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Publications

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Isotopic, geochemical, and temporal characterization of Proterozoic basement rocks in the Quitovac region, northwestern Sonora, Mexico: Implications for the reconstruction of the southwestern margin of Laurentia

A detailed geochemical characterization of 19 representative Proterozoic basement rocks in the Quitovac region in northwestern Sonora, Mexico, has identified two distinct Paleoproterozoic basement blocks that coincide spatially with the previously proposed Caborca and "North America" blocks. New U-Pb zircon geochronology revises their age ranges, the Caborca (1.78-1.69 Ga) and "North America" (1.7
Authors
A. Iriondo, W. R. Premo, Luis M. Martínez-Torres, J. R. Budahn, William W. Atkinson, D. F. Siems, B. Guaras-Gonzalez

Vital signs monitoring plan for the Klamath Network: Phase I report

This report chronicles the Phase 1 stage of the vital signs monitoring program for the Klamath Network. It consists of two chapters and eleven appendixes. The purposes of Chapter One are to 1) describe the network administrative structure and approach to planning; 2) introduce the Klamath Network parks, their resources, and environmental settings; 3) explain the need for monitoring changes in reso
Authors
Daniel Sarr, Dennis Odion, Robert E. Truitt, Erik A. Beever, Sarah Shafer, Andrew Duff, Sean B. Smith, Windy Bunn, Judy Rocchio, Eli Sarnat, John Alexander, Steve Jessup

Eolian sediments

No abstract available.
Authors
A.J. Busacca, J. E. Beget, H. W. Markewich, D.R. Muhs, N. Lancaster, M.R. Sweeney

Three-dimensional geologic framework modeling of faulted hydrostratigraphic units within the Edwards aquifer, northern Bexar County, Texas

This report includes a digital, three-dimensional (3-D) faulted hydrostratigraphic model we have constructed to represent the geologic framework of the Edwards aquifer system in the area of San Antonio, northern Bexar County, Texas. The model is based on mapped geologic relationships that reflect the complex structures of the Balcones fault zone, detailed lithologic descriptions and interpretation
Authors
Michael P. Pantea, J. C. Cole

Geochemistry of dust in the Exploratory Studies Facility, Yucca Mountain, Nevada

No abstract available.
Authors
Zell E. Peterman, James B. Paces, Leonid A. Neymark, D. Hudson

Summary of Chlorine-36 validation studies at Yucca Mountain, Nevada

No abstract available.
Authors
James B. Paces, Zell E. Peterman, Leonid A. Neymark, G. J. Nimz, M. Gascoyne, Brian D. Marshall

Reliability of U-Th-Pb dating of secondary silica at Yucca Mountain, Nevada

No abstract available.
Authors
Leonid A. Neymark, James B. Paces, Y. V. Amelin

The Rocky Mountain glacial model; the Wind River Range, Wyoming

No abstract available.
Authors
D. E. Dahms, R. D. Hall, Ralph R. Shroba, C. J. Sorenson, E. A. Lynch, M. T. Applegarth

Quaternary vegetation and climate change in the western United States: Developments, perspectives, and prospects

This chapter explores the strengths and shortcomings of the major sources of data on Quaternary vegetation and climate change and discusses the use of models as a means to explore past and potential future environmental changes. The flora and major vegetation types of the western United States are present for several million years. Ongoing changes in atmospheric chemistry, climate, and human activ
Authors
Robert S. Thompson, Sarah Shafer, Laura E. Strickland, Peter K. Van De Water, Katherine H. Anderson