Areal Geology of the Post-Paleozoic Surface of the Northwest Plains

Probably most of the area included in this report has been ex­amined to some extent by oil geologists, and most, if not all, of the important domes have been discovered and surveyed thoroughly. In parts of the area, the bedrock is covered by glacial drift or alluvium materi­al, but it is reasonable to believe that no new domal structure will be found. This means that surface examination alone will be insufficient in locating new oil fields, so future prospecting will be dependent, to a great extent, on studies of sub-surface stratigraphy.

Geology of the Tuxedo Mining District

The Tuxedo mining district lies fifteen miles west of Butte on the south east end of Deer Lodge valley. Prospecting and mining has been carried on in this district for about 20 years. As a result many pits have been dug, several adits have been driven, and two or three shallow shafts have been sunk.