Jim Budahn
Jim Budahn is a Scientist Emeritus with the Geosciences and Environmental Change Science Center
Science and Products
Filter Total Items: 61
Geology, geochronology, and geochemistry of basaltic flows of the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra, central New Mexico Geology, geochronology, and geochemistry of basaltic flows of the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra, central New Mexico
The geochronology, geochemistry, and isotopic compositions of basaltic flows erupted from the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra volcanic centres in central New Mexico indicate that each of these lavas had unique origins and that the predominant mantle involved in their production was an ocean-island basalt type. The basalts from Cat Hills (0.11 Ma) and Cat...
Authors
F. Maldonado, J. R. Budahn, L. Peters, D.M. Unruh
Tephra layers of Blind Spring Valley and related upper Pliocene and Pleistocene tephra layers, California, Nevada, and Utah: Isotopic ages, correlation, and magnetostratigraphy Tephra layers of Blind Spring Valley and related upper Pliocene and Pleistocene tephra layers, California, Nevada, and Utah: Isotopic ages, correlation, and magnetostratigraphy
Numerical ages have been determined for a stratigraphic sequence of silicic tephra layers exposed at the Cowan Pumice Mine in Blind Spring Valley, near Benton Hot Springs, east-central California, as well as at Chalk Cliffs, north of Bishop, Calif. The tephra layers at these sites were deposited after eruptions from nearby sources, most of them from near Glass Mountain, and some from...
Authors
Andrei M. Sarna-Wojcicki, Marith C. Reheis, Malcolm S. Pringle, Robert J. Fleck, Doug Burbank, Charles E. Meyer, Janet L. Slate, Elmira Wan, James R. Budahn, Bennie Troxel, James P. Walker
The 2003 phreatomagmatic eruptions of Anatahan volcano - Textural and petrologic features of deposits at an emergent island volcano The 2003 phreatomagmatic eruptions of Anatahan volcano - Textural and petrologic features of deposits at an emergent island volcano
Stratigraphic and field data are used in conjunction with textural and chemical evidence (including data from scanning electron microscope, electron microprobe, X-ray fluorescence, X-ray diffraction, and instrumental neutron activation analysis) to establish that the 2003 eruption of Anatahan volcano was mainly phreatomagmatic, dominated by explosive interaction of homogeneous...
Authors
J.S. Pallister, F. A. Trusdell, I. K. Brownfield, D. F. Siems, J. R. Budahn, S.F. Sutley
Geochemical Analyses of Geologic Materials from Areas of Critical Environmental Concern, Clark and Nye Counties, Nevada Geochemical Analyses of Geologic Materials from Areas of Critical Environmental Concern, Clark and Nye Counties, Nevada
INTRODUCTION An assessment of known and undiscovered mineral resources of selected areas administered by the Bureau of Land Management (BLM) in Clark and Nye Counties, Nevada was conducted by the U.S. Geological Survey (USGS), Nevada Bureau of Mines and Geology (NBMG), and University of Nevada, Las Vegas (UNLV). The purpose of this work was to provide the BLM with information for use in...
Authors
Steve Ludington, Stephen B. Castor, James R. Budahn, Kathryn S. Flynn
Weathering of the meade peak phosphatic shale member, phosphoria formation: Observations based on uranium and its decay products Weathering of the meade peak phosphatic shale member, phosphoria formation: Observations based on uranium and its decay products
Variably weathered outcrop samples of the Meade Peak Phosphatic Shale Member of the Phosphoria Formation have 5-10% of the contained uranium (U) in a form readily extractable by 0.1 M sodium bicarbonate. Fission track radiography of outcrop samples and other less-weathered channel and core samples indicate that this mobile fraction of U is likely hosted by organic matter, secondary iron...
Authors
Robert A. Zielinski, James R. Budahn, Richard I. Grauch, J. B. Paces, K. R. Simmons
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 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...
Authors
A. Iriondo, W. R. Premo, Luis M. Martinez-Torres, J. R. Budahn, William W. Atkinson, D. F. Siems, B. Guaras-Gonzalez
Science and Products
Filter Total Items: 61
Geology, geochronology, and geochemistry of basaltic flows of the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra, central New Mexico Geology, geochronology, and geochemistry of basaltic flows of the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra, central New Mexico
The geochronology, geochemistry, and isotopic compositions of basaltic flows erupted from the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra volcanic centres in central New Mexico indicate that each of these lavas had unique origins and that the predominant mantle involved in their production was an ocean-island basalt type. The basalts from Cat Hills (0.11 Ma) and Cat...
Authors
F. Maldonado, J. R. Budahn, L. Peters, D.M. Unruh
Tephra layers of Blind Spring Valley and related upper Pliocene and Pleistocene tephra layers, California, Nevada, and Utah: Isotopic ages, correlation, and magnetostratigraphy Tephra layers of Blind Spring Valley and related upper Pliocene and Pleistocene tephra layers, California, Nevada, and Utah: Isotopic ages, correlation, and magnetostratigraphy
Numerical ages have been determined for a stratigraphic sequence of silicic tephra layers exposed at the Cowan Pumice Mine in Blind Spring Valley, near Benton Hot Springs, east-central California, as well as at Chalk Cliffs, north of Bishop, Calif. The tephra layers at these sites were deposited after eruptions from nearby sources, most of them from near Glass Mountain, and some from...
Authors
Andrei M. Sarna-Wojcicki, Marith C. Reheis, Malcolm S. Pringle, Robert J. Fleck, Doug Burbank, Charles E. Meyer, Janet L. Slate, Elmira Wan, James R. Budahn, Bennie Troxel, James P. Walker
The 2003 phreatomagmatic eruptions of Anatahan volcano - Textural and petrologic features of deposits at an emergent island volcano The 2003 phreatomagmatic eruptions of Anatahan volcano - Textural and petrologic features of deposits at an emergent island volcano
Stratigraphic and field data are used in conjunction with textural and chemical evidence (including data from scanning electron microscope, electron microprobe, X-ray fluorescence, X-ray diffraction, and instrumental neutron activation analysis) to establish that the 2003 eruption of Anatahan volcano was mainly phreatomagmatic, dominated by explosive interaction of homogeneous...
Authors
J.S. Pallister, F. A. Trusdell, I. K. Brownfield, D. F. Siems, J. R. Budahn, S.F. Sutley
Geochemical Analyses of Geologic Materials from Areas of Critical Environmental Concern, Clark and Nye Counties, Nevada Geochemical Analyses of Geologic Materials from Areas of Critical Environmental Concern, Clark and Nye Counties, Nevada
INTRODUCTION An assessment of known and undiscovered mineral resources of selected areas administered by the Bureau of Land Management (BLM) in Clark and Nye Counties, Nevada was conducted by the U.S. Geological Survey (USGS), Nevada Bureau of Mines and Geology (NBMG), and University of Nevada, Las Vegas (UNLV). The purpose of this work was to provide the BLM with information for use in...
Authors
Steve Ludington, Stephen B. Castor, James R. Budahn, Kathryn S. Flynn
Weathering of the meade peak phosphatic shale member, phosphoria formation: Observations based on uranium and its decay products Weathering of the meade peak phosphatic shale member, phosphoria formation: Observations based on uranium and its decay products
Variably weathered outcrop samples of the Meade Peak Phosphatic Shale Member of the Phosphoria Formation have 5-10% of the contained uranium (U) in a form readily extractable by 0.1 M sodium bicarbonate. Fission track radiography of outcrop samples and other less-weathered channel and core samples indicate that this mobile fraction of U is likely hosted by organic matter, secondary iron...
Authors
Robert A. Zielinski, James R. Budahn, Richard I. Grauch, J. B. Paces, K. R. Simmons
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 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...
Authors
A. Iriondo, W. R. Premo, Luis M. Martinez-Torres, J. R. Budahn, William W. Atkinson, D. F. Siems, B. Guaras-Gonzalez