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George William Moore

Publications and source records attributed to George William Moore.

14 recordsLinked to original sources
USGS1972

Acoustic-reflection profiles, Bay of Campeche: International Decade of Ocean Exploration, U.S. Geological Survey, Leg 1, 1971 cruise, UNITEDGEO I

Introduction As part of a cooperative marine research program designated the International Decade of Ocean Exploration (IDOE), the United States Geological Survey is participating in an investigation of the geologic framework and resource potential of continental margins and small ocean basins in the Gulf of Mexico, Caribbean Sea, and west African continental shelf areas. These studies are funded through the National Science Foundation. Acoustic-reflec­tion profiles of Leg 1, described in this report concern mainly a 200 X 250 kilometer project area in the Bay of Campeche in the southwestern part of the Gulf of Mexico. The cruise leg began at Corpus Christi, Texas, and ended at Veracruz, Mexico. Other geophysical records collected during the cruise include magnetometry, gravimetry, and bathymetry. Visiting scientists from the Institute of Geophysics of the National University of Mexico, the Oceanographic Commission of the Mexican Navy, and the Mexican Institute of Petroleum joined the research vessel UNITEDGEO I throughout the cruise in the Bay of Campeche. The cruise offered an excellent opportunity for scientific interchange between investigators from Mexico and the United States and permitted collaboration in the instru­mentation, operational techniques, and interpretation of acoustic-­reflection records aboard the research vessel.

Bay Of Campeche;Gulf Of Mexico↗
USGS1968

Gold distribution on the sea floor off the Klamath Mountains, California

Analyses of 82 samples collected from the surface of the continental shelf between the Oregon-California border and Eureka, Calif., indicate that the background gold content on this shelf is about 0.1 ppb (part per billion). Four anomalous tracts, which range in extent from 10 to 30 square kilometers, have gold values above 10 ppb, and the richest sample contains 300 ppb. The anomalous areas seem to lack a close correlation with water depth, but they are related to areas underlain by soft Cenozoic strata that contain small quantities of dispersed gold originally derived from lodes in the Klarnath Mountains. This relationship suggests that the offshore gold accumulations are lag concentrates produced from the Cenozoic deposits by wave erosion during the postglacial rise in sea level. Gold contents at the surface are too low for economic recovery, and drilling will be required to determine whether the anomalous areas are underlain by higher grade material.

Circular↗
USGS1960

Origin and chemical composition of evaporite deposits

A comparative study of marine evaporite deposits forming at the present time along the pacific coast of central Mexico and evaporite formations of Permian age in West Texas Basin was made in order to determine if the modern sediments provide a basis for understanding environmental conditions that existed during deposition of the older deposits. The field work was supplemented by investigations of artificial evaporite minerals precipitated in the laboratory and by study of the chemical composition of halite rock of different geologic ages. The environment of deposition of contemporaneous marine salt deposits in Mexico is acidic, is strongly reducing a few centimeters below the surface, and teems with microscopic life. Deposition of salt, unlike that of many other sediments, is not wholly a constructional phenomenon. Permanent deposits result only if a favorable balance exists between deposition in the dry season and dissolution in the wet season. Evaporite formations chosen for special study in the West Texas Basin are, in ascending order, the Castile, Salado, and Rustler formations, which have a combined thickness of 1200 meters. The Castile formation is largely composed of gypsum rock, the Salado, halite rock, and the Rustler, quartz and carbonate sandstone. The lower part of the Castile formation is bituminous and contains limestone laminae. The Castile and Rustler formations thicken to the south at the expense of salt of the intervening Salado formation. The clastic rocks of the Rustler formation are interpreted as the deposits of a series of barrier islands north of which halite rock of the Salado was deposited. The salt is believed to have formed in shallow water of uniform density that was mixed by the wind. Where water depth exceeded the depth of the wind mixing, density stratification developed, and gypsum was deposited. Dense water of high salinity below the density discontinuity was overlain by less dense, more normally saline water which was derived from the sea to the south. Mixing of the two water layers at their interface diluted the lower layer so as to prevent halite formation, but at the same time the depressed solubility of calcium sulfate in the mixture at the interface caused precipitation of gypsum. The upper water layer is believed to have supported a flourishing microscopic biota whose remains descended into semisterile brine below where reducing conditions prevailed. This environment generated the bituminous gypsum rock. At times, microcrystalline calcium carbonate of probable biochemical origin formed in the upper layer and settled below to form limestone laminae such as those of the lower part of the Castile formation. Chemical analyses of Permian and present-day salt were compared with analyses of marine salt as old as Cambrian age to determine if evaporite deposits can contribute information on the geologic history of sea water. The results contain uncertainties that cannot be fully resolved, but they suggest that the ratio between ions in sea water has been approximately constant since Precambrian time. In addition, the abrupt initial appearance of rock salt deposits in Cambrian time suggests that the Precambrian ocean may have been rather dilute, but this apparent relationship also could have been caused by other factors.

Open-File Report↗
USGS1955

Uranium-bearing sandstone in the White River badlands, Pennington County, South Dakota

The uranium mineral uranocircite, a barium uranyl phosphate, occurs in a channel sandstone in the Chadron formation of Oligocene age in the White River badlands, Pennington County, S. Dak. A vertical section of the basal l-foot of the channel contains 0.25 percent uranium. Small amounts of metatyuyamunite (?) occur in the upper part of a freshwater limestone bed in the Chadron formation, and carnotite occurs in chalcedony veins in the overlying Brule formation, also of Oligocene age. The source of the uranium is thought to have been volcanic ash in the Brule formation and the overlying rocks of Miocene age. Downward moving ground water may have leached this uranium and deposited it in the rocks below.

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