David Ponce
Dave Ponce is a Research Geophysicist with the Geology, Minerals, Energy, and Geophysics Science Center in Menlo Park, California. His work focuses on the application of gravity, magnetic, and other geophysical methods to address a variety of earth science issues including earthquake hazards and mineral resources.
Biography
David Ponce is a senior Research Geophysicist with the U.S. Geological Survey (USGS) in Menlo Park, California, with over 30 years of experience. He is a member and past Chief of the Geophysical Unit of Menlo Park (GUMP), a potential-field (gravity and magnetics), paleomagnetic, and electromagnetic methods research group. He received a B.S. and M.S. in Geology/Geophysics from San Jose State University, California. His primary areas of interest are geophysical investigations of the San Francisco Bay Area and the Basin and Range Province of the western U.S. These studies utilize geophysical methods to understand geology and tectonophysics; volcano and earthquake hazards; and water, mineral, and energy resources. He has authored more than 250 abstracts, reports, maps, or articles.
Dave is also a member of the American Geophysical Union, Geological Society of America, and Society of Exploration Geophysicists and is a recipient of the Superior Service Award from the Department of Interior.
Professional Experience:
- Research Geophysicist, Geophysics Unit of Menlo Park (GUMP), Geology, Minerals, Energy and Geophysics Science Center (GMEG)
- Project Chief, REE deposits in the southeast Mojave Desert, California
- Principal Investigator, Geophysical investigations of the Calaveras, Hayward, and Rodgers Creek Faults, California and implications on earthquake hazards.
Education:
- B.S., Geophysics/Geology, San Jose State University, 1976
- M.S., Geophysics/Geology, San Jose State University, 1981
Affiliations:
- American Geophysical Union
- Geological Society of America
- Society of Exploration Geophysicists
Science and Products
Subsurface geometry of the San Andreas-Calaveras fault junction: influence of serpentinite and the Coast Range Ophiolite
While an enormous amount of research has been focused on trying to understand the geologic history and neotectonics of the San Andreas-Calaveras fault (SAF-CF) junction, fundamental questions concerning fault geometry and mechanisms for slip transfer through the junction remain. We use potential-field, geologic, geodetic, and seismicity data to...
Watt, Janet Tilden; Ponce, David A.; Graymer, Russell W.; Jachens, Robert C.; Simpson, Robert W.Magnetic and gravity studies of Mono Lake, east-central, California
From August 26 to September 5, 2011, the U.S. Geological Survey (USGS) collected more than 600 line-kilometers of shipborne magnetic data on Mono Lake, 20 line-kilometers of ground magnetic data on Paoha Island, 50 gravity stations on Paoha and Negit Islands, and 28 rock samples on Paoha and Negit Islands, in east-central California. Magnetic and...
Athens, Noah D.; Ponce, David A.; Jayko, Angela S.; Miller, Matt; McEvoy, Bobby; Marcaida, Mae; Mangan, Margaret T.; Wilkinson, Stuart K.; McClain, James S.; Chuchel, Bruce A.; Denton, Kevin M.Regional geophysical expression of a carbonatite terrane in the eastern Mojave Desert, California
A world-class, rare earth element carbonatite deposit is located near Mountain Pass, in the eastern Mojave Desert of California and is hosted by Proterozoic rocks that extend along the eastern margins of the Clark Mountain Range, Mescal Range, and Ivanpah Mountains in a north-northwest trending fault-bounded block. This Proterozoic block is...
Ponce, David A.; Denton, Kevin M.; Miller, David M.Geophysical studies in the vicinity of Blue Mountain and Pumpernickel Valley near Winnemucca, north-central Nevada
From May 2008 to September 2009, the U.S. Geological Survey (USGS) collected data from more than 660 gravity stations, 100 line-km of truck-towed magnetometer traverses, and 260 physical-property sites in the vicinity of Blue Mountain and Pumpernickel Valley, northern Nevada (fig. 1). Gravity, magnetic, and physical-property data were collected to...
Ponce, David A.Long‐term creep rates on the Hayward Fault: evidence for controls on the size and frequency of large earthquakes
The Hayward fault (HF) in California exhibits large (Mw 6.5–7.1) earthquakes with short recurrence times (161±65 yr), probably kept short by a 26%–78% aseismic release rate (including postseismic). Its interseismic release rate varies locally over time, as we infer from many decades of surface creep data. Earliest estimates of...
Lienkaemper, James J.; McFarland, Forrest S.; Simpson, Robert W.; Bilham, Roger; Ponce, David A.; Boatwright, John; Caskey, S. JohnGeophysical setting of the February 21, 2008 Mw 6 Wells earthquake, Nevada, and implications for earthquake hazards
We utilize gravity and magnetic methods to investigate the regional geophysical setting of the Wells earthquake. In particular, we delineate major crustal structures that may have played a role in the location of the earthquake and discuss the geometry of a nearby sedimentary basin that may have contributed to observed ground shaking. The February...
Ponce, David A.; Watt, Janet T.; Bouligand, C.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...
Moore, Diane E.; Lockner, David A.; Ponce, David A.The Mt. Lewis fault zone: Tectonic implications for eastern San Francisco Bay
No abstract available
Watt, Janet; Ponce, David A.; Simpson, Robert W.; Graymer, Russell W.; Jachens, Robert C.; Wentworth, Carl M.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...
Aagaard, Brad T.; Graves, Robert W.; Schwartz, David P.; Ponce, David A.; Graymer, Russell W.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...
Ponce, David A.; Glen, Jonathan M.G.; Egger, Anne E.; Bouligand, Claire; Watt, Janet T.; Morin, Robert L.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...
Ponce, David A.; Watt, Janet T.; Casteel, John; Logsdon, GrantStructures controlling geothermal circulation identified through gravity and magnetic transects, Surprise Valley, California, northwestern Great Basin
No abstract available.
Glen, Jonathan M.G.; Egger, Anne E.; Ponce, David A.