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.
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 and Certifications
M.S., Geophysics/Geology, San Jose State University, 1981
B.S., Geophysics/Geology, San Jose State University, 1976
Affiliations and Memberships*
American Geophysical Union
Geological Society of America
Society of Exploration Geophysicists
Science and Products
Rare Earth Element Deposits in the Southeast Mojave Desert
Gravity Data in the eastern Mojave Desert, California and Nevada
Density and Magnetic Properties of Selected Rock Samples from the Western U.S. and Alaska
High-Resolution Airborne Gravity Gradiometry, Magnetic, and Radiometric Data of Mountain Pass, Southeast Mojave Desert, California
High-Resolution Airborne Radiometric Survey of Mountain Pass, California
Density and magnetic properties of selected plutons (granitoids) in the Great Basin, parts of California, Nevada, Oregon, Utah, and Arizona
High-Resolution Aeromagnetic Survey of Mono Basin and Long Valley, California
Whole Rock Density, Magnetic Susceptibility, and Radiometric Measurements of a Rare Earth Element Terrane, Southeastern Mojave Desert.
Airborne magnetic and radiometric survey of the southeast Mojave Desert, California and Nevada
Magnetotelluric data from San Pablo Bay, California
GIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements
High-Resolution Aeromagnetic Survey of Mountain Pass, California
Depth to pre-Cenozoic bedrock in northern Nevada
Airborne radiometric maps of Mountain Pass, California
Geophysical investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area encompasses Mountain Pass, host to one of the world’s largest rare earth element carbonatite deposits. The deposit is found along a north-northwest-trending,
Aeromagnetic map of Mountain Pass and vicinity, California and Nevada
Magnetic investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain Pass, which is host to one of the world’s largest
Isostatic gravity map of Mountain Pass and vicinity, California and Nevada
Gravity investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain Pass, which is host to one of the world’s largest r
Geophysical and geologic maps of Mountain Pass and vicinity, California and Nevada
U.S. Geological Survey Scientific Investigations Map 3412 is a series of products that consists of geophysical and geologic maps of Mountain Pass and vicinity, California. Maps A and B (red outline in above map image) are gravity and aeromagnetic maps, respectively. The map series was begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework
Three-Dimensional Geologic Map of the Hayward Fault Zone, San Francisco Bay Region, California
Bouguer gravity map of Nevada: Vya sheet
Aeromagnetic map of the Death Valley ground-water model area, Nevada and California
Map showing depth to pre-Cenozoic basement in the Death Valley ground-water model area, Nevada and California
Isostatic gravity map of the Death Valley ground-water model area, Nevada and California
Isostatic gravity map of the Battle Mountain 30 x 60 minute quadrangle, north central Nevada
Focus areas for data acquisition for potential domestic resources of 13 critical minerals in the conterminous United States and Puerto Rico — Antimony, barite, beryllium, chromium, fluorspar, hafnium, helium, magnesium, manganese, potash, uranium, vanadiu
A geology and geodesy based model of dynamic earthquake rupture on the Rodgers Creek‐Hayward‐Calaveras Fault System, California
Focus areas for data acquisition for potential domestic resources of 11 critical minerals in the conterminous United States, Hawaii, and Puerto Rico—Aluminum, cobalt, graphite, lithium, niobium, platinum-group elements, rare earth elements, tantalum, tin,
The US Geological Survey’s Earth Mapping Resources Initiative (Earth MRI)—Providing framework geologic, geophysical, and elevation data to the nation’s critical mineral-bearing regions
Geophysical characterization of a Proterozoic REE terrane at Mountain Pass, eastern Mojave Desert, California
Strike-slip fault interactions at Ivanpah Valley, California and Nevada
The Evergreen basin and the role of the Silver Creek fault in the San Andreas fault system, San Francisco Bay region, California
Missing link between the Hayward and Rodgers Creek faults
Marine magnetic survey and onshore gravity and magnetic survey, San Pablo Bay, northern California
Gravity and magnetic studies of the eastern Mojave Desert, California and Nevada
Imaging the magmatic system of Mono Basin, California with magnetotellurics in three--dimensions
A summary of the late Cenozoic stratigraphic and tectonic history of the Santa Clara Valley, California
Science and Products
- Science
Rare Earth Element Deposits in the Southeast Mojave Desert
In an effort to better understand domestic resource potential, the USGS is investigating the genetic relationship between rare earth element deposits at Mountain Pass, California and Music Valley (Pinto Mountains, California) and extend these studies across a 130-km long belt of alkaline Proterozoic rocks in the southeast Mojave Desert. Such a combined study would significantly improve our... - Data
Gravity Data in the eastern Mojave Desert, California and Nevada
The U.S. Geological Survey (USGS) collected gravity data in the eastern Mojave Desert, California and Nevada as an aid to characterizing the regional geologic framework. Gravity stations were located between approximately lat 35°10’ and 35°50’ N. and long 115°05’ and 115°50’ W. and were distributed from west to east across parts of Shadow Valley, Clark Mountain Range, Mescal Range, Ivanpah Valley,Density and Magnetic Properties of Selected Rock Samples from the Western U.S. and Alaska
The U.S. Geological Survey (USGS) has collected or incorporated over 20,000 physical property measurements into an ASCII database. These data are primarily from the western U.S. and Alaska and are dominated by granitic rock samples from the Sierra Nevada (compiled by Sikora and others, 1991), but also include a range of other commonly found rocks types. The data include density, magnetic susceptibHigh-Resolution Airborne Gravity Gradiometry, Magnetic, and Radiometric Data of Mountain Pass, Southeast Mojave Desert, California
A detailed airborne gravity gradiometry, magnetic, and radiometric survey of Mountain Pass, California was flown by CGG Canada Services Ltd. (CGG). The high-resolution helicopter survey was flown at a flight-line spacing of 100 and 200 m, a flight-line azimuth of 70 degrees, a nominal flight-line elevation above ground of 70 m, and consists of about 1,814 line-kilometers. Tie lines were spaced atHigh-Resolution Airborne Radiometric Survey of Mountain Pass, California
A detailed airborne radiometric survey of Mountain Pass, California was flown by CGG Canada Services Ltd. (CGG). The high-resolution helicopter survey was flown at a flight-line spacing of 100 and 200 m, a flight-line azimuth of 70 degrees, a nominal flight-line elevation above ground of 70 m, and consists of about 1,814 line-kilometers. Tie lines were spaced at a 1-km interval with a flight-lineDensity and magnetic properties of selected plutons (granitoids) in the Great Basin, parts of California, Nevada, Oregon, Utah, and Arizona
The U.S. Geological Survey (USGS) collected over 1,840 physical property measurements on selected plutons in the Great Basin, primarily in California and Nevada. Data include station identifier, geographic coordinates, rock type, density, magnetic susceptibility, remanent magnetization, declination, and inclination where available. Data are presented in ASCII format and include density and magnetiHigh-Resolution Aeromagnetic Survey of Mono Basin and Long Valley, California
A detailed aeromagnetic survey of Mono Basin and Long Valley, California was flown by EON Geosciences Inc. from October 25th to November 11th, 2012. The high-resolution helicopter survey was flown at a flightline spacing of 400 m, a flightline azimuth of 65 degrees, a nominal flightline elevation above ground of 150 m, and consists of about 6,125 line-kilometers. Tie lines were spaced at a 4-km inWhole Rock Density, Magnetic Susceptibility, and Radiometric Measurements of a Rare Earth Element Terrane, Southeastern Mojave Desert.
Efforts by the USGS to characterize regional geology of the southeastern Mojave Desert near Mountain Pass, California, include 1,061 rock samples collected along the southern California/Nevada border. Rock property measurements include density, magnetic susceptibility, and radiometric concentrations to understand structural and geophysical relationships associated with rare earth element mineral dAirborne magnetic and radiometric survey of the southeast Mojave Desert, California and Nevada
A high-resolution airborne magnetic and radiometric survey of the southeast Mojave Desert, parts of California and Nevada was flown by EDCON-PRJ, Inc. from December 13, 2019 to March 21, 2020. The high-resolution fixed-wing survey was flown at a flightline spacing of 200 m, an azimuth of 70 degrees, a nominal elevation above ground of 100 m, and consists of about 17,277 line-kilometers. Tie linesMagnetotelluric data from San Pablo Bay, California
This dataset consists of 14 magnetotelluric (MT) stations collected in 2015 near San Pablo Bay, California along a east-northeast profile. The U.S. Geological Survey acquired these data to understand the fault geometry of the Hayward Fault and the Rodgers Creek Fault.GIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements
In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.). Acquiring information on possible domestic sources of these critical minerals is the basis of the USGS Earth MappiHigh-Resolution Aeromagnetic Survey of Mountain Pass, California
A detailed aeromagnetic survey of Mountain Pass, California was flown by CGG Canada Services Ltd. (CGG) during November and December, 2016. The high-resolution helicopter survey was flown at a flightline spacing of 100 and 200 m, a flightline azimuthal direction of 70 degrees, a nominal flightline elevation above ground of 70 m, and consists of about 1,814 line-kilometers. Tie lines were spaced atDepth to pre-Cenozoic bedrock in northern Nevada
This digital raster dataset represents depth to pre-Cenozoic bedrock in northern Nevada as published in Chapter 6: Geophysical Methods and Application in U.S. Geological Survey Bulletin 2218, Assessment of Metallic and Mineral Resources in the Humboldt River Basin, Northern Nevada by D.A. Ponce. The data are represented on figure 6-9 in this publication and were later provided as raster format geo - Maps
Airborne radiometric maps of Mountain Pass, California
Geophysical investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area encompasses Mountain Pass, host to one of the world’s largest rare earth element carbonatite deposits. The deposit is found along a north-northwest-trending,
Aeromagnetic map of Mountain Pass and vicinity, California and Nevada
Magnetic investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain Pass, which is host to one of the world’s largest
Isostatic gravity map of Mountain Pass and vicinity, California and Nevada
Gravity investigations of Mountain Pass and vicinity were begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework and mineral resources of the eastern Mojave Desert. The study area, which straddles the state boundary between southeastern California and southern Nevada, encompasses Mountain Pass, which is host to one of the world’s largest r
Geophysical and geologic maps of Mountain Pass and vicinity, California and Nevada
U.S. Geological Survey Scientific Investigations Map 3412 is a series of products that consists of geophysical and geologic maps of Mountain Pass and vicinity, California. Maps A and B (red outline in above map image) are gravity and aeromagnetic maps, respectively. The map series was begun as part of an effort to study regional crustal structures as an aid to understanding the geologic framework
Three-Dimensional Geologic Map of the Hayward Fault Zone, San Francisco Bay Region, California
A three-dimensional (3D) geologic map of the Hayward Fault zone was created by integrating the results from geologic mapping, potential field geophysics, and seismology investigations. The map volume is 100 km long, 20 km wide, and extends to a depth of 12 km below sea level. The map volume is oriented northwest and is approximately bisected by the Hayward Fault. The complex geologic structure ofBouguer gravity map of Nevada: Vya sheet
No abstract available.Aeromagnetic map of the Death Valley ground-water model area, Nevada and California
No abstract available.Map showing depth to pre-Cenozoic basement in the Death Valley ground-water model area, Nevada and California
A depth to basement map of the Death Valley groundwater model area was prepared using over 40,0000 gravity stations as part of an interagency effort by the U.S. Geological Survey and the U.S. Department of Energy to help characterize the geology and hydrology of southwest Nevada and parts of California.Isostatic gravity map of the Death Valley ground-water model area, Nevada and California
An isostatic gravity map of the Death Valley groundwater model area was prepared from over 40,0000 gravity stations as part of an interagency effort by the U.S. Geological Survey and the U.S. Department of Energy to help characterize the geology and hydrology of southwest Nevada and parts of California.Isostatic gravity map of the Battle Mountain 30 x 60 minute quadrangle, north central Nevada
Gravity investigations of the Battle Mountain 30 x 60 minute quadrangle were begun as part of an interagency effort by the U.S. Geological Survey (USGS) and the Bureau of Land Management to help characterize the geology, mineral resources, hydrology, and ecology of the Humboldt River Basin in north-central Nevada. The Battle Mountain quadrangle is located between 40°30' and 41°N. lat. and 116° and - Publications
Filter Total Items: 117
Focus areas for data acquisition for potential domestic resources of 13 critical minerals in the conterminous United States and Puerto Rico — Antimony, barite, beryllium, chromium, fluorspar, hafnium, helium, magnesium, manganese, potash, uranium, vanadiu
The Earth Mapping Resources Initiative (Earth MRI) is conducted in phases to identify areas for acquiring new geologic framework data to identify potential domestic resources of the 35 mineral materials designated as critical minerals for the United States. This report describes the data sources and summary results for 13 critical minerals evaluated in the conterminous United States and Puerto RicAuthorsJane M. Hammarstrom, Connie L. Dicken, Laurel G. Woodruff, Allen K. Andersen, Sean T. Brennan, Warren C. Day, Benjamin J. Drenth, Nora K. Foley, Susan Hall, Albert H. Hofstra, Anne E. McCafferty, Anjana K. Shah, David A. PonceByEnergy and Minerals Mission Area, Mineral Resources Program, Central Energy Resources Science Center, Geology, Energy & Minerals Science Center, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center, Earth Mapping Resources Initiative (Earth MRI)A geology and geodesy based model of dynamic earthquake rupture on the Rodgers Creek‐Hayward‐Calaveras Fault System, California
The Hayward fault in California's San Francisco Bay area produces large earthquakes, with the last occurring in 1868. We examine how physics‐based dynamic rupture modeling can be used to numerically simulate large earthquakes on not only the Hayward fault, but also its connected companions to the north and south, the Rodgers Creek and Calaveras faults. Equipped with a wealth of images of this faulAuthorsRuth A. Harris, Michael Barall, David A. Lockner, Diane E. Moore, David A. Ponce, Russell Graymer, Gareth J. Funning, Carolyn A. Morrow, Christodoulos Kyriakopoulos, Donna Eberhart-PhillipsFocus areas for data acquisition for potential domestic resources of 11 critical minerals in the conterminous United States, Hawaii, and Puerto Rico—Aluminum, cobalt, graphite, lithium, niobium, platinum-group elements, rare earth elements, tantalum, tin,
In response to a need for information on potential domestic sources of critical minerals, the Earth Mapping Resources Initiative (Earth MRI) was established to identify and prioritize areas for acquisition of new geologic mapping, geophysical data, and elevation data to improve our knowledge of the geologic framework of the United States. Phase 1 of Earth MRI concentrated on those geologic terraneAuthorsJane M. Hammarstrom, Connie L. Dicken, Warren C. Day, Albert H. Hofstra, Benjamin J. Drenth, Anjana K. Shah, Anne E. McCafferty, Laurel G. Woodruff, Nora K. Foley, David A. Ponce, Thomas P. Frost, Lisa L. StillingsThe US Geological Survey’s Earth Mapping Resources Initiative (Earth MRI)—Providing framework geologic, geophysical, and elevation data to the nation’s critical mineral-bearing regions
New detailed mapping of the geologic resources of the Nation has the potential to significantly close the gap in the essential data needed to fuel a modern era of economic development and technological innovation, while at the same time dramatically enhancing our understanding of the fundamental way geology impacts everyday life, from the domestic critical mineral resources that are necessary forAuthorsWarren C. Day, Benjamin J. Drenth, Anne E. McCafferty, Anjana K. Shah, David A. Ponce, James V. Jones, V. J. GrauchGeophysical characterization of a Proterozoic REE terrane at Mountain Pass, eastern Mojave Desert, California
Mountain Pass, California (USA), located in the eastern Mojave Desert, hosts one of the world’s richest rare earth element (REE) deposits. The REE-rich terrane occurs in a 2.5-km-wide, northwest-trending belt of Mesoproterozoic (1.4 Ga) stocks and dikes, which intrude a larger Paleoproterozoic (1.7 Ga) metamorphic block that extends ∼10 km southward from Clark Mountain to the eastern Mescal Range.AuthorsKevin Denton, David A. Ponce, Jared R. Peacock, David M. MillerStrike-slip fault interactions at Ivanpah Valley, California and Nevada
Ivanpah Valley is flanked by high mountain ranges, and represents one of the most imposing valleys of the eastern Mojave Desert. Its sinuous shape implies a complex origin as does the fact that it is not bordered by prominent range-front normal faults like valleys of the Basin and Range Province. In Addition, its deepest sedimentary basin is restricted to a small part of the valley near Nipton thaAuthorsDavid M. Miller, Victoria E. Langenheim, Kevin Denton, David A. PonceThe Evergreen basin and the role of the Silver Creek fault in the San Andreas fault system, San Francisco Bay region, California
The Evergreen basin is a 40-km-long, 8-km-wide Cenozoic sedimentary basin that lies mostly concealed beneath the northeastern margin of the Santa Clara Valley near the south end of San Francisco Bay (California, USA). The basin is bounded on the northeast by the strike-slip Hayward fault and an approximately parallel subsurface fault that is structurally overlain by a set of west-verging reverse-oAuthorsRobert C. Jachens, Carl M. Wentworth, Russell W. Graymer, Robert Williams, David A. Ponce, Edward A. Mankinen, William J. Stephenson, Victoria E. LangenheimMissing link between the Hayward and Rodgers Creek faults
The next major earthquake to strike the ~7 million residents of the San Francisco Bay Area will most likely result from rupture of the Hayward or Rodgers Creek faults. Until now, the relationship between these two faults beneath San Pablo Bay has been a mystery. Detailed subsurface imaging provides definitive evidence of active faulting along the Hayward fault as it traverses San Pablo Bay and benAuthorsJanet Watt, David A. Ponce, Thomas E. Parsons, Patrick E. HartMarine magnetic survey and onshore gravity and magnetic survey, San Pablo Bay, northern California
IntroductionFrom November 2011 to August 2015, the U.S. Geological Survey (USGS) collected more than 1,000 line-kilometers (length of lines surveyed in kilometers) of marine magnetic data on San Pablo Bay, 98 onshore gravity stations, and over 27 line-kilometers of ground magnetic data in northern California. Combined magnetic and gravity investigations were undertaken to study subsurface geologicAuthorsDavid A. Ponce, Kevin M. Denton, Janet Tilden WattGravity 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 crustal structures as an aid to understanding the geologiAuthorsKevin M. Denton, David A. PonceImaging 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 which a 3D electrical resistivity model was created with a resolAuthorsJared R. Peacock, Margaret T. Mangan, Darcy McPhee, David A. PonceA 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 in places with Coast Range ophiolite and Mesozoic GAuthorsVictoria E. Langenheim, Robert C. Jachens, Carl M. Wentworth, Russell W. Graymer, Richard G. Stanley, Robert J. McLaughlin, Robert W. Simpson, Robert A. Williams, D. W. Andersen, David A. Ponce - News
*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