Amy Gilmer, PhD
I am an igneous petrologist interested in the role magmatic processes play in driving plate tectonics, building mountains, forming of volcanic belts and their associated geologic hazards, and forming hydrothermal ore deposits.
My research is focused on the evolution of magmatic systems. I study extinct systems, using exposures to explore internal processes driving magma, analogous to the plumbing systems feeding active volcanoes. I combine field geology, geochronology, geochemistry, and petrology to constrain conditions of magmatic storage and differentiation that result in either eruption or pluton emplacement and help us understand the larger architecture of magmatic systems.
Professional Experience
Research Geologist (2018-present)
Postdoctoral Fellow, U.S. Geological Survey (2017-2018)
Geologist, Virginia Division of Geology and Mineral Resources (2001-2012)
Education and Certifications
Ph.D., Geological Science, University of Bristol (2016)
M.S., Geological Science, The University of Texas at Austin (2001)
B.S., Geology, College of William and Mary (1999)
Science and Products
Filter Total Items: 16
Zircon U-Pb data for Proterozoic rocks in southwestern Colorado and rocks from drill core from Wyoming, Montana, and Nebraska Zircon U-Pb data for Proterozoic rocks in southwestern Colorado and rocks from drill core from Wyoming, Montana, and Nebraska
This U.S. Geological Survey (USGS) data release provides U-Pb zircon data and geochronology for Proterozoic rocks in the Needle Mountains of southwestern Colorado and for Proterozoic rocks sampled from drill cores from Wyoming, Montana, and Nebraska. Samples from the Needle Mountains were collected in order to constrain the polyphase tectonic evolution of the area. Drill core samples are...
Data release of geochemistry and geochronology for Proterozoic rocks in southwestern Colorado and rocks from drill core from Colorado, North Dakota, Nevada, Wyoming, Montana, and Nebraska Data release of geochemistry and geochronology for Proterozoic rocks in southwestern Colorado and rocks from drill core from Colorado, North Dakota, Nevada, Wyoming, Montana, and Nebraska
This U.S. Geological Survey (USGS) data release provides whole rock major, minor, and trace element geochemical data, mineral chemistry, and monazite and xenotime geochronology for Proterozoic rocks in the Needle Mountains of southwestern Colorado and for Proterozoic rocks sampled from drill cores from Colorado, North Dakota, Nevada, Wyoming, Montana, and Nebraska. Samples from the...
USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 4.0, May 2025) USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 4.0, May 2025)
USGS Geochron is a database of geochronological and thermochronological dates and data. The data set contains published ages, dates, analytical information, sample metadata including location, and source citations. The following analytical techniques are represented in the data set: 40Ar/39Ar, K-Ar, U-Th-Pb, Sm-Nd, Rb-Sr, Lu-Hf, fission track, luminescence, U-series, (U-Th)/He, Re-Os...
Data Release for Geologic Map of Petroglyph National Monument and Vicinity, Bernalillo County, New Mexico Data Release for Geologic Map of Petroglyph National Monument and Vicinity, Bernalillo County, New Mexico
This geologic map depicts and briefly describes geologic units underlying Petroglyph National Monument and immediately adjacent areas in Bernalillo County, New Mexico. The Monument is underlain dominantly by Quaternary basalts of the Albuquerque Volcanoes volcanic field, a series of basin-filling volcanic flows and associated vents from a monogenetic volcanic highland along the eastern...
Filter Total Items: 17
Postcaldera intrusive magmatism at the Platoro caldera complex, Southern Rocky Mountain volcanic field, Colorado, USA Postcaldera intrusive magmatism at the Platoro caldera complex, Southern Rocky Mountain volcanic field, Colorado, USA
The Oligocene Platoro caldera complex of the San Juan volcanic locus in Colorado (USA) features numerous exposed plutons both within the caldera and outside its margins, enabling investigation of the timing and evolution of postcaldera magmatism. Intrusion whole-rock geochemistry and phenocryst and/or mineral trace element compositions coupled with new zircon U-Pb geo-chronology and...
Authors
Amy K. Gilmer, Ren A. Thompson, Peter W. Lipman, Jorge A. Vazquez, Amanda Souders
Duration of hydrothermal alteration and mineralization of the Don Manuel porphyry copper system, central Chile Duration of hydrothermal alteration and mineralization of the Don Manuel porphyry copper system, central Chile
The Don Manuel porphyry copper system, located in the Miocene–Pliocene metallogenic belt of central Chile, contains spatially zoned alteration styles common to other porphyry copper deposits including extensive potassic alteration, propylitic alteration, localized sericite-chlorite alteration and argillic alteration but lacks pervasive hydrolytic alteration typical of some deposits. It...
Authors
Amy K. Gilmer, R. Stephen J. Sparks, Dan N. Barfod, Emily Brugge, Catherine Annen, Ian Parkinson
Protracted multipulse emplacement of a post-resurgent pluton: The case of Platoro caldera complex (Southern Rocky Mountain volcanic field, Colorado) Protracted multipulse emplacement of a post-resurgent pluton: The case of Platoro caldera complex (Southern Rocky Mountain volcanic field, Colorado)
Many eroded calderas expose associated postcollapse plutons, but detailed fieldwork‐supported studies have rarely focused on the internal structure that can contribute to understanding of emplacement dynamics. The Alamosa River monzonite pluton is a postcollapse intrusion at the Platoro caldera complex that erupted six large ignimbrites between 30.2 and 28.8 Ma in the Southern Rocky...
Authors
Filip Tomek, Amy K. Gilmer, M. S. Petronis, Peter W. Lipman, M. S. Foucher
A supervolcano and its sidekicks: A 100 ka eruptive chronology of the Fish Canyon Tuff and associated units of the La Garita magmatic system A supervolcano and its sidekicks: A 100 ka eruptive chronology of the Fish Canyon Tuff and associated units of the La Garita magmatic system
Establishing temporal constrains on major volcanic eruptions is limited by the precision of existing geochronometers. Prior work on the La Garita caldera, created by the eruption of the Fish Canyon Tuff, failed to resolve temporal differences between pre-, syn-, and post-collapse eruptive units. Here, we report 40Ar/39Ar geochronologic data supporting a ca. 100 ka eruptive history of the...
Authors
Leah E. Morgan, Samuel Johnstone, Amy K. Gilmer, Michael A. Cosca, Ren A. Thompson
Subsurface geologic features of the 2011 central Virginia earthquakes revealed by airborne geophysics Subsurface geologic features of the 2011 central Virginia earthquakes revealed by airborne geophysics
Characterizing geologic features associated with major earthquakes provides insights into mechanisms contributing to fault slip and assists evaluation of seismic hazard. We use high-resolution airborne geophysical data combined with ground sample measurements to image subsurface geologic features associated with the 2011 moment magnitude (Mw) 5.8 central Virginia (USA) intraplate...
Authors
Anjana K. Shah, J. Wright Horton, William C. Burton, David Spears, Amy K Gilmer
Non-USGS Publications**
Gilmer, A.K., Sparks, R.S.J., Rust, A.C., Tapster, Simon, Webb, A.D., and Barfod, D.N., Geology of the Don Manuel igneous complex, central Chile: Implications for igneous processes in porphyry copper systems:GSA Bulletin, 129 (7-8): 920–946.
Blundy, J., Mavrogenes, J., Tattitch, B., Sparks, S., and Gilmer, A. 2015, Generation of porphyry copper deposits by gas-brine reaction in volcanic arcs: Nature Geoscience, 8, 235-240.
Pratt, T.L., Horton, J.W., Spears, D.B., Gilmer, A.K., and McNamara, D.E., 2014, The 2011 Virginia Mw 5.8 earthquake: Insights from seismic reflection imaging into the influence of older structures on eastern US seismicity: Geological Society of America Special Papers, 509, SPE509-16.
Shah, A.K., Horton, J.W., Burton, W.C., Spears, D.B., and Gilmer, A.K., 2014, Subsurface geologic features of the 2011 central Virginia earthquakes revealed by airborne geophysics: Geological Society of America Special Papers, 509, SPE509-17.
Gilmer, A.K., Kyle, J.R., Connelly, J.N., and Mathur, R.D., and Henry, CD., 2003, Extension of Laramide magmatism in southwestern North America into Trans-Pecos Texas: Geology, v. 31, no. 5, p. 447-450.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 16
Zircon U-Pb data for Proterozoic rocks in southwestern Colorado and rocks from drill core from Wyoming, Montana, and Nebraska Zircon U-Pb data for Proterozoic rocks in southwestern Colorado and rocks from drill core from Wyoming, Montana, and Nebraska
This U.S. Geological Survey (USGS) data release provides U-Pb zircon data and geochronology for Proterozoic rocks in the Needle Mountains of southwestern Colorado and for Proterozoic rocks sampled from drill cores from Wyoming, Montana, and Nebraska. Samples from the Needle Mountains were collected in order to constrain the polyphase tectonic evolution of the area. Drill core samples are...
Data release of geochemistry and geochronology for Proterozoic rocks in southwestern Colorado and rocks from drill core from Colorado, North Dakota, Nevada, Wyoming, Montana, and Nebraska Data release of geochemistry and geochronology for Proterozoic rocks in southwestern Colorado and rocks from drill core from Colorado, North Dakota, Nevada, Wyoming, Montana, and Nebraska
This U.S. Geological Survey (USGS) data release provides whole rock major, minor, and trace element geochemical data, mineral chemistry, and monazite and xenotime geochronology for Proterozoic rocks in the Needle Mountains of southwestern Colorado and for Proterozoic rocks sampled from drill cores from Colorado, North Dakota, Nevada, Wyoming, Montana, and Nebraska. Samples from the...
USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 4.0, May 2025) USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 4.0, May 2025)
USGS Geochron is a database of geochronological and thermochronological dates and data. The data set contains published ages, dates, analytical information, sample metadata including location, and source citations. The following analytical techniques are represented in the data set: 40Ar/39Ar, K-Ar, U-Th-Pb, Sm-Nd, Rb-Sr, Lu-Hf, fission track, luminescence, U-series, (U-Th)/He, Re-Os...
Data Release for Geologic Map of Petroglyph National Monument and Vicinity, Bernalillo County, New Mexico Data Release for Geologic Map of Petroglyph National Monument and Vicinity, Bernalillo County, New Mexico
This geologic map depicts and briefly describes geologic units underlying Petroglyph National Monument and immediately adjacent areas in Bernalillo County, New Mexico. The Monument is underlain dominantly by Quaternary basalts of the Albuquerque Volcanoes volcanic field, a series of basin-filling volcanic flows and associated vents from a monogenetic volcanic highland along the eastern...
Filter Total Items: 17
Postcaldera intrusive magmatism at the Platoro caldera complex, Southern Rocky Mountain volcanic field, Colorado, USA Postcaldera intrusive magmatism at the Platoro caldera complex, Southern Rocky Mountain volcanic field, Colorado, USA
The Oligocene Platoro caldera complex of the San Juan volcanic locus in Colorado (USA) features numerous exposed plutons both within the caldera and outside its margins, enabling investigation of the timing and evolution of postcaldera magmatism. Intrusion whole-rock geochemistry and phenocryst and/or mineral trace element compositions coupled with new zircon U-Pb geo-chronology and...
Authors
Amy K. Gilmer, Ren A. Thompson, Peter W. Lipman, Jorge A. Vazquez, Amanda Souders
Duration of hydrothermal alteration and mineralization of the Don Manuel porphyry copper system, central Chile Duration of hydrothermal alteration and mineralization of the Don Manuel porphyry copper system, central Chile
The Don Manuel porphyry copper system, located in the Miocene–Pliocene metallogenic belt of central Chile, contains spatially zoned alteration styles common to other porphyry copper deposits including extensive potassic alteration, propylitic alteration, localized sericite-chlorite alteration and argillic alteration but lacks pervasive hydrolytic alteration typical of some deposits. It...
Authors
Amy K. Gilmer, R. Stephen J. Sparks, Dan N. Barfod, Emily Brugge, Catherine Annen, Ian Parkinson
Protracted multipulse emplacement of a post-resurgent pluton: The case of Platoro caldera complex (Southern Rocky Mountain volcanic field, Colorado) Protracted multipulse emplacement of a post-resurgent pluton: The case of Platoro caldera complex (Southern Rocky Mountain volcanic field, Colorado)
Many eroded calderas expose associated postcollapse plutons, but detailed fieldwork‐supported studies have rarely focused on the internal structure that can contribute to understanding of emplacement dynamics. The Alamosa River monzonite pluton is a postcollapse intrusion at the Platoro caldera complex that erupted six large ignimbrites between 30.2 and 28.8 Ma in the Southern Rocky...
Authors
Filip Tomek, Amy K. Gilmer, M. S. Petronis, Peter W. Lipman, M. S. Foucher
A supervolcano and its sidekicks: A 100 ka eruptive chronology of the Fish Canyon Tuff and associated units of the La Garita magmatic system A supervolcano and its sidekicks: A 100 ka eruptive chronology of the Fish Canyon Tuff and associated units of the La Garita magmatic system
Establishing temporal constrains on major volcanic eruptions is limited by the precision of existing geochronometers. Prior work on the La Garita caldera, created by the eruption of the Fish Canyon Tuff, failed to resolve temporal differences between pre-, syn-, and post-collapse eruptive units. Here, we report 40Ar/39Ar geochronologic data supporting a ca. 100 ka eruptive history of the...
Authors
Leah E. Morgan, Samuel Johnstone, Amy K. Gilmer, Michael A. Cosca, Ren A. Thompson
Subsurface geologic features of the 2011 central Virginia earthquakes revealed by airborne geophysics Subsurface geologic features of the 2011 central Virginia earthquakes revealed by airborne geophysics
Characterizing geologic features associated with major earthquakes provides insights into mechanisms contributing to fault slip and assists evaluation of seismic hazard. We use high-resolution airborne geophysical data combined with ground sample measurements to image subsurface geologic features associated with the 2011 moment magnitude (Mw) 5.8 central Virginia (USA) intraplate...
Authors
Anjana K. Shah, J. Wright Horton, William C. Burton, David Spears, Amy K Gilmer
Non-USGS Publications**
Gilmer, A.K., Sparks, R.S.J., Rust, A.C., Tapster, Simon, Webb, A.D., and Barfod, D.N., Geology of the Don Manuel igneous complex, central Chile: Implications for igneous processes in porphyry copper systems:GSA Bulletin, 129 (7-8): 920–946.
Blundy, J., Mavrogenes, J., Tattitch, B., Sparks, S., and Gilmer, A. 2015, Generation of porphyry copper deposits by gas-brine reaction in volcanic arcs: Nature Geoscience, 8, 235-240.
Pratt, T.L., Horton, J.W., Spears, D.B., Gilmer, A.K., and McNamara, D.E., 2014, The 2011 Virginia Mw 5.8 earthquake: Insights from seismic reflection imaging into the influence of older structures on eastern US seismicity: Geological Society of America Special Papers, 509, SPE509-16.
Shah, A.K., Horton, J.W., Burton, W.C., Spears, D.B., and Gilmer, A.K., 2014, Subsurface geologic features of the 2011 central Virginia earthquakes revealed by airborne geophysics: Geological Society of America Special Papers, 509, SPE509-17.
Gilmer, A.K., Kyle, J.R., Connelly, J.N., and Mathur, R.D., and Henry, CD., 2003, Extension of Laramide magmatism in southwestern North America into Trans-Pecos Texas: Geology, v. 31, no. 5, p. 447-450.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.