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Terminology for Stratification and Cross-Stratification in Sedimentary Rock

Description: From abstract: "A terminology is suggested for stratified and cross-stratified rock units that will aid the field geologist in describing these structures... A classification of cross-stratification based primarily on the character of the lower bounding surface of a set of cross-strata is suggested."
Date: September 1952
Creator: Mckee, Edwin D. & Weir, Gordon W.
Partner: UNT Libraries Government Documents Department

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

Conditions of the Formation of Fluorite in Sedimentary Rocks (The Fluorite System)

Description: From translator's abstract: "The formation of fluorite in sedimentary rocks has been investigated by studies of fluorite equilibria in different solutions. Determinations at different temperatures were made on the solubility of crystalline CaF2 in chemically pure water, in aqueous solutions of components of seat water...at different concentrations, and in the sea water itself at degrees of salinity varying from normal to a 15-fold concentration."
Date: April 1951
Creator: Kazakov, A. V. & Sokolova, E. I.
Partner: UNT Libraries Government Documents Department

The Fluorapatite System of Equilibria in the Conditions of Formation of Sedimentary Rocks

Description: From translator's abstract: "As part of unified research on the behavior of the fluoride ion in sedimentary rocks, the present study deals with the system CaO-P2O5-HF-H20 at 25 degrees C. under conditions of sea sedimentation. The precipitated phases, their fields of crystallization and stability, the fluorine-phosphorus coefficient, and the isomorphism of fluorhydroxl ions in the apatite lattice are considered and illustrated by orthogonal projections."
Date: April 1951
Creator: Kazakov, A. V.
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

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

Progress Report on Geologic Studies in the Capitol Reef Area, Wayne County, Utah

Description: From abstract: During 1951 about 60 square miles of the Capitol Reef area, Wayne County, Utah, the northern end of the Waterpocket Fold, was mapped by plane-table methods on a scale of 1:62, 500. Formations, with an approximate aggregate thickness of 3, 200 feet, range from the Coconino sandstone of Permian age to the Navajo sandstone of Jurassic (?) age. About 35 linear miles of Shinarump conglomerate of Triassic age was examined in detail. Cliffs 900 to 1, 000 feet high form the west face of Capitol Reef, which is on the east and northeast flanks of a structural and topographic dome, The uranium deposits are in the basal part of the Shinarump conglomerate. Zippeite and metatorbernite are the uranium minerals found, and are associated with copper minerals, carbonaceous matter, clay beds, a thick bleached zone at the top of the Moenkopi formation, and channels or scours in the top of the Moenkopi. The highest radioactivity is in a clay bed at the base of the Shinarump conglomerate, and was detected at 7 localities between Grand Wash and Capitol Gorge, at the Birch Spring prospect in Moonie Draw, and at the Oyler mine in Grand Wash.
Date: August 1952
Creator: Smith, J. Fred, Jr.; Hinrichs, E. Neal & Luedke, Robert G.
Partner: UNT Libraries Government Documents Department

Geological Study of Uranium Potential of the Kingston Peak Formation, Death Valley Region, California: Final Report

Description: From introduction: Our particular interest in the uranium potential of the Proterozoic quartz-pebble and quartzite-pebble conglomerates of the Kingston Peak Formation has been based upon: 1. Known uranium occurrences of low to intermediate grade in a peliticarkosic sulfide-bearing unit near the base of the formation; the "Favorable Submember" of this report. 2. Uranium occurrences and widespread anomalies in underlying Proterozoic granitic-metamorphic rocks, including the World Beater Complex, within and bordering the basin in which the conglomerates were deposited. 3. Reported minor shows of uranium associated with extensive anomalous radioactivity in the conglomerates themselves.
Date: September 1980
Creator: Carlisle, Donald; Kettler, Richard M. & Swanson, Steven C.
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

Research on the physical properties of geothermal reservoir rock. Annual report, September 1, 1977

Description: Measurements have been made of the electrical resistivity, the acoustic wave speed, density, and water content of six groups of rock samples taken from Cenozoic volcanic units. It has been found from these measurements that the correlations between physical properties are significantly different in the case of volcanic rocks than in the case of sandstones and limestones. For a given porosity and water content, the resistivity of a volcanic rock is several fold greater than that of a sandstone or limestone. Also, there is a weaker correlation between acoustic wave speed and porosity in volcanic rocks than in sandstones and limestones. The effect of temperature on the properties of these rocks appears to be predictable from fundamental considerations to temperatures as high as 100/sup 0/C.
Date: September 25, 1977
Creator: Keller, G.V.; Grose, L.T. & Pickett, G.R.
Partner: UNT Libraries Government Documents Department

A comparative simulation study of coupled THM processes and their effect on fractured rock permeability around nuclear waste repositories

Description: This paper presents an international, multiple-code, simulation study of coupled thermal, hydrological, and mechanical (THM) processes and their effect on permeability and fluid flow in fractured rock around heated underground nuclear waste emplacement drifts. Simulations were conducted considering two types of repository settings: (a) open emplacement drifts in relatively shallow unsaturated volcanic rock, and (b) backfilled emplacement drifts in deeper saturated crystalline rock. The results showed that for the two assumed repository settings, the dominant mechanism of changes in rock permeability was thermal-mechanically-induced closure (reduced aperture) of vertical fractures, caused by thermal stress resulting from repository-wide heating of the rock mass. The magnitude of thermal-mechanically-induced changes in permeability was more substantial in the case of an emplacement drift located in a relatively shallow, low-stress environment where the rock is more compliant, allowing more substantial fracture closure during thermal stressing. However, in both of the assumed repository settings in this study, the thermal-mechanically-induced changes in permeability caused relatively small changes in the flow field, with most changes occurring in the vicinity of the emplacement drifts.
Date: October 23, 2008
Creator: Rutqvist, Jonny; Barr, Deborah; Birkholzer, Jens T.; Fujisaki, Kiyoshi; Kolditz, Olf; Liu, Quan-Shen et al.
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

Origin of a sanidine-coesite grospydite

Description: A grospydite xenolith from the Roberts Victor kimberlite pipe in South Africa presents an unusual phase assemblage of clinopyroxene, garnet, kyanite, coesite, and sanidine. The rock as previously described (Smyth and Hatton, 1977) consists of 50% omphocitic clinopyroxene, 28% garnet (Gr/sub 50/Py/sub 28/Alm/sub 22/), 9% kyanite, 65 coesite, and 1% sanidine (Or/sub 99/). Assuming the addition of three additional compatible phases (phlogopite, enstatite, and H/sub 2/O vapor) and a simplified chemistry of the phases present, a Schreinemakers thermodynamic analysis was attempted in order to estimate the pressure and temperature of equilibrium of the rock. Four reactions involving six components are likely to have determined an invariant point for the assemblage: (1) Kyn + 2 Cpx reversible Cos + Gt + En; (2) 3 Cos + Phl reversible San + 3 En + H/sub 2/O; (3) 3 Kyn + 6 Cpx + Phl reversible San + 3 Gt + 6 En + H/sub 2/O; and (4) 6 Cos + 3 gt + Phl reversible San + 3 Kyn + 6 Cpx + H/sub 2/O. Using tabulated as well as estimated thermodynamic data for the phases, the calculated values for equilibrium temperatures and pressures for the reactions yield an invariant point for the assemblage at a depth of about 160 km (40 kbars) and a temperature of about 1060/sup 0/C. This point likely represents a subsolidus recrystallization stage of origin.
Date: January 1, 1982
Creator: Wohletz, K.H. & Smyth, J.R.
Partner: UNT Libraries Government Documents Department

GENERIC THERMO-MECHANICAL MODEL FOR JOINTED ROCK MASSES

Description: A new nonlinear thermo-mechanical model for heavily jointed rock masses is presented. The model uses correlation functions between the porosity and the basic rock properties such as elastic moduli, tensile and compressive strength. The model assumes that the media is isotropic and is characterized by two variable parameters: insipient porosity and in-situ-to-intact modulus ratio.
Date: March 8, 2007
Creator: Vorobiev, O
Partner: UNT Libraries Government Documents Department