Publications
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Relationship between porphyry systems, crustal preservation levels, and amount of exploration in magmatic belts of the Central Tethys Region
Tectonic, geologic, geochemical, geochronologic, and ore deposit data from the U.S. Geological Survey-led assessment of 26 porphyry belts identified in the central Tethys region of Turkey, the Caucasus, Iran, western Pakistan, and southern Afghanistan relate porphyry mineralization to the tectonomagmatic evolution of the region and associated subduction and postsubduction processes. However, uplif
Authors
Lukas Zürcher, Jane M. Hammarstrom, John C. Mars, Stephen Ludington, Michael L. Zientek
Select airborne techniques for mapping and problem solving: Chapter 30
No abstract available.
Authors
Andrea Donnellan, Ramon Arrowsmith, Victoria E. Langenheim
Regional and local correlations of feldspar geochemistry of the Peach Spring Tuff, Alvord Mountain, California
The chemical composition of feldspar grains in an ignimbrite from the Spanish Canyon Formation in the Alvord Mountain area, California, have been used to confirm similarities in three measured sections locally, and they are similar to exposures of the Peach Spring Tuff (PST) regionally. Feldspar grains were identified on the basis of texture (zoning, as mantled feldspars, or in crystal clusters),
Authors
David C. Buesch
Cumberland-Marlboro basin basement drilling results – 2015: Cumberland, Hoke and Scotland counties, North Carolina
No abstract available
Authors
Jeffrey C. Reid, James L. Coleman, Kenneth B. Taylor, Katherine J. Marciniak, Walter T. Haven, Ryan A. Channell, Chandler I. Warner
Analysis and interpretation of stress indicators in deviated wells of the Coso Geothermal Field
Characterizing the tectonic stress field is an integral part of the development of hydrothermal systems and especially for enhanced geothermal systems (EGS). With a well characterized stress field the propensity of fault slip on faults with known location and orientation can be identified. Faults that are critically oriented for faulting with respect to the stress field are known to provide natura
Authors
Martin Schoenball, Jonathan M. G. Glen, Nicholas C. Davatzes
A strategy for low cost development of incremental oil in legacy reservoirs
The precipitous decline in oil prices during 2015 has forced operators to search for ways to develop low-cost and low-risk oil reserves. This study examines strategies to low cost development of legacy reservoirs, particularly those which have already implemented a carbon dioxide enhanced oil recovery (CO2 EOR) program. Initially the study examines the occurrence and nature of the distribution of
Authors
E. D. Attanasi
By-products of porphyry copper and molybdenum deposits
Porphyry Cu and porphyry Mo deposits are large to giant deposits ranging up to >20 and 1.6 Gt of ore, respectively, that supply about 60 and 95% of the world’s copper and molybdenum, as well as significant amounts of gold and silver. These deposits form from hydrothermal systems that affect 10s to >100 km3 of the upper crust and result in enormous mass redistribution and potential concentration of
Authors
David John, Ryan D. Taylor
Paleoclimate and the origin of Paleozoic chert: Time to re-examine the origins of chert in the rock record
No abstract available.
Authors
C. Blaine Cecil
Geologic framework for the assessment of undiscovered oil and gas resources in sandstone reservoirs of the Upper Jurassic-Lower Cretaceous Cotton Valley Group, U.S. Gulf of Mexico region
The U.S. Geological Survey (USGS) is assessing the undiscovered oil and gas resources in sandstone reservoirs of the Upper Jurassic–Lower Cretaceous Cotton Valley Group in onshore areas and State waters of the U.S. Gulf of Mexico region. The assessment is based on geologic elements of a total petroleum system. Four assessment units (AUs) are defined based on characterization of hydrocarbon source
Authors
Jennifer D. Eoff, Russell F. Dubiel, Ofori N. Pearson, Katherine J. Whidden
Underpressure in Mesozoic and Paleozoic rock units in the Midcontinent of the United States
Potentiometric surfaces for Paleozoic strata, based on water well levels and selected drill-stem tests, reveal the control on hydraulic head exerted by outcrops in eastern Kansas and Oklahoma. From outcrop in the east, the westward climb of hydraulic head is much less than that of the land surface, with heads falling so far below land surface that the pressure:depth ratio in eastern Colorado is le
Authors
Philip H. Nelson, Nicholas J. Gianoutsos, Ronald Drake
Geologic maps of the eastern Alaska Range, Alaska (1:63,360 scale)
This report provides a description of map units for a suite of 44 inch-to-mile (1:63,360-scale) geologic quadrangle maps of the eastern Alaska Range. This report also contains a geologic and tectonic summary and a comprehensive list of references pertaining to geologic mapping and specialized studies of the region. In addition to the geologic maps of the eastern Alaska Range, this package includes
Authors
Warren J. Nokleberg, John N. Aleinikoff, Gerard C. Bond, Oscar J. Ferrians, Paige L. Herzon, Ian M. Lange, Ronny T. Miyaoka, Donald H. Richter, Carl E. Schwab, Steven R. Silva, Thomas E. Smith, Richard E. Zehner
The U.S. Geological Survey coal quality (COALQUAL) database version 3.0
Since the mid-1970s, the U.S. Geological Survey (USGS) has maintained a coal quality database of national scope named USCHEM, which currently contains data for over 13,000 samples. A subset of the USCHEM database called COALQUAL Version 1.3 was initially published in 1994 and was followed by Version 2.0 in 1997. Version 3.0 of the COALQUAL database represents a major editing effort to resolve some
Authors
Curtis A. Palmer, Charles L. Oman, Andy J. Park, James A. Luppens