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
Gravity and magnetic studies of the eastern Mojave Desert, California and Nevada
IntroductionFrom May 2011 to August 2014, the U.S. Geological Survey (USGS) collected gravity data at more than 2,300 stations and physical property measurements on more than 640 rock samples from outcrops in the eastern Mojave Desert, California and Nevada. Gravity, magnetic, and physical-property data are used to study and locate regional...
Denton, Kevin M.; Ponce, David A.
Imaging the magmatic system of Mono Basin, California with magnetotellurics in three--dimensions
A three–dimensional (3D) electrical resistivity model of Mono Basin in eastern California unveils a complex subsurface filled with zones of partial melt, fluid–filled fracture networks, cold plutons, and regional faults. In 2013, 62 broadband magnetotelluric (MT) stations were collected in an array around southeastern Mono Basin from...
Peacock, Jared R.; Mangan, Margaret T.; McPhee, Darcy; Ponce, David A. A summary of the late Cenozoic stratigraphic and tectonic history of the Santa Clara Valley, California
The late Cenozoic stratigraphic and tectonic history of the Santa Clara Valley illustrates the dynamic nature of the North American–Pacific plate boundary and its effect on basin and landscape development. Prior to early Miocene time, the area that became Santa Clara Valley consisted of eroding Franciscan complex basement structurally interleaved...
Langenheim, Victoria E.; Jachens, Robert C.; Wentworth, Carl M.; Graymer, Russell W.; Stanley, Richard G.; McLaughlin, Robert J.; Simpson, Robert W.; Williams, Robert A.; Andersen, D. W.; Ponce, David A. Structural superposition in fault systems bounding Santa Clara Valley, California
Santa Clara Valley is bounded on the southwest and northeast by active strike-slip and reverse-oblique faults of the San Andreas fault system. On both sides of the valley, these faults are superposed on older normal and/or right-lateral normal oblique faults. The older faults comprised early components of the San Andreas fault system as it formed...
Graymer, Russell W.; Stanley, Richard G.; Ponce, David A.; Jachens, Robert C.; Simpson, Robert W.; Wentworth, Carl M. 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. John Geophysical 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.