Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2354
Repeat magnetotelluric measurements to monitor The Geysers steam field in northern California
The Geysers in northern California is the world’s largest electricity generating steam field. To help understand changes in the steam reservoir, repeat magnetotelluric (MT) measurements are being collected once a year from 2021-2023. These data will be compared and modeled to provide 4-D images of changes within the reservoir. Joint inversion with passive seismic data will be done to further co
Authors
Jared R. Peacock, David Alumbaugh, Michael Albert Mitchell, Craig Hartline
Rockfall kinematics from massive rock cliffs: Outlier boulders and flyrock from Whitney Portal, California, rockfalls
Geologic conditions and topographic setting are among the most critical factors for assessing rockfall hazards. However, other subtle features of rockfall motion may also govern the runout of rockfall debris, particularly for those sourced from massive cliffs where debris can have substantial momentum during transport. Rocks may undergo collisions with trees and talus boulders, with the latter pot
Authors
Brian D. Collins, Skye C. Corbett, Elizabeth Jean Horton, Alan J. Gallegos
Preliminary bedrock geologic map of the Blythe 30' x 60' quadrangle, California and Arizona
The Blythe 30' x 60' quadrangle in southeastern California and southwestern Arizona displays complex geology that includes Mesozoic contractional deformation, metamorphism, and magmatism in addition to Cenozoic extensional deformation and magmatism. Previous geologic map compilations predate recent geologic mapping efforts that have contributed new insights into the stratigraphy and structure of t
Multidisciplinary constraints on the thermal-chemical boundary between Earth's core and mantle
Heat flux from the core to the mantle provides driving energy for mantle convection thus powering plate tectonics, and contributes a significant fraction of the geothermal heat budget. Indirect estimates of core-mantle boundary heat flow are typically based on petrological evidence of mantle temperature, interpretations of temperatures indicated by seismic travel times, experimental measurements o
Authors
Daniel A. Frost, Margaret Susan Avery, Bruce Buffett, Bethany A. Chidester, Jie Deng, Susannah M. Dorfman, Zhi Li, Lijun Liu, Mingda Lv, Joshua F. Martin
Deconstructing the microbial necromass continuum to inform soil carbon sequestration
Microbial necromass is a large, dynamic and persistent component of soil organic carbon, the dominant terrestrial carbon pool. Quantification of necromass carbon stocks and its susceptibility to global change is becoming standard practice in soil carbon research. However, the typical proxies used for necromass carbon do not reveal the dynamic nature of necromass carbon flows and transformations wi
Authors
Kate M Buckeridge, Courtney Creamer, Jeanette Whitaker
Modeling subsurface performance of a geothermal reservoir using machine learning
Geothermal power plants typically show decreasing heat and power production rates over time. Mitigation strategies include optimizing the management of existing wells—increasing or decreasing the fluid flow rates across the wells—and drilling new wells at appropriate locations. The latter is expensive, time-consuming, and subject to many engineering constraints, but the former is a viable mechanis
Authors
Dmitry Duplyakin, Koenraad F Beckers, Drew L. Siler, Michael J. Martin, Henry E. Johnston
Major reorganization of the Snake River modulated by passage of the Yellowstone Hotspot
The details and mechanisms for Neogene river reorganization in the U.S. Pacific Northwest and northern Rocky Mountains have been debated for over a century with key implications for how tectonic and volcanic systems modulate topographic development. To evaluate paleo-drainage networks, we produced an expansive data set and provenance analysis of detrital zircon U-Pb ages from Miocene to Pleistocen
Authors
Lydia M. Staisch, Jim E. O'Connor, Charles M. Cannon, Christopher Holm-Denoma, Paul K. Link, John Lasher, Jeremy A. Alexander
Geology and hydrogeology of the Yucaipa groundwater subbasin, San Bernardino and Riverside Counties, California
The Yucaipa groundwater subbasin (referred to in this report as the Yucaipa subbasin) is located about 75 miles (mi) east of of Los Angeles and about 12 mi southeast of the City of San Bernardino. In the Yucaipa subbasin, as in much of southern California, limited annual rainfall and large water demands can strain existing water supplies; therefore, understanding local surface water and groundwate
Authors
Geoffrey Cromwell, Jonathan C. Matti
Early Pliocene marine transgression into the lower Colorado River valley, southwestern USA, by re-flooding of a former tidal strait
Marine straits and seaways are known to host a wide range of sedimentary processes and products, but the role of marine connections in the development of large river systems remains little studied. This study explores a hypothesis that shallow-marine waters flooded the lower Colorado River valley at c. 5 Ma along a fault-controlled former tidal strait, soon after the river was first integrated int
Authors
Rebecca Dorsey, Juan Carlos Braga, Kevin Gardner, Kristin McDougall-Reid, Brennan O’Connell
UAS-based tools for mapping and monitoring hydrothermal systems: An example from Mammoth Lakes, California
Unoccupied Aerial Systems (UAS) can accommodate a variety of tools for mapping and monitoring hydrothermal systems (e.g., magnetic, gas, photogrammetry, and thermal infrared [TIR]). These platforms offer increased speed, coverage area, and uniformity compared to ground-based measurements, as well as lower flight height – and therefore higher resolution – than occupied aircraft.
We adapted a suite
Authors
Laurie Antoinette Zielinski, Jonathan M.G. Glen, Tait E. Earney, Grant H. Rea-Downing, R. Greg Vaughan, Peter J. Kelly, Gordon H. Keller, Branden James Dean, William Schermerhorn
Coastal paleogeography of the Pacific Northwest, USA, for the last 12,000 years accounting for three-dimensional earth structure
Predictive modeling of submerged archaeological sites requires accurate sea-level predictions in order to reconstruct coastal paleogeography and associated geographic features that may have influenced the locations of occupation sites such as rivers and embayments. Earlier reconstructions of the paleogeography of parts of the western U.S. coast used an assumption of eustatic sea level, but this ne
Authors
Jorie Clark, Jay R. Alder, Marisa Borreggine, Jerry X Mitrovica, Konstantin Latychev
Maybe so, maybe not: Canis lepophagus at Hagerman Fossil Beds National Monument, Idaho, USA
A canid dentary is described from the Pliocene Glenns Ferry Formation at Hagerman Fossil Beds National Monument, south-central Idaho, USA. The specimen possesses traits in alliance with and measurements falling within or exceeding those of Canis lepophagus. The dentary, along with a tarsal IV (cuboid) and an exploded canine come from the base of the fossiliferous Sahara complex within the monument
Authors
Kari A Prassack, Laura Walkup