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.

Geology of the Butte Ore Deposit

Dr. John Dilles discusses the geochemistry of the porphyry Cu-Mo resource found at at Butte, Montana. The porphyry formed from dilute magmatic fluids that contained 1,000s of ppm Cu between 66 and 64 Ma, and at depths of ~8 km. The porphory is zoned from innermost Cu (Ag) ore; to mixed intermediate Cu (Zn, Ag) / Zn-MJn-Ag (Cu, Pb, Au) ore; to an outer Mn-Ag (Pb) ore that grades to barren quartz.

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 and Geological Structure of the Alberta and Saskatchewan Plains

Alberta, responsible for ninety per cent of Canada's output, had, by 1947 entered into her fifth year of production decline. Only ten per cent of Canada's oil requirements were secured from home fields. Ninety per cent had to be imported, mainly from the United States. How long could imports be maintained on present levels? During the year, the United States had started rationing; in one sector of its domain. Would this become general? If so, what was the answer for Canada?

Geology of the Lost Creek-Modesty Creek Area Deerlodge County, Montana

In 1915 the United States Geological Survey published a folio by Calkins and Emmons on the geology of the Philipsburg Quadrangle, which ad­joins the area now under study to the west. Geology of this portion of Montana had not been mapped previously; consequently the purpose of this thesis is to make a geological reconnais­sance of the stratigraphy and structure of the area.

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.

Geology and Ore Deposits of the Salt Chuck-Rush and Brown Mine Area Prince of Wales Island, Alaska

The Salt Chuck, Rush and Brown, and adjacent mines and claims form an area of approximately 15 square miles near the head of Kasaan Bay about 10 miles northwest of the village of Kasaan on Prince of Wales Island in southeastern Alaska. It is an area of moderate relief in which the hills rise from the water’s edge to heights of some 500 feet. Most of the area is covered with dense vegetation and muskeg.

The Geology and Ore Deposits of the Ermont Mines

The Ermont Mines are located sixteen miles northwest of Dillon, Montana, in section 35 of T.6S., R.11W. This is in the central part of Beaverhead County. They are considered to be in the Argenta min­ing district, the town of Argenta lying three miles to the northeast.

Geology of Smoke Hollow Area 8 Miles Southeast of Deerlodge, Powell County, Montana

This investigation was undertaken primarily as a problem in geologic mapping. The stratigraphy was studied as to the character, age, and sequence of the geologic formations that are exposed. The conclusions were based principally on the field relationships and lithology because no fossils were found.

Temporal patterns in lacustrine stable isotopes as evidence for climate change during the late glacial in the Southern European Alps

We investigated oxygen and carbon isotopes of bulk carbonate and of benthic freshwater ostracods (Candona candida) in a sediment core of Lago Piccolo di Avigliana that was previously analyzed for pollen and loss-on-ignition, in order to reconstruct environmental changes during the late glacial and early Holocene. The depth-age relationship of the sediment core was established using 14 AMS C-14 dates and the Laacher See Tephra. While stable isotopes of bulk carbonates may have been affected by detrital input and, therefore, only indirectly reflect climatic changes, isotopes measured on ostracod shells provide unambiguous evidence for major environmental changes. Oxygen isotope ratios of ostracod shells (delta O-18(C)) increased by similar to 6 parts per thousand at the onset of the Bolling (similar to 14,650 cal BP) and were similar to 2 parts per thousand lower during the Younger Dryas (similar to 12,850 to 11,650 cal BP), indicating a temporal pattern of climate changes similar to the North Atlantic region. However, in contrast to records in that region, delta O-18(C) gradually decreased during the early Holocene, suggesting that compared to the Younger Dryas more humid conditions occurred and that the lake received gradually increasing input of O-18-depleted groundwater or river water.