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Geology topics

Richard Philip Fischer

Publications and source records attributed to Richard Philip Fischer.

16 recordsLinked to original sources
USGS1968

Interpreting pan-concentrate analysis of stream sediments in geochemical exploration for gold

A study of methods of collecting and processing samples to determine whether or not gold is present in areas of moderate size was undertaken in the northwestern part of the San Juan Mountains, Colo. As part of this study, 57 samples of pan concentrates were taken from streams draining three types of areas: (1)'barren' areas, where gold mineralization might be geologically possible but no deposits are known, (2) slightly mineralized areas that contain only a few known veins and prospects and small mines, and (3) well-mineralized areas that contain numerous veins and some very productive mines. The concentrate samples were analyzed by the fire-assay-atomic-absorption method. Replicate analyses of large samples gave results consistent enough to permit placing considerable confidence in the results obtained for smaller samples on which only one analysis was made. For general field practice, it is necessary to pan only enough sand and gravel to yield about 15 grams of concentrate. The analytical r6sults are also quantitatively compatible with known geologic relations and indicate that a few samples from a stream are adequate to distinguish between 'barren' and mineralized areas and to determine the relative amount of gold in mineralized areas. In other areas of similar gold deposits, data of this type should help decide whether more intensive search for gold deposits is justified.

Circular↗
USGS1962

Vanadium in the United States, exclusive of Alaska and Hawaii

The productive and potential raw material sources of vanadium in the United States (exclusive of Alaska and Hawaii) are shown on the accompanying map. This map is at the scale of 50 miles to the inch. The text accompanying the map briefly describes the major geologic types of deposits of vanadium, and it lists the productive and potential sources by the name of the deposit or geographic area and by coordinates to the nearest minute of latitude and longitude. Each productive or potential source is listed by state and a number, and its location on the map is identified by the same number. The text and the map were compiled from published and unpublished information; at least one reference is given for each locality if reports on it have been published.

Mineral Investigations Resource Map↗
USGS1950

Uranium-bearing sandstone deposits of the Colorado Plateau

The uranium-bearing sandstone deposits of the Colorado Plateau are commonly referred to as "carnotite deposits." They have been the principal domestic source of uranium, radium, and vanadium. The deposits are largely restricted to a few stratigraphic zones, along which they have a wide but spotty areal distribution. The ore minerals mainly impregnate sandstone, though in places fossil plants are richly mineralized. Most of the ore bodies are small, but have a wide range in size, and within individual deposits the ore has a considerable range in thickness and grade. The deposits are irregularly tabular or lenticular, with their long axes nearly parallel to the bedding, but the ore does not follow the beds in detail.The ore is thought to have been precipitated from ground-water solutions after the enclosing sands had accumulated and before regional deformation. Sedimentary structures that seem to have controlled the movement of these solutions and the features that probably localized the ore deposits are described, and their application as guides to ore finding is explained.

Colorado, Utah, Wyoming↗