David Ponce (Former Employee)
Science and Products
Filter Total Items: 119
The Mt. Lewis fault zone: Tectonic implications for eastern San Francisco Bay The Mt. Lewis fault zone: Tectonic implications for eastern San Francisco Bay
No abstract available
Authors
Janet Watt, David A. Ponce, Robert W. Simpson, Russell W. Graymer, Robert C. Jachens, Carl M. Wentworth
Anomalously low strength of serpentinite sheared against granite and implications for creep on the Hayward and Calaveras Faults Anomalously low strength of serpentinite sheared against granite and implications for creep on the Hayward and Calaveras Faults
Serpentinized ophiolitic rocks are juxtaposed against quartzofeldspathic rocks at depth across considerable portions of the Hayward and Calaveras Faults. The marked compositional contrast between these rock types may contribute to fault creep that has been observed along these faults. To investigate this possibility, we are conducting hydrothermal shearing experiments to look for changes...
Authors
Diane E. Moore, David A. Lockner, David A. Ponce
Ground-motion modeling of Hayward fault scenario earthquakes, part I: Construction of the suite of scenarios Ground-motion modeling of Hayward fault scenario earthquakes, part I: Construction of the suite of scenarios
We construct kinematic earthquake rupture models for a suite of 39 Mw 6.6-7.2 scenario earthquakes involving the Hayward, Calaveras, and Rodgers Creek faults. We use these rupture models in 3D ground-motion simulations as discussed in Part II (Aagaard et al., 2010) to provide detailed estimates of the shaking for each scenario. We employ both geophysical constraints and empirical...
Authors
Brad T. Aagaard, Robert W. Graves, David P. Schwartz, David A. Ponce, Russell W. Graymer
Geophysical Studies in the Vicinity of the Warner Mountains and Surprise Valley, Northeast California, Northwest Nevada, and Southern Oregon Geophysical Studies in the Vicinity of the Warner Mountains and Surprise Valley, Northeast California, Northwest Nevada, and Southern Oregon
From May 2006 to August 2007, the U.S. Geological Survey (USGS) collected 793 gravity stations, about 102 line-kilometers of truck-towed and ground magnetometer data, and about 325 physical-property measurements in northeastern California, northwestern Nevada, and southern Oregon. Gravity, magnetic, and physical-property data were collected to study regional crustal structures and...
Authors
David A. Ponce, Jonathan M. G. Glen, Anne E. Egger, Claire Bouligand, Janet T. Watt, Robert L. Morin
Physical-Property Measurements on Core samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada Physical-Property Measurements on Core samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada
From May to June 2008, the U.S. Geological Survey (USGS) collected and measured physical properties on 36 core samples from drill-hole Deep Blue No. 1 (DB-1) and 46 samples from drill-hole Deep Blue No. 2 (DB-2) along the west side of Blue Mountain about 40 km west of Winnemucca, Nev. These data were collected as part of an effort to determine the geophysical setting of the Blue Mountain
Authors
David A. Ponce, Janet T. Watt, John Casteel, Grant Logsdon
A prominent geophysical feature along the northern Nevada rift and its geologic implications, north-central Nevada A prominent geophysical feature along the northern Nevada rift and its geologic implications, north-central Nevada
We consider the origin and character of a prominent large-scale geophysical feature in north-central Nevada that is coincident with the western margin of the northern Nevada rift—a mid-Miocene rift that includes mafic dike swarms and associated volcanic rocks expressed by a NNW-striking magnetic anomaly. The geophysical feature also correlates with mid-Miocene epithermal gold deposits...
Authors
David A. Ponce, Jonathan M.G. Glen
Science and Products
Filter Total Items: 119
The Mt. Lewis fault zone: Tectonic implications for eastern San Francisco Bay The Mt. Lewis fault zone: Tectonic implications for eastern San Francisco Bay
No abstract available
Authors
Janet Watt, David A. Ponce, Robert W. Simpson, Russell W. Graymer, Robert C. Jachens, Carl M. Wentworth
Anomalously low strength of serpentinite sheared against granite and implications for creep on the Hayward and Calaveras Faults Anomalously low strength of serpentinite sheared against granite and implications for creep on the Hayward and Calaveras Faults
Serpentinized ophiolitic rocks are juxtaposed against quartzofeldspathic rocks at depth across considerable portions of the Hayward and Calaveras Faults. The marked compositional contrast between these rock types may contribute to fault creep that has been observed along these faults. To investigate this possibility, we are conducting hydrothermal shearing experiments to look for changes...
Authors
Diane E. Moore, David A. Lockner, David A. Ponce
Ground-motion modeling of Hayward fault scenario earthquakes, part I: Construction of the suite of scenarios Ground-motion modeling of Hayward fault scenario earthquakes, part I: Construction of the suite of scenarios
We construct kinematic earthquake rupture models for a suite of 39 Mw 6.6-7.2 scenario earthquakes involving the Hayward, Calaveras, and Rodgers Creek faults. We use these rupture models in 3D ground-motion simulations as discussed in Part II (Aagaard et al., 2010) to provide detailed estimates of the shaking for each scenario. We employ both geophysical constraints and empirical...
Authors
Brad T. Aagaard, Robert W. Graves, David P. Schwartz, David A. Ponce, Russell W. Graymer
Geophysical Studies in the Vicinity of the Warner Mountains and Surprise Valley, Northeast California, Northwest Nevada, and Southern Oregon Geophysical Studies in the Vicinity of the Warner Mountains and Surprise Valley, Northeast California, Northwest Nevada, and Southern Oregon
From May 2006 to August 2007, the U.S. Geological Survey (USGS) collected 793 gravity stations, about 102 line-kilometers of truck-towed and ground magnetometer data, and about 325 physical-property measurements in northeastern California, northwestern Nevada, and southern Oregon. Gravity, magnetic, and physical-property data were collected to study regional crustal structures and...
Authors
David A. Ponce, Jonathan M. G. Glen, Anne E. Egger, Claire Bouligand, Janet T. Watt, Robert L. Morin
Physical-Property Measurements on Core samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada Physical-Property Measurements on Core samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada
From May to June 2008, the U.S. Geological Survey (USGS) collected and measured physical properties on 36 core samples from drill-hole Deep Blue No. 1 (DB-1) and 46 samples from drill-hole Deep Blue No. 2 (DB-2) along the west side of Blue Mountain about 40 km west of Winnemucca, Nev. These data were collected as part of an effort to determine the geophysical setting of the Blue Mountain
Authors
David A. Ponce, Janet T. Watt, John Casteel, Grant Logsdon
A prominent geophysical feature along the northern Nevada rift and its geologic implications, north-central Nevada A prominent geophysical feature along the northern Nevada rift and its geologic implications, north-central Nevada
We consider the origin and character of a prominent large-scale geophysical feature in north-central Nevada that is coincident with the western margin of the northern Nevada rift—a mid-Miocene rift that includes mafic dike swarms and associated volcanic rocks expressed by a NNW-striking magnetic anomaly. The geophysical feature also correlates with mid-Miocene epithermal gold deposits...
Authors
David A. Ponce, Jonathan M.G. Glen
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government