Geology, Minerals, Energy, and Geophysics Science Center
Publications
Geologic framework of Mount Diablo, California
The basic stratigraphic and structural framework of Mount Diablo is described using a revised geologic map, gravity data, and aeromagnetic data. The mountain is made up of two distinct stratigraphic assemblages representing different depocenters that were juxtaposed by ~20 km of late Pliocene and Quaternary right-lateral offset on the Greenville-...
Graymer, Russell; Langenheim, Victoria Global biotic events evident in the Paleogene marine strata of the eastern San Francisco Bay area, California
Paleogene marine strata in the eastern San Francisco Bay area are exposed in discontinuous outcrops in the various tectonic blocks. Although there are many missing intervals, the strata were previously thought to span most of the Paleocene and Eocene. Revision of biochronology and calibration to the international time scale as well as to the...
McDougall-Reid, Kristin
Mineral resource inventory of North Dakota
Aside from construction aggregate materials, the value of nonfuel mineral commodities that have been produced in North Dakota is small, although there is potential for the existence of several mineral resource deposit types which are not economically viable at this time. In this report, we present a mineral resource inventory of the State of North...
Box, Stephen E.; Cossette, Pamela M.
Geologic and geophysical maps of the Santa Maria and part of the Point Conception 30'×60' quadrangles, California
This report presents digital geologic, gravity, and aeromagnetic maps for the onshore parts of the Santa Maria and Point Conception 30'x60' quadrangles at a compilation scale of 1:100,000. The map depicts the distribution of bedrock units, surficial deposits, paleontological data, geophysical data and structural features in the Santa Maria basin...
Sweetkind, Donald S.; Langenheim, Victoria E.; McDougall-Reid, Kristin; Sorlien, Christopher C.; Demas, Shiera C.; Tennyson, Marilyn E.; Johnson, Samuel Y. Past abrupt changes, tipping points and cascading impacts in the Earth system
The geological record shows that abrupt changes in the Earth system can occur on timescales short enough to challenge the capacity of human societies to adapt to environmental pressures. In many cases, abrupt changes arise from slow changes in one component of the Earth system that eventually pass a critical threshold, or tipping point, after...
Brovkin, V.; Brook, Edward J.; Williams, J.; Bathiany, S.; Lenton, T.; Barton, M.; DeConto, R.; Donges, J.; Ganopolski, A.; McManus, J.; Praetorius, Summer K.; de Vernal, A.; Abe-Ouchi, A.; Cheng, H.; Claussen, M; Crucifix, M.; Iglesias, Virginia; Kaufman, Darrell S.; Kleinen, T.; Lambert, Fabrice; van der Leeuw, Sander; Liddy, Hannah; Loutre, Marie-France; McGee, David; Rehfeld, Kira; Rhodes, Rachael H.; Seddon, Alistair W.R.; Vanderveken, Lilian; Yu, Zicheng Temporal and petrogenetic links between Mesoproterozoic alkaline and carbonatite magmas at Mountain Pass, California
Mountain Pass is the site of the most economically important rare earth element (REE) deposit in the United States. Mesoproterozoic alkaline intrusions are spatiotemporally associated with a composite carbonatite stock that hosts REE ore. Understanding the genesis of the alkaline and carbonatite magmas is an essential scientific goal for a society...
Watts, Kathryn E.; Haxel, Gordon B.; Miller, David M. The Miocene stratigraphy of the Laberinto area (Río Ica Valley) and its bearing on the geological history of the East Pisco Basin (south-central Peru)
Global sea-level changes and substantial vertical displacement along the Monte Grande Fault (MGF) in the lower Río Ica Valley of south-central Peru influenced the accumulation of bioclast-bearing and diatom-bearing Miocene siliciclastic sediments in an area of the East Pisco forearc basin (EPB) colloquially known as Laberinto. Two depositional...
Devries, Thomas J.; Barron, John A.; Urbina-Schmitt, Mario; Ochoa, Diana; Esperante, Raúl; Snee, Lawrence W Geologic and geophysical maps of the Newfoundland Mountains and part of the adjacent Wells 30' x 60' quadrangles, Box Elder County, Utah
The Newfoundland Mountains map area (Newfoundland Mountains and adjacent part of Wells 30' x 60' quadrangles) is located in Box Elder County, northwestern Utah. The map encompasses broad expanses of the Great Salt Lake Desert as well as several picturesque mountain ranges (figures 1, 2, and 3). The geology of the area was last mapped and...
Miller, David M.; Felger, Tracey J.; Langenheim, Victoria E. Machine learning to identify geologic factors associated with production in geothermal fields: A case-study using 3D geologic data, Brady geothermal field, Nevada
In this paper, we present an analysis using unsupervised machine learning (ML) to identify the key geologic factors that contribute to the geothermal production in Brady geothermal field. Brady is a hydrothermal system in northwestern Nevada that supports both electricity production and direct use of hydrothermal fluids. Transmissive fluid-flow...
Siler, Drew L.; Pepin, Jeff D.; Vesselinov, Velimir V.; Mudunuru, Maruti K.; Ahmmed, Bulbul Relative risk of groundwater-quality degradation near California (USA) oil fields estimated from 3H, 14C, and 4He
Relative risks of groundwater-quality degradation near selected California oil fields are estimated by examining spatial and temporal patterns in chemical and isotopic data in the context of groundwater-age categories defined by tritium and carbon-14. In the Coastal basins, western San Joaquin Valley (SJV), and eastern SJV; 82, 76, and 0...
McMahon, Peter B.; Landon, Matthew K.; Davis, Tracy; Wright, Michael; Rosecrans, Celia Z.; Anders, Robert; Land, Michael; Kulongoski, Justin T.; Hunt, Andrew Ten years of volcanic activity at Mt Etna: High-resolution mapping and accurate quantification of the morphological changes by Pleiades and Lidar data
The topography of Mt. Etna, Italy, is subjected to continuous modifications depending on intensity and magnitude of eruptions that frequently occur at the volcano summit and flanks. In order to make high-resolution maps of morphological changes and accurately calculate the overall volume of the erupted products (e.g., lava flows, tephra fall out,...
Bisson, Marina; Spinetti, Claudia; Andronico, Daniele; Palaseanu-Lovejoy, Monica; Buongiorno, Maria Fabrizia; Alexandrov, Oleg; Cecere, Thomas Comment on ‘New insights on Franciscan Complex geology, architecture, depositional age, and provenance for the western Mt. Tamalpais area, Marin County, California’ by Bero et al. (2020)
Serious errors and inconsistencies in the article undermine many of its interpretations to the point that principal conclusions are not valid. Much dependence is placed on the maximum depositional age (Dmax) of sandstone units based on zircon analysis of 10 samples, but calculation of those Dmax values is flawed, and their use confuses maximum...
Graymer, Russell; Dumitru, Trevor A.; McLaughlin, Robert J.; Wentworth, Carl M.