From introduction: The results of U. S. Geological Survey exploration in the Legin group area are summarized briefly in this preliminary report. No additional drilling is planned. The Legin group area comprising nine Government-owned claims, three privately owned claims and adjoining public land, is in San Miguel County, Colo. The area explored includes parts of secs. 28 and 29, T. 43 N., R. 19 W., New Mexico principal meridian (fig. 1).

A report pertaining to an exploration by the U.S. Geologic Survey in the southern part of the Uravan district for uranium-vanadium deposits. The explored area is in Montrose County, Colorado. The rocks exposed in the area are gently dripping marine and terrestial formations ranging in age from late Paleozoic to late Mesozoic.

"Between April 21, 1949, and August 20, 1955, the U.S. Geological Survey explored the southern part of the Uravan district for uranium-vanadium deposits and to appraise the uranium-vanadium reserves in the area."

Report discussing the the development of milling practice in Boulder County, the ore-dressing methods in use, and the local manufacture of ferrotungsten and tungstic oxide. Figures giving the production of tungsten concentrates in the Boulder district, in the United States, and in the world; data on the buying of tungsten ores; costs of production; and the normal tungsten requirements in this country are presented.

A report about the vanadium-uranium deposit at the Rifle and Garfield mines which lies in the Wingate sandstone and the overlying Entrada sandstone.

Report issued by the U.S. Bureau of Mines describing the methods and equipment developed at the oil-shale mine near Rifle, Colorado. This report includes photographs and illustrations documenting this equipment.

A report regarding Preliminary reserve statement 18, reserve block 6, Club Mesa, Montrose County, Colorado

The objectives of the study were: to evaluate the response of grassland ecosystems to atmospheric change at regional and site scales, and to develop multiscaled modeling systems to relate ecological and atmospheric models with different spatial and temporal resolutions. A menu-driven shell was developed to facilitate use of models at different temporal scales and to facilitate exchange information between models at different temporal scales. A detailed ecosystem model predicted that C{sub 3} temperate grasslands wig respond more strongly to elevated CO{sub 2} than temperate C{sub 4} grasslands in the short-term while a large positive N-PP response was predicted for a C{sub 4} Kenyan grassland. Long-term climate change scenarios produced either decreases or increases in Colorado plant productivity (NPP) depending on rainfall, but uniform increases in N-PP were predicted in Kenya. Elevated CO{sub 2} is likely to have little effect on ecosystem carbon storage in Colorado while it will increase carbon storage in Kenya. A synoptic climate classification processor (SCP) was developed to evaluate results of GCM climate sensitivity experiments. Roughly 80% agreement was achieved with manual classifications. Comparison of lx and 2xCO{sub 2} GCM Simulations revealed relatively small differences.

This report follows a preliminary geophysical investigation that was made in the Colorado-Utah Plateau in search of carnotite ore deposits.

The environmental transport pathway of soil-borne radioisotopes to vegetation surfaces via raindrop splash was studied. The data show that soil can significantly contribute to the contamination found on plants. Further detailed study is needed to calculate the rate constant for the raindrop splash and retention pathways. 8 references, 1 figure. (ACR)

Report summarizing the study of carnotite-bearing sandstone deposits in the Colorado Plateau.

From introduction: The general distribution of known deposits of vanadium-bearing sandstone, which also contain some uranium and radium, is shown in figure 1 1/ and Exhibit A, plate 53. 2/ During 1939-41 the Geological Survey made detailed geological studies of these deposits in the Uravan district, Montrose County, Colorado, as well as preliminary examinations in other parts of the Colorado Plateau vanadium region. In 1942 detailed geological studies were made o the deposits in the Egnar-Slick Rock district, San Miguel Co., Colo.; 3/ the Carrizo Moungains district, Navajo Indian Reservation, Arizona and New Mexico; 4/ the Placerville district, San Miguel County, Colo. 5/ and the Monticello district, San Juan Co., Utah. 6/ Since May 3, 1943, the Gelogical Survey has guided the Bureau of Mines program of prospecting these deposits in parts of Colorado and Utah.

An interim report regarding diamond drill exploration and plans for additional drilling in the Monogram Mesa Area, Montrose County, Colorado.

Five structure maps showing favorable areas for vein uranium deposits Badger Flats - Elkhorn Thrust project area created for a geologic and geochemical study of the Precambrian igneous and metamorohic rock zones in the project area.

This report follows the geologic and geochemical study of the Precambrian igneous and metamorohic rock zones in Badger Flats - Elkhorn Thrust area of Park and Teller counties, Colorado.

Report outlining development drilling in the Hawkeye Claim Area Slick Rock District, San Miguel County, Colorado, including the geology, ownership, location, and plans for future drilling. Maps of the development drilling area and a summary of assay data, in tabulated form, are also included.

A report regarding development drilling in the Hawkeye claim area, Slick Rock District, San Miguel County, Colorado

From abstract: "This study used Landsat images and small-scale color and color-infrared photographs for selected geologic, hydrologic, and land-use applications within the Yampa River Basin" in Colorado and Wyoming. It includes maps, tables, and a glossary.

The attached reports and proposal summarize the work to date for the revised Ultrasonic Resonance Interferometry system. The most recent set of experiments, to determine the accuracy of the implementation of a new calibration curve to account for the variation of the wave speed with temperature, were never completed due to lack of funding. The general focus of the ongoing work, outlined in the weekly reports, had been improvements in accuracy of the measurement system using software modifications. The future focus of the project, as outlined in the attached proposal, was to incorporate a thermal conductivity probe with the ultrasonic measurement system to allow measurement of fluids which have a bimodal wavespeed vs. molarity relation.

A report regarding regional fracture systems mapped for an area of about 90,000 square miles, embracing most of the Colorado Plateau and small strips of the adjoining Rocky Mountains, by the use of aerial photographs and mosaics. The data interpreted from the photographically reduced to produce the final map.

Report and supporting maps on the West Paradox District

From introduction: The purpose of this work was to determine the distribution and reserves of pitchblende in the veins. These particular mines were selected because the other mines that had produced pitchblende in the east were either inaccessible, or accessible under such adverse conditions as to make detailed mapping impracticable.

From introduction: This report describes work done in the Trinidad, Colorado, National Topographic Map Series (NTMS) quadrangle (US Geological Survey, 1955) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

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