

F-25030 Besancon Cedex, France

Coleman, Max

Postgraduate Research Institiue for Sedimentology,

The University of Reading,

PO Box 227, Whiteknights,

Reading, RG6 6AB,

United Kingdom

Cloos, Mark

Department of Geological Sciences

University of Texas at Austin

Austin, TX 78712,

United States of America

Tel.: 1-512-471-4170,

Fax: 1-512-471-9425

Email: cloos@maestro.geo.utexas.edu

Corrigan, Jeff D.

ARCO Exploration and Production Technology

2300 W. Plano Parkway

Plano, TX 75075,

United States of America

Tel.: 1-214-509-4090

Email: dprjdc@arco.com

Coyle, David A.

Hirschstraße 8/1

D-7465 Geislingen, Germany

Tel.: +49-7433-6338

E-mail:

dcoyle@goanna.mpi-hd.mpg.de

Crowley, Kevin, D.

Associate Director

Board on Radioactive

Waste Management,

National Academy of Sciences

National Research Council

2001 Wisconsin Avenue, N.W.

Washington, D.C. 20007,

United States of America

Tel.: 1-202-334-3066,

Fax: 1-202-334-3077

Email: KCROWLEY@NAS.EDU

Currie, Lisel

Geological Survey of Canada

100 West Vender St

Vancouver, BC, Canada, V6B1R8

Email: lcurrie@gsc.emr.ca

Danhara, Tohru

Kyoto Fission-Track Co.

Umezukita-machi 33

Ukyo-ku, Kyoto 615, Japan

Tel.: 81-75-881-2103,

Fax: 81-75-871-8044

De Corte, Frans

Institute for Nuclear Sciences

University of Gent

Proeftuinstraat 86

B-9000 Gent, Belgium

Decker, John E.

ARCO Alaska, Inc.

ATO 1418, 700 G.St.,

Anchorage, AK 99501,

United States of America

Tel.: 1-907-265-1521,

Fax: 1-907-265-1515

Email: jdecker1@is.arco.com

De Wispelaere, Antoine

University Gent

Institute for Nuclear Sciences

Proeftuinstraat, 86

B-9000 Gent, Belgium

Tel.: +32-9-264-6627,

Fax: +32-9-264-6699

Email: dewispelaere@inwchem.rug.ac.be

De Wit, M.C.J.

American Research Laboratories (Pty) Limited

PO Box 106 Crown Mines 2025

Johannesburg, South Africa

Dodson, Martin H., Ph.D.

Department of Earth Sciences

University of Leeds

Leeds, LS2 9JT, United Kingdom

Dokka, Roy K.

Department of Geology

Louisiana State University

Baton Rouge, LA 70803,

United States of America

Tel.: 1-504-388-2975

Donelick, Raymond A.

Donelick Analytical, Incorporated

4819 Katy-Hockley Road

Katy, TX 77493

United States of America

Tel.: 1-713-371-3346,

Fax: 1-713-371-0133

Email: 72762.1465@compuserve.com

Dorighel, Olivier

Groupe de Geophysique Nucleaire

Universite Joseph Fourier

Institut Dolomieu

15, Rue Maurice - Gignoux

38031 Grenoble Cedex, France

Duddy, Ian R.

Geotrack International,

P.O. Box 4120

Melbourne University

Victoria 3052, Australia

Tel.: +61-3-344-7214,

Fax: +61-3-347-5938

Dumitru, Trevor A.

Department of Geology,

Stanford University

Stanford, CA 94305-2115,

United States of America

Tel.: 1-415-725-6155,

Fax: 1-415-725-6155

E-mail: trevor@pangea.stanford.edu

Duncan, Alasdair

BP Exploration

PG8G (2/4S W10)

301 St. Vincent Street

Glasgow, G2 5DD, Scotland,

United Kingdom

Dunkl, Istvan

Universitaet Tuebingen

Institut und Museum fuer

Geologie und Palaeontologie

Sigwartstrasse 10

D-72076 Tuebingen

Tel.: +49 7071 29-72489,

Fax: +49 7071 5059

E-mail: dunkl@uni-tuebingen.de

Durrani, Saeed A.

School of Physics and Space Research,

University of Birmingham,

Birmingham B15 2TT,

United Kingdom

Tel.: +44-21-414-4691/4655

Fax: +44-21-414-4693

Eby, G. Nelson

Department of Earth Sciences

University of Massachusetts

Lowell, MA 01854,

United States of America

Tel.: 1-508-934-3907,

Fax: 1-508-934-3003

E-mail: ebyn@woods.ulowell.edu

Evarts, Russ

U.S. Geological Survey

345 Middlefield Road

Mail Stop 999

Menlo Park, CA 94025,

United States of America

Fayon, Annia K.

Box 871404

Department of Geology

Arizona State University

Tempe, AZ 85287-1404,

United States of America

Tel.: 1-602-965-5081,

Fax: 1-602-965-8102

E-mail: annia.fayon@asu.edu

Fisher, David E.

Department of Geological Sciences

University of Miami

Miami, FL 33124-0401,

United States of America

Tel.: 1-305-284-3254,

Fax: 1-305-284-4258

Fitzgerald, Paul G.

Department of Geosciences

University of Arizona,

Tucson, AZ 85721,

United States of America

Tel.: 1-602-621-4052,

Fax: 1-602-621-2672

E-mail: kiwi@sapphire.geo.arizona.edu

Fleischer, Robert L.

Department of Earth and Envir.Sciences

West Hall,

Rensselaer Polytechnic Institute

Troy, NY 12180-3590,

United States of America

Tel.: 1-518-276-8523,

Fax: 1-518-276-8627

Foland, Sara S.

Amoco Production Company

1670 Broadway

P.O. Box 800

Denver, CO 80201,

United States of America

Foster, David A.

VIEPS, Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1516,

Fax: 61-3-479-1272

E-mail: dfoster@mojave.latrobe.edu.au

Fugenschuh, Bernhard

Geologisches Institut

University of Basel, Basel, Switzerland

Galbraith, Rex F.

Department of Statistical Science

University College, Gower Street

London, WC1E 6BT,

United Kingdom

Gallagher, Kerry.

Department of Geology

Imperial College,

Prince Consort Road,

London, SW7 2BT.

United Kingdom

Tel: 0171-594-6424

Fax: 0171-594-6464

e-mail: kerry@ic.ac.uk

Ganzawa, Yoshiro

Hokkaido University of Education

1-2 Hachiman-cho

Hakodate, 040, Japan

Tel.: 81-0138-41-1121,

Fax: 81-0138-42-3982

Garver, John I.

Department of Geology

Union College

Schenectady, NY 12308,

United States of America

Tel.: 1-518-370-6517,

Fax: 1-518-370-6789

E-mail: garverj@gar.union.edu

George, Pete, Ph.D.

Department of Geological Sciences

University of Texas at Austin

Austin, TX 78712,

United States of America

Gibson, Helen

Geotrack International

P.O. Box 4120

Melbourne University

Victoria 3052, Australia

Tel.: +61-3-344-7214,

Fax: +61-3-347-5938

Giegengack, Robert

Geology Department

University of Pennsylvania

Philadelphia, PA 19104-6316,

United States of America

Giger, Matthias

Dammweg 27

3604 Thun, Switzerland

Tel.: 0041-33-368-227

Giles, Melvin R.

EPT-HM

Volmerlaan 8

Risswijk, Netherlands

Email: gilesm@siep.shell.com

or gilesfam@euronet.nl

Glasmacher, Ulrich

Geologisches Institut

RWTH - Aachen

Wuellnerstr.2

52062 Aachen, Germany

Fax.: 241-8888-151

Email: glasmacher@rwth-aachen.de

Gleadow, Andrew J. W.

Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-2649,

Fax: 61-3-479-1272

Green, Paul F.

Geotrack International

P.O. Box 4120

Melbourne University

Victoria 3052, Australia

Tel.: +61-3-344-7214,

Fax: +61-3-347-5938

Grist, Alexander

Department of Earth Sciences

Dalhousie University

Halifax, Nova Scotia, B3H 3J5, Canada

Tel.: 1-902-494-2372,

Fax: 1-902-494-6889

Grivet, Manuel

Universite de Franche-Comte

U.F.R. des Sciences et des Techniques

Laboratoire de Microanalyses Nucleaires

16, route de Gray

F-25030 Besancon Cedex, France

Guglielmetti, Alessandra

Instituto di Fisica Generale Applicata

Via Celoria 15

20133 Milano, Italy

Email: guglielmetti@mi.infn.it

Gunnell, Yanni

Laboratoire de Geographie Physique,

URA, 1562, CNRS,

Univesité Blaise-Pascal,

29 Bvd. Gergovia, 63037,

Clermont Ferrand, CEDEX 1

France

Hadler, Julio C.

Depto. Raios Cosmicos e Cronologia

Inst de Fisica - UNICAMP, CP 6165

13081 Campinas, SP, Brazil

Hansen, Kirsten

Geologisk Centralinstitut

Oster Volgrade 10, DK-1350

Kobenhavn K, Denmark

Tel.: 45-31-42-18-94 (home),

Fax: 45-33-14-84-33

Harman, Rebecca

Department of Geology

Imperial College,

London, SW7 2BT.

United Kingdom

Tel.: (0171) 589-5111 ext. 56411

Email: r.harman@ic.ac.uk

Harrison, Mark T.

Department of Earth and Space Sciences

University of California,

Los Angeles

Los Angeles, CA 90024,

United States of America

Hasebe, Noriko

Department of Earth Sciences

Faculty of Science

Kanazawa University

Kanazawa 920-11, Japan

Tel.: 81-762-64-5727,

Fax: 81-762-64-5764

Email: hasebe@kenroku.ipc.kanazawa- u.ac.jp

Hashemi-Nezhad, S.R.

Department of Physics

Faculty of Science

Tabriz University

Tabriz, Iran

Hayashi, Masao

Kyushu Sangyo University

Fukuoka 813, Japan

Tel.: 092-673-5883,

Fax: 092-673-5899

Hegarty, Kerry A.

Geotrack International

PO Box 4120

Melbourne University

Victoria 3052, Australia

Tel.: 61-3-344-7214,

Fax: 61-3-347-5938

Hejl, Ewald R.

Institut fur Geologie und Palaontologie der Universitat

Salzburg, Hellbrunnerstraße 34/III

A-5020 Salzburg, Austria

Tel.: 0662-8044-5437/5400,

Fax: 0662-8044-5010

Email: ewald.hejl@mh.sbg.ac.at

Hill, Kevin C.

VIEPS, Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1273,

Fax: 61-3-479-1272

E-mail: geokch@lure.latrobe.edu.au

Himeno, Osamu

Dept. of Mining Eng

Kyyushu Univerity

Hakozaki, Fukuuka 812-81, Japan

Tel.: 092-642-3635

Email: himeno@mine.kyushu-u.ac.jp

Honda, Teruyyki, Ph.D.

Atomic Energy Research Laboratory

Musashi Institute of Technology

Kawasaki 215, Japan

Hungerbuhler, Dominik

Department Erdwissenschaften

ETH-Zentrum

CH-8092, Zurich, Switzerland

Hurford, Anthony J., Ph.D.

Research School of Geological Sciences

University and Birbeck Colleges,

Gower Street

London WC1E 6BT,

United Kingdom

Tel.: +41-71-380-7704 or

+44-71-387-7050 (Lab)

Fax: +44-71-388-7614

Issler, Dale R.

Geological Survey of Canada

Institute of Sedimentary and Petroleum Geology

3303-33rd St., NW

Calgary, Alberta, T2L 2A7, Canada

Tel.: 1-403-292-7172,

Fax: 1-403-292-5377

Ito, Hisatoshi

Central Research Institute of

Electric Power Industry (CRIEPI)

1646 Abiko, Abiko city,

Chiba, 270-11, JAPAN

Tel.: 0471-82-1181 ex) 8525

Fax: 0471-83-3182,

International 81-471-83-3182

Email: ito_hisa@abiko.denken.or.jp

Iwano, Hideki

Kyoto Fission-Track Co.

44-4 Minamitaji-cho

Omiya Kita-ku, Kyoto 603, Japan

Tel.: 81-75-881-2103,

Fax: 81-75-871-8044

Johnson, Kit

Fission Track Research Group

Department of Geological Sciences

University College London

Gower Street

London WC1E 6BT

Tel.: (0)171-380-7777 ext 2418

Fax: (0)171-813-2802

Email: kit.johnson@ucl.ac.uk

Johnson, Mark

U.S. Geological Survey

345 Middlefield Road

Mail Stop 999

Menlo Park, CA 94025,

United States of America

Jonckheere, R.

Laboratorium voor Aardkunde

Universiteit Gent

Krijgslaam 281

B-9000, Gent, Belgium

Kamp, Peter J., Ph.D.

Department of Earth Sciences

University of Waikato

Hamilton 2001, New Zealand

Tel.: 64-7-856-2889,

Fax: 64-7-856-0115

Kasuya, Masao

Kyoto Fission-Track Co.

Umezukita-machi 33

Ukyo-ku, Kyoto 615, Japan

Tel.: 81-75-881-2103,

Fax: 81-75-871-8044

Kelley, Shari A.

Department of Earth and Envir. Sciences

New Mexico Tech

Soccoro, NM 87544,

United States of America

Tel.: (505) 661-6171

Email: kelley@griffey.nmt.edu

or sakelley@ix.netcom.com

Kendrick, Dan

VIEPS, Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1273,

Fax: 61-3-479-1272

E-mail: geordk@lure.latrobe.edu.au

Ketcham, Richard

Department of Geological Sciences

University of Texas at Austin

Austin, TX 78712,

United States of America

Tel.: 1-512-471-5763,

Fax: 1-512-471-9425

E-mail: richk@maestro.geo.utexas.edu

Kohn, Barry P.

VIEPS, Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1516/1274,

Fax: 61-3-479-1272

E-mail: geobpk@lure.latrobe.edu.au

Koshimizu, Satoshi

Institute for Atomic Energy

Rikkyo University

Nagasaka 2-5-1, Yokosuka,

240-01, Japan

Tel.: 81-468-56-3131,

Fax: 81-468-56-7576

Kowallis, Bart Joseph

Department of Geology

Brigham Young University

Provo, UT 84602,

United States of America

Tel.: 1-801-378-2467,

Fax: 1-801-378-2265

Krochmal, Michael

Autoscan Systems Pty. Ltd.

PO Box 112, Ormond,

Ormond, Victoria 3204, Australia

Wk. Phone.: + 61 39 596 8065

Hm. Phone.: + 61 39 578 9124

Wk. FAX : + 61 39 596 8369

Email: kroch@autoscan.com.au

HomePage:

http://www.autoscan.com.au/~autos can

Lal, Nand

Department of Geophysics

Kurukshetra University

Kurukshetra-132119, India

Laslett, Geoff M., Ph.D.

CSIRO Division of Mathematics & Statistics

Private Bag 10, Clayton South MDC,

Clayton, VICTORIA 3169, Australia

Tel.: +61 3 9545 8018

Fax: +61 3 9545 8080

Email: Geoff.Laslett@dms.csiro.au

Lewis, Cherry L.E.

Robertson Research International Ltd.

Llanrhos, Llandudno, Gwynedd,

North Wales, LL30 1SA,

United Kingdom

Linn, Jon

University of Kansas

Department of Geology

120 Lindley Hall

Lawrence, KS 66045,

United States of America

E-mail: jklinn@kuhub.cc.ukans.edu

Lisker, Frank

FB5 - Geowissenschaften

Universitaet Bremen

PF 330440 Bremen, Germany

Email: flisker@geopol.uni-bremen.de

Märk, E.

Hohrere technische Bundeslehr-

und Versuchsanstalt Anichstr.

26-28

A 6020 Innsbruck, Austria

Märk, T. D.

Abt. f. Kernphysik u. Gaselektronik

Institut f. Experimentalphysik

Leopold Franzens Universität

A 6020 Innsbruck, Austria

Marshallsea, Susan

Geotrack International

P.O. Box 4120

Melbourne University

Victoria 3052, Australia

Tel.: +61-3-344-7214,

Fax: +61-3-347-5938

Matsuda, Takaaki

Himeji Institute of Technology

2167, Shosha Himeji

Hyogo 671-22, Japan

Maze, Will B.

Exxon Production Research

P.O. Box 2189

Houston, TX 77252-2189,

United States of America

Tel.: 1-713-965-7223,

Fax: 1-713-965-7951

McCorkell, Robert

CANMET, Mineral Technology Branch

Energy, Mines and Resources

555 Booth Street

Ottawa, Ontario K1A 0G1, Canada

McCulloh, Thane H.

7136 Aberdeen

Dallas, TX 75230,

United States of America

Tel.: 1-214-691-6809

Meyer, Arnaud J.

ELF AQUITAINE-CSTJF L1/010

64018 Pau Cedex, France

Miller, Donald S.

Department of Earth and Envir. Sciences

Rensselaer Polytechnic University

Troy, NY 12180-3590,

United States of America.

Tel.: 1-518-276-8523,

Fax: 1-518-276-8627

E-mail: don-miller@mts.rpi.edu

Miller, Elizabeth L.

Department of Geology

Stanford University

Stanford, CA 94305-2115,

United States of America

Tel.: 1-415-723-1149,

Fax: 1-415-725-2199

E-mail: miller@pangea.stanford.edu

Mitchell, Melinda M.

Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1274,

Fax: 61-3-479-1272

E-mail: geomm@lure.latrobe.edu.au

Moore, Marilyn

Geotrack International

P.O. Box 4120

Melbourne University

Victoria 3052, Australia

Tel.: +61-3-344-7214,

Fax: +61-3-347-5938

Mora, Jorge

Department of Geological Science

College of Science and Mathematics

Earth Sciences 351

State University of New York

Albany, NY 12222,

United States of America

Mora, Jorge

Escuela de Geologia

Minas y Geofisica

Facultad de Ingenieria

Universidad Central de Venezuela

Caracas, Venezuela

Murphy, John M.

Department of Geology and Geophysics

University of Wyoming

Laramie, WY 82071,

United States of America

Tel.: 1- 307-766-5435

E-mail: geojm@plains.uwyo.edu

Naeser, Charles W.

U.S. Geological Survey

926a National Center

Reston, VA 22092,

United States of America

Tel.: 1-703 648-6964,

Fax: 1-703-648-6953

E-mail: cnaeser@usgs.gov

Naeser, Nancy D.

U.S. Geological Survey

926a National Center

Reston, VA 22092,

United States of America

Tel.: 1-703 648-5328,

Fax: 1-703 648-6953

Nishimura, Susumu, D.Sc.

Department of Geology and Mineralogy

Faculty of Science

Kyoto University

Kyoto 606, Japan

Tel.: 81-75-753-4150,

Fax: 81-75-753-4189

Noble, Wayne P.

C/O Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-2630,

Fax: 61-3-479-1272

E-mail: georwpn@lure.latrobe.edu.au

Oddone, Massimo

Dipartimento di Chimica Generale

viale Taramelli, 12

27100 Pavia, Italy

Ohira, Hiroto

Department of Geoscience,

Shimane University,

Matsue 690, Japan.

Tel.: 81-852-32-6465

Fax: 81-852-32-6469

E-mail ohira@botan.shimane-u.ac.jp

Olesch, Martin

University Bremen

FB 5 Geowissenschaften

Postfach 330 440

2800 Bremen, 00071-00 Germany

Tel.: +49-421-2183940,

Fax: +49-421-2183993

Omar, Gomaa I.

Geology Department

University of Pennsylvania

Philadelphia, PA 19104,

United States of America

Ono, Masako

Hokkaido University

Kyoyo-chigaku

N17-W8, Kita-ku

Sapporo, 060, Japan

Tel.: 81-11-716-2111, ext. 5309

Fax: 81-11-736-3290

Email: mo@epms.hokudai.ac.jp

O'Sullivan, Andrea J.

VIEPS, Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1274,

Fax: 61-3-479-1272

E-mail: geoajo@lure.latrobe.edu.au

O'Sullivan, Paul B.

Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-9479-3517,

Fax: 61-3-9479-1272;

E-mail: pos@mojave.latrobe.edu.au

Pagel, Maurice

CREGU, B.P. 23

54501 Vandoeuvre-Les-Nancy, France

Tel.: 33-83-44-19-00,

Fax: 33-83-44-00-20

Pan , Yun

Department of Geological Sciences

University of SUNY at Albany

NY 12222, United States of America

Paul, Tracy A.

Department of Chemistry

Arizona State University

Tempe,. AZ 85287-1404,

United States of America

Tel.: 1-602-921-1306

E-mail: agtxp@asuacad

Pengji, Zhai

Institute of High Energy Physics

Academia Sinica

P.O. Box 2732

Beijing 100080,

People's Republic of China

Perelygin, V. P. Dr.

Flerov Laboratory of Nuclear Reactions

Joint Institute for Nuclear Research,

Dubna Head Post Office, Box 79

101 000 Moscow

Russian Federation

Petford, N.

Bullard Lab.

Department of Earth Sciences

University of Cambridge

Madingly Rise

Cambridge, CB3 0DZ,

United Kingdom

Poupeau, Gerard R.

Universite Joseph Fourier

Institut Dolomieu

15, Rue Maurice - Gignoux

38031 Grenoble Cedex, France

Tel.: 33-76-63-59-30,

Fax: 33-76-87-82-43

Prashad, Rajinder

Fission Track Laboratory

Special Research Group

ERD Building, 3RD Floor

KDM Institute of Petroleum Exploration

Oil and Natural Gas Corporation

Dehradun, INDIA

Price, P. Buford

Department of Physics

University of California

Berkeley, CA 94720,

United States of America

Tel.: 1-510-642-4982,

Fax: 1-510-643-8497

E-mail: price@lbl.qov

Puch, Thomas

Insitute für Geologie and Paläontologie,

Karl-Franzens Universität

Heinrichstraße 26

A-8010 Graz, Austria

Fax: 43-316-382885

Qvale, Henning

Institute for Energy Technology

P.O. Box 40

N 2007, Kjeller, Norway

Tel.: +47-63-80-61-22,

Fax: +47-63-81-55-53

E-mail: hq@varney.ite.no

Rahn, Meinert

Institut fuer Mineralogie, Petrologie und Geochemie

University of Freiburg

Albertstrasse 23b

79104 Freiburg, Germany

Tel: 49-761-2036416,

Fax: 49-761-2036407

Email:meinert@mis01.mineralogie.uni- freiburg.de

Ratschbacher, Lothar

Institut fuer Geologie

Universitaet Wuerzburg

Pleicherwall 1

D-97070 Wuerzburg, Germany

Tel. +49-931-312580

Fax. +49-931-57705

e-mail. l.ratschbacher@rzbox.uni- wuerzburg.de

Ravenhurst, Casey E.

Department of Geology and Geography

University of Massachusetts

Amherst MA 01003,

United States of America

E-mail: CRAVENHU@smith.smith.edu

Raza, Asaf

C/O Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-1274,

Fax: 61-3-479-1272

E-mail: geoar@lure.latrobe.edu.au

Rebetez, Michel

Universite de Franche-Comte

U.F.R. des Sciences et des Techniques

Laboratoire de Microanalyses Nucleaires

16, route de Gray

F-25030 Besancon Cedex, France

Redfield, Thomas F.

Ph.D (Arizona State

University, 1994)

Technical Exploration Services

5 Frost Court

Mill Valley, CA 94941,

United States of America

Roden-Tice, Mary, K.

Center for Earth & Envir. Science

SUNY Plattsburgh

Plattsburgh, NY 12901,

United States of America

Tel.: 1-518-564-2019,

Fax: 1-518-564-3152

Saini, Hari Singh

Department of Radiometric Dating

Birbal Sahni Institute of Paleobotany

53 University Road

Post Box 106

Lucknow 226 007, India

Sandhu, Amanjit S.

Department of Physics

Guru Nanak University

Amritsar 143005, India

Fax.: 91-183-258820

Email: cse@gndu.ernet.in

Schwarze, Phillip

Dept. of Earth Sciences

Monash University

Wellington RD

Clayton, Victoria 3168

Australia

Email: phil@artemis.earth.monash.edu.au

Seward, Diane

Department Erdwissenschaften

ETH-Zentrum

CH-8092, Zurich, Switzerland

Tel.: 0041-1-252-2227,

Fax: 0041-1-252-7008

Email: diane@erdw.ethz.ch

Shane, Phil

Geology/School of Environmental

and Marine Sciences

University of Auckland

Tamaki Campus

Private Bag 92019

Auckland, New Zealand

Phone 64-9-373 7599 ext. 6821

Fax 64-9-373 7042

Shunsheng, Liu

Changsha Institut of Geotectonics

Academia Sinica

Changsha 410013

Hunan Province, PR China

Tel.: 86-731-8859165

Fax: 86-731-8859137

Siddall, Ruth

Fission Track Research Group

Geological Sciences

University College London

Gower St

London WC1E-6BT, United Kingdom

Tel.: 0171-380-7777 ext. 2758 office

Tel.: 0171-380-7777ext. 2418 lab

Fax: 0171-388-7614

E-mail: r.siddall@ucl.ac.uk

Singh, Gurinder

Department of Physics

Guru Nank Dev University

Amritsar 143005, India

Sleadon, Andrew Jan

Department of Geology

La Trobe University

Bundoora, Victoria 3083, Australia

Tel.: 61-3-479-2649,

Fax: 61-3-479-1272

E-mail: seoajs@lure.latrobe.edu.au

Sobel, Ed

Institut fuer Geowissenschaften

Universität Potsdam Tel: (49) (0331) 977-2904 or -2047 Fax: (49) (0331) 977-2087

Postfach 60 15 53 D-14415 Potsdam

email: sobel@rz.uni-potsdam.de

Sohrabi, Mehdi, Ph.D.

Radiation Protection Department

Atomic Energy Organization of Iran

P.O. Box 14155-4494

Tehran, Iran

Sorkhabi, Rasoul B.

Department of Geology

Arizona State University

Tempe, AZ 85287-1404,

United States of America

Tel.: 1-602-965-9852/5081,

Fax: 1-602-965-8102

E-mail: idrbs@asuvm.inre.asu.edu

Stapel, Gerco

Inst. voor Aardwerenschappen

Vrije Universiteit

De Boelenlaan 1085

1081 HV Amsterdam, Netherlands

Email: stag@geo.vu.nl

Steckler, Michael S.

Lamont-Doherty Geological Observatory

Palisades, NY 10964,

United States of America

Tel.: 1-914-365-8479,

Fax: 1-914-365-0718

E-mail: steckler@lamont.idgo.columbia.edu

Steinmann, Michael

Department Erdwissenschaften

ETH-Zentrum

CH-8092, Zurich, Switzerland

Stiberg, Jan-Petter

Institute for Energy Technology

P.O. Box 40, N 2007

Kjeller, Norway

Tel.: +47-63-80-61-22,

Fax: +47-63-81-55-53

Stockli, Danny

Dept. Geological & Environ. Sciences

Stanford University

Stanford, CA 94305-2115

U.S.A.

Tel.: 1-415-725-6155

Fax: 1-415-725-6155

Email: danny@pangea.stanford.edu

Stockmal, Glen S.

Geological Survey of Canada

Institute of Sedimentography and Petroleum Geology

3303-33rd Street, N.W.

Calgary, Alberta T2L 2A7, Canada

Tel.: 1-403-292-7173,

Fax: 1-403-292-5377

Storzer, Dieter

Museum d'histoire naturelle

Laboratoire de Mineralogie

61 rue Buffon,

75005 Paris, France

Stump, Edmund

Department of Geology

Arizona State University

Tempe, AZ 85287-1404,

United States of America

Tel.: 1-602-965-3971/5081,

Fax: 1-602-965-8102

E-mail: ateds@asuacad.

Sumii, Tomoaki

Isotope Geoscience Section

Geochemistry Department

Geological Survey of Japan

1-1-3 Higashi,

Tsukuba, 305, Japan

Tel.: 81-298-54-3558,

Fax: 81-298-54-3533

Email: sumii@gsj.go.jp

Summerfield, Michael

Department of Geography

School of Earth Sciences

University of Edinburgh

Edinburgh EH8 9XP, United Kingdom

Tel.: +44-31-650-2519

Sun, Shaohua

Changsha Institut of Geotectonics

Academia Sinica

Changsha 410013

Hunan Province, PR China

Tel.: 86-731-8887945 (home)

Fax: 86-731-8859137

Email: shaohua@ms.csig.ac.cn

Suzuki, Masao

Rikkyo University

34-1 Nishi Ikebukuro

3-Chome, Toshima-ku

Tokyo 171, Japan

Tagami, Takahiro

Department of Geology and Mineralogy

Faculty of Science

Kyoto University

Kyoto 606, Japan

Tel.: 81-75-753-4153,

Fax: 81-75-753-4189

Talbot, James

1709 Overlook Drive,

Grapevine, TX 76051,

United States of America

Thomson, Stuart

Institut für Geologie

Ruhr-Universität Bochum

Universitätsstraße 150

P.O. Box 102148

Bochum 44721, Germany

Toro, Gloria

Universidad EAFIT

A.A. 3300

Medellin, Colombia

Email: gtoro@sigma.eafit.edu.co

Upton, David

Fission Track Research Group

Department of Geological Sciences

University College London

Gower Street

London WC1E 6BT

Phone: (0)171-380-7777 ext 2418

Fax: (0)171-813-2802

Vance, Joseph, A.

Department of Geological Sciences

University of Washington

Seattle, WA 98195,

United States of America

Van den haute, Peter

Geologisch Instituut

Rijiks Universiteit

B-9000 Gent, Belgium

Tel: +32-0-9-264/4592 or 6627,

Fax: +32-0-9-264-4984

E-mail: FTWORK@inwchem.rug.ac.be

Van der Wateren, F. M.

Institue for Earth Science,

Vrije Universiteit,

De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands

Vercoutere, Caroline

Geologisch Instituut

Rijiks Universiteit

B-9000 Gent, Belgium

Viola, Gulio

Geologisches Institut

Sonneggstrasse 5

ETH-Zentrum

CH-8092, Zurich, Switzerland

Tel.: 0041-1-252-2227,

Fax: 0041-1-252-7008

Email: gulio@erdw.ethz.ch

Virk, H. S.

Department of Physics

Guru Nanak Dev University

Amritsar-143005, India

Wadatsumi, Kiyoshi

Department of Geosciences

Faculty of Science

Osaka City University

3-3-138 Sugimoto

Sumiyoshi-ku

Osaka 558, Japan

Wagner, Gunther A.

Max-Planck-Institut fur Kernphysik

Saupfercheckweg, D-6900

Heidelberg, Germany

Wagner, Martin

Institut fur Petrographie und Geochemie,

Universität Karlsruhe

Kaiserstr. 12

D-7500 Karlsruhe, Germany

Walgenwitz, Frederic

ELF AQUITAINE-CSTJF L1/010

64018 Pau Cedex, France

Walker, J. D.

of Technology, 1985)

Department of Geology

University of Kansas

120 Lindley Hall

Lawrence, KS 66045-2969,

United States of America

Walker, Robert M.

McDonnell Center for the Space Sciences

Campus Mail 1105

Washington University

1 Brookings Drive

St. Louis, MO 63130,

United States of America

Tel.: 1-314-935-6225,

Fax: 1-314-935-6219

E-mail: brw@wuphys.wustl.edu

Walter, Bob

Institute of Human Origins

1288 Ninth Street

Berkely, CA 94709-1211,

United States of America

Tel.: 1-510-525-0500,

Fax: 1-510-525-0668

Email: bwalter@iho.org

Waraich, R. S.

KDM Institute of Petroleum Exploration

Oil & Natural Gas Corporation LTD.

Dehradun, India

Watanabe, Koichiro

Department of Mining

Faculty of Engineering

Kyushu University,

36 Hakozaki, Fukuoka 812, Japan

Tel.: 81-92-642-3634

Email: wat@mine.kyushu-u.ac.jp

Weiland, Richard J.

Department of Geological Sciences

University of Texas at Austin

Austin, TX 78712

United States of America

Tel.: 1-512-471-8547,

Fax: 1-512-471-9425

E-mail: rweiland@maestro.geo.utexas.edu

Westgate, John A., Ph.D.

Department of Geology

University of Toronto

Scarborough Campus

Scarborough, Ontario

M1C 1A4, Canada

Yamashita, Tohru

Kyoto Fission-Track Co.

Umezukita-machi 33

Ukyo-ku, Kyoto 615, Japan

Tel.: 81-75-881-2103,

Fax: 81-75-871-8044

Yegingil, Zehra

Cukurova University

Arts-Sciences Faculty

Physics Department

P.O. Box 171, 01330 Adana, Turkey

Zattin, Massimiliano

Dipartimento di Geologia

Universita di Bologna

Bologna, Italy

Email: zattin@geomin.unibo.it

Zhao, Yunlong

Beijing Research Institute of

Uranium Geology

P.O. Box 764

Beijing 100029,

Peoples Republic of China

Zeitler, Peter K.

Department of Earth &

Environmental Sciences

Lehigh University

31 Williams Drive

Bethlehem, PA 18015-3188,

United States of America

Tel.: 1-215-758-3671,

Fax: 1-215-758-3677

E-mail: pkz0@lehigh.edu

Zentilli, Marcos,

Department of Earth Sciences

Dalhousie University

Halifax, Nova Scotia, B3H 3J5, Canada

Tel.: 1-902-494-3873,

Fax: 1-902-494-6889

E-mail: zentilli@ac.dal.ca

Zimmerman, Robert Allen

U.S. Geological Survey, MS 905

Box 25046, Federal Center

Denver, CO 80225,

United States of America

Tel.: 1-303-236-5626,

Fax: 1-303-236-5603

Email:rzimm@greenwood.ct.usgs.gov

Zuffa, Gian G.

Dipartimento di Scienze Geologiche

Universita di Bologna

via Zamboni 67

40137 Bologna, Italy

Tel.: 39-51354536

E-mail: zuffa@Dogon.geomin.unibo.it


"OFF TRACKTM" ... :)

by an anonymous tracker from down-under

(ed. chicken!)

We all know that Geotrack Int. Pty. Ltd has "Trademarked" "AFTA" and that they search out and destroy anyone who uses the term (there must be a lot of Chinese authors who had better watch out). For fun, a tracker recently searched the World Wide Web for evidence that "AFTA" was being used. What she found was:

AFTATM (meaning "apatite fission track analysis" by Geotrack Int. Pty. Ltd) does not come up anywhere on a home page. However, other home pages using "AFTA" include:

Australian Federation of Travel Agents Ltd. (http://www.afta.com.au/)

Australian Freestyle Taekwondo Academy

(http://www.aftataekwondo.com.au/)

Arts For The Aging, Inc.

(http://www.aftaarts.org/)

Do they need to worry also?

(ed. Off TrackTM "humor" expressed in On Track is that of anonymous authors and does not necessarily reflect that of the editor of On Track. BTW this new section was born and the term "Off TrackTM" was coined and of course "trademarked" by Rebecca Harman et al. at a bar in Gent Belgium...... :)


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Our stage systems are based on a highly-reliable, high-precision Kinetek&tm; computer-automated microscope scanning stage. Several hundred Kinetek stages are currently in operation, mainly in the microelectronics industry. Compatible with almost any brand of microscope. Use of this popular, general purpose stage significantly reduces the system cost. System also includes a high-quality Calcomp&tm; 12x12" digitizing tablet. Assembly to full operational status generally requires only a few days.

Outstanding Software:

Software is a complete, highly sophisticated Apple Macintosh program developed with careful attention to all aspects of microscope work. Fully integrates track counting, track length measurement, slide scanning, and file management functions. Moves precisely from grain to mica print in 3 seconds. Very user friendly. Fully functional even with the lowest cost Macintosh models and with the MS-Windows compatible Macintoshes.

Innovative, Highly-Intuitive Stage Control System:

Stage is driven primarily with the digitizing tablet cursor rather than a joystick. For example, to center a grain or track, just superimpose the cursor on it, push a button, and the stage automatically centers it. This avoids tedious manual centering via the joystick. Most software commands are driven from the cursor buttons, which are easily distinguished by feel, so there is no need to look away from the eyepieces to the computer screen or keyboard.

Fission Track Laboratories Using the System:


*Stanford University, Stanford, California, installed in 1991


*University of California, Santa Barbara, California, installed in 1992


*ARCO Exploration and Production Technology, Plano, Texas, installed in 1992


*Universität Bremen, Bremen, Germany, installed in 1993


*E.T.H., Zürich, Switzerland, installed in 1993 using a preexisting stage


*Kent State University, Kent, Ohio, installed in 1993


*University of Wyoming, Laramie, Wyoming, installed in 1993


*University of Arizona, Tucson, Arizona, installed in 1993


*Max-Planck-Institut, Heidelberg, Germany, installed in 1993 using a preexisting stage


*Union College, Schenectady, New York, installed in 1994


*Monash University, Melbourne, Australia, installed in 1994 using a new Zeiss stage


*La Trobe University, Melbourne, Australia, installed in 1994 using two new Zeiss stages


*University of Pennsylvania, Philadelphia, Pennsylvania, installed in 1995


*Universität Tübingen, Tübingen, Germany, installed in 1995


*Universidad Central de Venezuela, Caracas, Venezuela, installed in 1995


*Brigham Young University, Provo, Utah, installed in 1995


*Central Research Institute of the Electric Power Industry, Chiba, Japan, installed in 1995


*Universität Salzburg, Salzburg, Austria, installed in 1996


*University of Southern California, Los Angeles, California, installed in 1996


*E.T.H., Zürich, Switzerland, second system installed in 1996 using a preexisting stage


*Geologisk Centralinstitut, Copenhagen, Denmark, installed in 1996 using a preexisting stage


*University of Waikato, Hamilton, New Zealand, installed in 1996 using a preexisting stage

Detailed Information:

The system is described in a paper in Nuclear Tracks and Radiation Measurements, vol. 21, p. 575-580, Oct. 1993 (proceedings issue for the 1992 Workshop on Fission Track Thermochronology held in Philadelphia).

For Further Information Contact: Dr. Trevor Dumitru, 4100 Campana Drive, Palo Alto, California 94306, U.S.A., telephone (auto-switching voice and fax line): 1-415-725-6155 (number expected to change in mid or late 1997)