Upper Cretaceous Sediment in Montana

Cretaceous sediments in Montana record events during a period of unusual geologic interest. After a long period of extensive submergence of the area during Jurassic time, came a period of varying continental and marine deposition with consequent variations in the types of sediments laid down. A study of these variations, their extent, and their cause has been the primary object of this thesis.

General Geology and Mines of Northwestern Montana

The five counties discussed in this paper compose the northernmost and westernmost counties in Montana. On the eastern boundary are Glacier National Park and the Continental Divide; on the southern boundary are Missoula and Powell counties; Idaho lies on the southwestern and western side; and the Canadian border lies along the northern edge. The region is on the Pacific Ocean side of the Rocky Mountains. Three major rivers, the Clark Fork, the Flathead, and the Kootenai drain this area into the Columbia River.

The Separation of Tungstic Oxide from Scheelite and its Subsequent Reduction with Hydrogen

The largest known deposits of tungsten ores occur in the continuation of the Indo-Malayan Mountains, which extends through Burma, Malaya, China, Japan, and Chosen. Production of tungsten concentrates was started in 1910 in Burma, and in 1911 this country was the world's largest producer. China produced but little until 1916, but has since supplied over fifty per cent of the world's requirements.

The Geology and Ore Deposits of the Ruby Gulch Mine

The Ruby Gulch Mine, owned and operated by the Ruby Gulch Mining Company, Zortman, Montana, is one of the most important low-grade gold producers in the state. Sit­uated in the Little Rocky Mountains, the mine has had an interesting history since its discovery shortly before the turn of the century.

Mayflower, Renova Basin, and South Boulder Creek Areas

In Montana at the turn of the century a great many men sought the riches buried in the earth's crust. Prospectors fanning out from Butte and other early Montana mining areas located veins at the Mayflower, Renova, and Gold Hill areas.

Geology of Upper Bear Gulch and Dry Boulder Creek Area Madison County, Montana

Potential gold mines lie high among the rugged peaks of the Tobacco Root Mountains of southwestern Montana. This is a region where little geologic work has been done, though extensive mine operations have been carried on, and valuable ore has been shipped.

The Geology and Mineral Deposits of British Columbia

The province of British Columbia, with an area of 359,279 square miles, includes a large part of the Canadian Cordillera that is the western mountains of Canada. It is the leading province of Canada in the production of lead, zinc, and silver, and third among the provinces in the output of gold, copper, and coal.

The Physiographic History of Western Montana and Northwestern Idaho

Millions of years of physiographic changes have conditioned us to the fact that our present drainage is a temporary feature. Rivers once flowing opposite to their present direction is not an unusual condition for physiographers to suggest.

A Mineral Dressing Study of the U.S. Grant Ore

This investigation concerns the development of a satis­factory method or extracting or concentrating gold and silver from the ores of the U. S. Grant Mine. The choice between applying an extractive process and one by which the valuable mineral constituents are concentrated depends on more than one factor.

The Amplifier - v. 3, no. 2

In this issue...Boeing Aircraft, Shell Oil Company, Hugo Pulju, mauled grizzly bear, Dean McAuliffe, Geology, Rocky Mountains, Coach Olsen, Petroleum Department

Geology 63: Geological Report of Senior Field Trip

The field work was conducted in areas adjacent to White­hall, Montana, as has been the custom for the past several years. Instruction in the proper use of the telescopic and open sight alidades, and the Brunton compass for surveying geologic features was given. Advantages of pacing and speed­ometer mapping were pointed out and used.

Geology of Montana

A vast amount of information has been published by many workers on particular features of the geology of the state of Montana, as well as on local geology of many smaller divi­sions. However, a satisfactory summary of the geology in general, which would include all phases of geology as they apply to the greater area of the entire state, has not been published.

The Fort Union Formation of Montana and Adjacent Areas

The Fort Union formation is one of the most import­ant and best known geologic formations of the northern Great Plains, and is found lying almost horizontal at the surface over large areas in this region.

The Christensen Sillimanite Deposit Southeast of Dillon, Montana

The minerals sillimanite, kyanite, andalusite, dumortierite, and topaz comprise a group of minerals whose high alumina content and physical properties are particularly desirable in the manufacture of refractory products. Sillimanite is the least plentiful of the minerals of this group, and for this reason it is not used extensively at the present time. However, it would be very desirable to the refractory industry if a suitable domestic source of supply could be established.

The Livingston Formation of the South Boulder Area

The Livingston formation is a thick succession of late Cretaceous lava flows, tuffs, and bedded water-laid volcanic detritus 200 miles long and 100 miles wide lying along the eastern margin of the Rocky Mountains in western Montana from Augusta to Yellowstone Park. It differs markedly within short distances in lithologic character and sequences, and the total thickness may exceed one mile in some places.