179

NOTES ON THE GEOLOGY
OF
NORTHWEST TEXAS.

By W. F. Cummins.

INTRODUCTION.

In submitting this report of the work done during the past year, I have thought it advisable to give a brief itinerary of the trip, in order to more definitely describe the localities visited and show their relation to each other.

It had been demonstrated during my previous trip to the Staked Plains that there were different epochs of the Tertiary represented in the strata, and that a correct understanding of their relations could only be secured by a systematic collection of the fossils and a complete stratigraphic section. It was known that the Loup Fork beds, with their well recognized fossils, occurred in places along the Canadian river, in the northern part of the Panhandle of Texas; that the Blanco beds, a terrane higher than the Loup Fork, were at Blanco Canyon; and that a still newer formation than the Blanco was situated to the west; yet their exact location and extent had not been definitely determined.

It was also desirable to have a more extensive collection from the Triassic formation, of which the principal outcrop in Texas is at the base of the eastern escarpment of the Staked Plains. I was also instructed to make a more extensive collection of the fossils from the various horizons of the Permian strata, giving special attention to the invertebrates and to the flora.

The route of travel was therefore selected so as to enable me to make consecutive observations of the stratigraphy of the Triassic, to visit the several localities where the Tertiary fossils were known to exist, as well as other localities likely to furnish fossils of that formation, and at the same time to collect fossils from the Triassic without making a special trip for that purpose, and then be in a position to go into the Permian with as little travel as possible.