Publications
Products (journal articles, reports, fact sheets) authored by current and past scientists are listed below. Please check the USGS Pubs Warehouse for other USGS publications.
Filter Total Items: 1814
40Ar/39Ar ages of late Cenozoic volcanic rocks within and around the Carbondale and Eagle collapse centers, Colorado: Constraints on the timing of evaporite-related collapse and incision of the Colorado River
40Ar/ 39Ar dating results of 133 samples from 84 late Cenozoic volcanic rocks provide emplacement ages that constrain the timing of evaporite collapse and the incision rates of the Colorado River. Our samples are from areas in west-central Colorado, both within and outside of the Carbondale and Eagle collapse centers. Significant pulses of volcanic activity occurred in the intervals from 24 to 22,
Authors
Michael J. Kunk, James R. Budahn, D. M. Unruh, Josette O. Stanley, R. M. Kirkham, Bruce Bryant, R. B. Scott, David J. Lidke, R. K. Streufert
Eagle collapse center: Interpretation of evidence for late Cenozoic evaporite-related deformation in the Eagle River basin, Colorado
Evaporite tectonism resulted in deformation and collapse over an area of ~2500 km2 that is referred to as the Eagle collapse center. The collapse center includes much of the Eagle and Colorado River drainage basins between Vail, Dotsero, and McCoy, Colorado. The volume loss of evaporitic rocks by dissolution in the collapse center is estimated to be nearly 1700 km33 . Before ca. 10 Ma, Miocene bas
Authors
David J. Lidke, Mark R. Hudson, R. B. Scott, Ralph R. Shroba, Michael J. Kunk, W. J. Perry, R. M. Kirkham, James R. Budahn, R. K. Streufert, J.O. Stanley, B.L. Widmann
Two‐step processing for 3D magnetic source locations and structural indices using extended Euler or analytic signal methods
No abstract available.
Authors
Jeffrey Phillips
Late Devonian sea-level changes, catastrophic events, and mass extinctions
Late Devonian history is explained through event stratigraphy comprising a sequence of 18 sea-level changes, catastrophic events, and mass extinctions. Generally rising sea level during the initial Frasnian Stage, beginning with the Taghanic onlap and ending with a sea-level fall and major mass extinction, was interrupted by several exceptionally rapid, very high rises of sea level. These rises ma
Authors
Charles Sandberg, Jared R. Morrow, W. Ziegler
An overview of aggregate resources in the United States
In 2000 the USA produced about 2.7 billion tonnes of aggregate worth about $13.7 billion. Both crushed stone and sand and gravel are produced in virtually every State, although limited quantities are available in the Gulf Coastal Plain, the Colorado Plateau , the Wyoming Basin and the Great Plains. Prices vary depending on the product and location. Most aggregates are transported by road, and mino
Authors
William H. Langer
Planning for the conservation and development of infrastructure resources in urban areas-Colorado front range urban corridor: Things planners, decision-makers, and the public should know
This Circular provides a basic understanding of the characteristics, location, distribution, and quality of infrastructure resources (natural aggregate, energy, and water) in the Colorado Front Range urban corridor between Denver and Ft. Collins. With this understanding, the reader explores the many factors that affect the current and future availability of those resources, including the socioecon
Authors
Belinda F. Arbogast, L. Rick Arnold, Neil S. Fishman, William H. Langer, Carol S. Mladinich, James E. Roelle, David R. Wilburn
Nitrogen in rock: Occurrences and biogeochemical implications
There is a growing interest in the role of bedrock in global nitrogen cycling and potential for increased ecosystem sensitivity to human impacts in terrains with elevated background nitrogen concentrations. Nitrogen-bearing rocks are globally distributed and comprise a potentially large pool of nitrogen in nutrient cycling that is frequently neglected because of a lack of routine analytical method
Authors
J.M. Holloway, R.A. Dahlgren
Subglacial volcanic features beneath the West Antarctic Ice Sheet interpreted from aeromagnetic and radar ice sounding
The West Antarctic Ice Sheet (WAIS) flows through the volcanically active, late Cenozoic West Antarctic rift system. Active subglacial volcanism and a vast (>106 km3) extent of subglacial volcanic structures have been interpreted from aerogeophysical surveys over central West Antarctica in the past decade, combined with results from 1960s and 1970s aeromagnetic profiles over the WAIS. Modelling of
Authors
John C. Behrendt, D. D. Blankenship, D. L. Morse, C. A. Finn, R.E. Bell
Mineral and energy resource assessment of the Gallatin National Forest (exclusive of the Absaroka-Beartooth study area), in Gallatin, Madison, Meagher, Park, and Sweet Grass Counties, south-central Montana
No abstract available.
Authors
Jane M. Hammarstrom, Anna B. Wilson, James E. Elliott, Bradley S. Van Gosen, Robert R. Carlson, Gregory K. Lee, Dolores M. Kulik, John W. M'Gonigle, William J. Perry
Tectonics and distribution of gold deposits in China - An overview
Gold exploration in China has expanded rapidly during the last two decades since a modern approach to economic development has become a national priority. China currently produces 180 tonnes (t) of gold annually, which is still significantly less than South Africa, USA, and Australia. However, China is now recognized as possessing significant gold resources in a wide range of mineral deposit types
Authors
T. Zhou, Richard J. Goldfarb, Neil G. Phillips
Regional fluid flow as a factor in the thermal history of the Illinois basin: Constraints from fluid inclusions and the maturity of Pennsylvanian coals
Vitrinite reflectance measurements on Pennsylvanian coals in the Illinois basin indicate significantly higher thermal maturity than can be explained by present-day burial depths. An interval of additional sedimentary section, now removed by erosion, has been suggested to account for the discrepancy. Although burial could indeed account for the observed maturity levels of organic matter, fluid-incl
Authors
E. L. Rowan, M. B. Goldhaber, J. R. Hatch
Cassini/VIMS observations of the moon
In this paper, we present preliminary scientific results obtained from the analysis of VIMS (Visible and Infrared Mapping Spectrometer) lunar images and spectra. These data were obtained during the Cassini Earth flyby in August 1999. Spectral ratios have been produced in order to derive lunar mineralogical maps. Some spectra observed at the north-east lunar limb, show few unusual absorption featur
Authors
G. Belluci, R. H. Brown, V. Formisano, K. H. Baines, J.-P. Bibring, B. J. Buratti, F. Capaccioni, P. Cerroni, R. N. Clark, A. Coradini, D. P. Cruikshank, P. Drossart, R. Jaumann, Y. Langevin, D. L. Matson, T. B. McCord, V. Mennella, E. Miller, R.M. Nelson, P. D. Nicholson, B. Sicardy, Christophe Sotin