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Distribution of Ore Deposits and Spectrographic Analyses of Some Rocks and Ores on the Colorado Plateau

Description: Report discussing an investigation of rocks and ores found on the Colorado Plateau. These studies were conducted in order to determine distribution of elements and the various relationships of ore deposits and igneous rocks.
Date: December 1952
Creator: Riley, Leonard B. & Shoemaker, Eugene N.
Partner: UNT Libraries Government Documents Department

Uranium in Alkaline Rocks

Description: Report describing the results of a literature search, a limited chemical analytical program, and visits to three alkaline-rock localities intended to establish criteria for determining if a site had uranium resource potential. The criteria were applied to various sites in the U.S.; those results are also reported, with additional information about ongoing study.
Date: 1978
Creator: Murphy, Michael A.; Wollenberg, H. A.; Strisower, Beverly; Bowman, H.; Flexser, S. & Carmichael, I.
Partner: UNT Libraries Government Documents Department

The Gabbros and Associated Hornblende Rocks Occurring in the Neighborhood of Baltimore, Maryland

Description: From introduction: The present paper is intended as a contribution to our knowledge of a particular phase of metamorphism in eruptive rocks, i.e., that one which is dependent on the secondary development of hornblende by the paramorphism or pseudomorphism of pyroxene.
Date: 1886
Creator: Williams, George Huntington
Partner: UNT Libraries Government Documents Department

Lead-Alpha Age Determinations of Granitic Rocks from Alaska

Description: Abstract: "Lead-alpha activity age determinations were made on zircon from seven granitic rocks of central and southeastern Alaska. The results of the age determinations indicate two periods of igneous intrusion, one about 95 million years ago, during the Cretaceous period, and another about 53 million years ago, during the early part of the Tertiary. The individual ages determined on zircon from 2 rocks from southeastern Alaska and 1 from east-central Alaska gave results of 90, 100, and 96 million years; those determined on 4 rocks from central Alaska gave results of 47, 56, 58, and 51 million years."
Date: March 1957
Creator: Matzo, J. J.; Jaffe, H. W. & Waring, C. L.
Partner: UNT Libraries Government Documents Department

The Ancient Volcanic Rocks of South Mountain, Pennsylvania

Description: From introduction: In December, 1892, as the result of field work on the part of Dr. G. H. Williams in the northern and of the writer in the southern portion of South Mountain, there appeared a preliminary description of two of the rock types, in which their identification as ancient volcanics was announced. In this bulletin it is proposed to substantiate that identification with more detailed proof. It is further proposed to show that these ancient igneous rocks were, at the time of their consolidation, identical in character with their recent volcanic analogues, and that their present differences are due to subsequent changes, chief among which has been devitrification. It is also proposed to recognize these facts in the nomenclature.
Date: 1896
Creator: Bascom, Florence
Partner: UNT Libraries Government Documents Department

Uranium in Alkaline Rocks: Appendix E. Literature Base

Description: Appendix of literature reviewed for a report on establishing criteria to evaluate the existence of uranium at various sites. Each entry includes the title, author, reference, and descriptors.
Date: 1978
Creator: Murphy, Michael A.; Wollenberg, H. A.; Strisower, Beverly; Bowman, H.; Flexser, S. & Carmichael, I.
Partner: UNT Libraries Government Documents Department

Selected Annotated Bibliography of the Uranium Geology of Igneous and Metamorphic Rocks in the United States and Territories

Description: From introduction: This bibliography is an annotated list of selected reports that were publicly available as of May 31, 1956, pertaining to the uranium content and/or radioactivity of igneous and metamorphic rocks and minerals in the United States.
Date: July 1956
Creator: Curtis, Diane
Partner: UNT Libraries Government Documents Department

Mafic and Ultramafic Xenoliths from Volcanic Rocks of the Western United States

Description: From abstract: Mafic and ultramafic xenoliths in the Western United States are present in volcanic rocks ranging from lamprophyric to dacitic in composition and are found in every major tectonic province from the Coast ranges from California to the Great Plains. Xenoliths from 68 localities are described here, but new localities are being discovered, and much remain to be learned about their distribution with respect to the tectonic and geophysical framework of the Western United States.
Date: 1988
Creator: Wilshire, Howard Gordon; Meyer, C. E.; Nakata, John K.; Calk, L. C.; Shervais, John W.; Nielson, J. E. et al.
Location Info:
Partner: UNT Libraries Government Documents Department

Selected Annotated Bibliography of the Uranium Geology of Igneous and Metamorphic Rocks in the United States and Territories

Description: "This bibliography is an annotated list of selected reports that were publicly available as of May 31, 1956, pertaining to the uranium content and/or radioactivity of igneous and metamorphic rocks and minerals in the United States, Alaska, and Hawaii."
Date: July 1956
Creator: Curtis, Diane
Partner: UNT Libraries Government Documents Department

Some Lava Flows of the Western Slope of the Sierra Nevada, California

Description: From introduction: The field relationships of the rocks described in the following paper were studied during the summers of 1895 and 1896, while I was engaged in geologically mapping portions of the Sonora and Big Trees quadrangles, under the direction of Mr. H. W. Turner.
Date: 1898
Creator: Ransome, Frederick Leslie
Partner: UNT Libraries Government Documents Department

Hydrologic test system for fracture flow studies in crystalline rock

Description: A hydrologic test system has been designed to measure the intrinsic permeabilities of individual fractures in crystalline rock. This system is used to conduct constant pressure-declining flow rate and pressure pulse hydraulic tests. The system is composed of four distinct units: (1) the Packer System, (2) Injection system, (3) Collection System, and (4) Electronic Data Acquisition System. The apparatus is built in modules so it can be easily transported and re-assembled. It is also designed to operate over a wide range of pressures (0 to 300 psig) and flow rates (0.2 to 1.0 gal/min). This system has proved extremely effective and versatile in its use at the Climax Facility, Nevada Test Site.
Date: May 5, 1982
Creator: Raber, E; Lord, D. & Burklund, P.
Partner: UNT Libraries Government Documents Department

Iron isotopic fractionation during continental weathering

Description: The biological activity on continents and the oxygen content of the atmosphere determine the chemical pathways through which Fe is processed at the Earth's surface. Experiments have shown that the relevant chemical pathways fractionate Fe isotopes. Measurements of soils, streams, and deep-sea clay indicate that the {sup 56}Fe/{sup 54}Fe ratio ({delta}{sup 56}Fe relative to igneous rocks) varies from +1{per_thousand} for weathering residues like soils and clays, to -3{per_thousand} for dissolved Fe in streams. These measurements confirm that weathering processes produce substantial fractionation of Fe isotopes in the modern oxidizing Earth surface environment. The results imply that biologically-mediated processes, which preferentially mobilize light Fe isotopes, are critical to Fe chemistry in weathering environments, and that the {delta}{sup 56}Fe of marine dissolved Fe should be variable and negative. Diagenetic reduction of Fe in marine sediments may also be a significant component of the global Fe isotope cycle. Iron isotopes provide a tracer for the influence of biological activity and oxygen in weathering processes through Earth history. Iron isotopic fractionation during weathering may have been smaller or absent in an oxygen-poor environment such as that of the early Precambrian Earth.
Date: October 1, 2003
Creator: Fantle, Matthew S. & DePaolo, Donald J.
Partner: UNT Libraries Government Documents Department

Underground Research Laboratories for Crystalline Rock and Sedimentary Rock in Japan

Description: The Japan Nuclear Cycle Development Institute (JNC) has started two off-site (generic) underground research laboratory (URL) projects, one for crystalline rock as a fractured media and the other for sedimentary rock as a porous media. This paper introduces an overview and current status of these projects.
Date: February 27, 2003
Creator: Shigeta, N.; Takeda, S.; Matsui, H. & Yamasaki, S.
Partner: UNT Libraries Government Documents Department

Geology of the Castle Mountain Mining District, Montana

Description: From preface: This memoir is a general study of the region described, and not a detailed report. The field work upon which it is based formed a part of the work of mapping the areal geology of the Little Belt Mountains sheet of the Geological Survey. The topographic map, made in 1882 by the Northern Transcontinental Survey, is too small in scale and too general in character to warrant more detailed work; but as the facts obtained are of interest, and the region is one of economic importance, it has been considered worthy of a special treatment.
Date: 1896
Creator: Weed, Walter Harvey & Pirsson, Louis Valentine
Partner: UNT Libraries Government Documents Department