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Throughout the region there is no serious want of conformity between the various geological divisions. On the contrary, they appear to graduate so easily from one to the other that it is often somewhat difficult to tell the exact line at which the actual change occurs. In most of the places where the contacts have been observed the exact limits of each are as yet approximations only, but the line will not in any case vary more than a few feet in either direction.

Throughout the greater portion of the area under consideration the overlying drift material has covered up the older formations to such an extent that the contacts between them are exposed at only a few places, chiefly in the few bluffs along the rivers flowing through the territory. They are also to be seen in a small number of the deeper railway cuttings.

Along the contact between the newer Eocene and the beds ascribed to the Miocene age there are indications at several places of extensive erosions having taken place prior to the deposition of the Miocene beds. These erosions appear to have the form of long, narrow arms of the sea or river channels, and are often several miles in length. The dip of the deposits occupying these buried channels varies slightly, both in angle and direction, from the beds forming the hills or shores of the channel. This variation does not, however, exceed a degree greater than from southeast to south, and may properly be accounted for by the action of tidal waters or rivers subject to overflow. Similar variations of dip and direction occur among the deposits forming the overflow lands of the present rivers.

The contacts between the overlying Quaternary gravels and sands and the underlying older deposits are, however, subject to no rule. These sands occur irregularly, both in areal extent and thickness, frequently lying upon the smooth surface of the bed beneath them, and then again filling up eroded depressions in the same beds.

While the whole of the details of these sections have not as yet been worked out it is believed that the following broad outlines of the work done are as nearly accurate as can be given until a thorough study has been made of the materials obtained during the course of the work. They may, therefore, be taken as approximately correct, and while all figures here given relative to the thickness and extent of any of the deposits may be looked upon as tentative only and subject to correction, it is believed that no great variation will take place between those given and those of the final results.

The relative thickness of the deposits found along the lines of the sections made are shown in the following generalized section: