Michelle Coombs is a Research Geologist with the U.S. Geological Survey Volcanic Science Center. Since 2016, she has served as Scientist-in-Charge of the Alaska Volcano Observatory. In this position, Dr. Coombs leads eruption responses, oversees expansion and modernization of volcano monitoring techniques, and guides applied and fundamental research on a host of problems related to volcanology.
Professional Experience
2016–present: Scientist-in-Charge, Alaska Volcano Observatory, Volcano Science Center, U.S. Geological Survey, Anchorage, AK
2004–2016: Research Geologist, Alaska Volcano Observatory
2001–2004: Research Geologist, Volcano Hazards Team, U.S. Geological Survey, Menlo Park CA
OTHER PROFESSIONAL ACTIVITIES
Affiliate faculty, University of Alaska Fairbanks
CONVERSE Steering Committee member, 2020–present
Member of AGU student awards committee, 2011–2015
Associate Editor, Bulletin of Volcanology, 2013–2016
Editorial board, Journal of Volcanology and Geothermal Research, 2007–2018
Co-editor for 28-chapter USGS Professional Paper 1769, The 2006 eruption of Augustine Volcano, Alaska, 2010
Co-editor for Journal of Volcanology and Geothermal Research special issue on Growth and collapse of Hawaiian volcanoes, 2006
Education and Certifications
Williams College, BA Geology, 1994
University of Alaska Fairbanks, PhD Geology, 2001
Affiliations and Memberships*
American Geophysical Union, 1996–present
Geological Society of America, 2001–present (elected Fellow in 2015)
International Assoc. of Volcanology and Chemistry of the Earth’s Interior, 1999–present
Science and Products
Digital geologic map data for Semisopochnoi Island, Alaska
This dataset contains digital data that were used for the creation of a geologic map shown in Figure 3 in USGS SIR 2017-5150; Postglacial Eruptive History and Geochemistry of Semisopochnoi Volcano, Western Aleutian Islands, Alaska by Coombs, M.L. and others. The map shows the generalized geology of the island and the locations of stations occupied during field work conducted in the summer of 2005.
Geologic map of Mount Gareloi, Gareloi Island, Alaska
Gareloi Island (lat 51.7° N., long 178.8° W.) is located in the Delarof Islands group of the Aleutian Islands, approximately 2,000 km west-southwest of Anchorage and 150 km west of Adak, the westernmost town in Alaska. This small (~8- x 10-km diam), uninhabited island is constructed exclusively of eruptive products from Mount Gareloi volcano, a Pleistocene and Holocene, steep-sided, composite stra
Filter Total Items: 69
Coordinating science during an eruption: Lessons from the 2020–2021 Kīlauea volcanic eruption
Data collected during well-observed eruptions can lead to dramatic increases in our understanding of volcanic processes. However, the necessary prioritization of public safety and hazard mitigation during a crisis means that scientific opportunities may be sacrificed. Thus, maximizing the scientific gains from eruptions requires improved planning and coordinating science activities among governmen
Authors
Kari M. Cooper, Kyle R. Anderson, Kathy Cashman, Michelle L. Coombs, Hannah R. Dietterich, Tobias Fischer, Bruce F. Houghton, Ingrid Johanson, Kendra Lynn, Michael Manga, Christelle Wauthier
Generation of calc-alkaline magmas during crystallization at high oxygen fugacity: An experimental and petrologic study of tephras from Buldir Volcano, western Aleutian Arc, Alaska, USA
Despite agreement that calc-alkaline volcanism occurs at subduction zones and is responsible for the genesis of continental landmasses, there is no consensus on the source of the Fe-depleted signature hallmark to calc-alkaline volcanism. In this study, we utilize mafic tephras collected from Buldir Volcano to address the genesis of strongly calc-alkaline volcanic rocks (those with a low Tholeiitic
Authors
Laura Waters, Elizabeth Cottrell, Michelle L. Coombs, Katherine A. Kelley
The eruptive history, magmatic evolution, and influence of glacial ice at long-lived Akutan volcano, eastern Aleutian Islands, Alaska, USA
New 40Ar/39Ar and whole-rock geochemical data are used to develop a detailed eruptive chronology for Akutan volcano, Akutan Island, Alaska, USA, in the eastern Aleutian island arc. Akutan Island (166°W, 54.1°N) is the site of long-lived volcanism and the entire island comprises volcanic rocks as old as 3.3 Ma. Our current study is on the 225 km2 western half of the island, where our results show t
Authors
Michelle L. Coombs, Brian Jicha
U.S. Geological Survey 2018 Kīlauea Volcano eruption response in Hawai'i—After-action review
The 2018 Kīlauea Volcano eruption lasted 107 days, and now ranks as the most destructive event at Kilauea since 1790, and as one of the most costly volcanic disasters in U.S. history. Multiple simultaneous hazard events unfolded, including sustained seismic activity leading to collapse at the summit of Halema'uma'u crater and severe damage to the HVO facility, with additional eruption of lava in t
Authors
Dee M. Williams, Vic F. Avery, Michelle L. Coombs, Dale A. Cox, Lief R. Horwitz, Sara K. McBride, Ryan J. McClymont, Seth C. Moran
Phase equilibrium of a high-SiO2, andesite at fO2 = RRO: Implications for Augustine volcano and other high-fO2 arc andesites
Understanding the impact of magmatic plumbing systems on explosive volcanic activity is important for hazard management. This study describes phase equilibria experiments using a high-silica andesite (HSA; SiO2 = 62.5 wt%) from the 2006 eruption of Augustine Volcano, Alaska. Experiments were conducted under H2O saturated conditions, f02f02 = RRO (Re–ReO2 or ~ Ni–NiO + 2), at pressures of 50–200 MP
Authors
Sarah H. De Angelis, Jessica F. Larsen, Michelle L. Coombs, James E. P. Utley, Andrew P. Dunn
Petrology of the 2016–2017 eruption of Bogoslof Island
The 2016–2017 eruption of Bogoslof primarily produced crystal-rich amphibole basalts. The dominant juvenile tephra were highly microlitic with diktytaxitic vesicles, and amphiboles had large reaction rims. Both observations support a magma history of slow ascent and/or shallow stalling prior to eruption. Plagioclase-amphibole-clinopyroxene mineralogy are also suggestive of shallow magma crystalliz
Authors
Matthew W. Loewen, Pavel Izbekof, Justin Moshrefzadeh, Michelle L. Coombs, Jessica Larsen, Nathan Graham, Michelle Harbin, Christopher F. Waythomas, Kristi L. Wallace
Overview, chronology, and impacts of the 2016–2017 eruption of Bogoslof volcano, Alaska
The 2016–2017 eruption of Bogoslof volcano, a back-arc shallow submarine volcano in Alaska’s Aleutian arc, began in December 2016 and included 70 explosive events and at least two episodes of subaerial dome building. Because the volcano had no local monitoring stations during the eruption, a combination of distant seismic stations, regional infrasound sensors, lightning detection, a variety of sat
Authors
Michelle L. Coombs, Kristi L. Wallace, Cheryl Cameron, John J. Lyons, Aaron Wech, Kim M. Angeli, Peter Cervelli
On the eruption age and provenance of the Old Crow tephra
Tephrochronology is used to correlate and reconstruct geographically disparate sedimentary records of changing environment, climate, and landscape throughout geologic time. Single tephra layers represent isochronous markers across broad regions, thus accurate and precise radiometric constraints on the timing of eruption are critical to their utility. The Old Crow tephra is found throughout eastern
Authors
Seth D. Burgess, Matthew Coble, Jorge A. Vazquez, Michelle L. Coombs, Kristi L. Wallace
The 2018 rift eruption and summit collapse of Kilauea Volcano
In 2018, Kīlauea Volcano experienced its largest lower East Rift Zone (LERZ) eruption and caldera collapse in at least 200 years. After collapse of the Pu'u 'Ō'ō vent on 30 April, magma propagated downrift. Eruptive fissures opened in the LERZ on 3 May, eventually extending ~6.8 km. A 4 May earthquake (M6.9) produced ~5 m of fault slip. Lava erupted at rates exceeding 100 m3/s, eventually coveri
Authors
Christina A. Neal, Steven Brantley, Loren Antolik, Janet Babb, Matthew K. Burgess, Michael Cappos, Jefferson Chang, Sarah Conway, Liliana Desmither, Peter Dotray, Tamar Elias, Pauline Fukunaga, Steven Fuke, Ingrid Johanson, Kevan Kamibayashi, James P. Kauahikaua, R. Lopaka Lee, S. Pekalib, Asta Miklius, Brian Shiro, Don Swanson, Patricia Nadeau, Michael H. Zoeller, P. Okubo, Carolyn Parcheta, Matthew R. Patrick, William Tollett, Frank A. Trusdell, Edward F. Younger, Emily Montgomery-Brown, Kyle R. Anderson, Michael P. Poland, Jessica L. Ball, Joseph A. Bard, Michelle L. Coombs, Hannah R. Dietterich, Christoph Kern, Weston Thelen, Peter Cervelli, Tim R. Orr, Bruce F. Houghton, Cheryl Gansecki, Richard Hazlett, Paul Lundgren, Angela K. Diefenbach, Allan Lerner, Greg Waite, Peter J. Kelly, Laura E. Clor, Cynthia Werner, Katherine Mulliken, Gary B. Fisher, David Damby
Short-term forecasting and detection of explosions during the 2016–2017 eruption of Bogoslof volcano, Alaska
We describe a multidisciplinary approach to forecast, rapidly detect, and characterize explosive events during the 2016–2017 eruption of Bogoslof volcano, a back-arc shallow submarine volcano in Alaska’s Aleutian arc. The eruptive sequence began in December 2016 and included about 70 discrete explosive events. Because the volcano has no local monitoring stations, we used distant stations on the ne
Authors
Michelle L. Coombs, Aaron Wech, Matthew M. Haney, John J. Lyons, David Schneider, Hans Schwaiger, Kristi L. Wallace, David Fee, Jeffrey T. Freymueller, Janet Schaefer, Gabrielle Tepp
Postglacial eruptive history and geochemistry of Semisopochnoi volcano, western Aleutian Islands, Alaska
Semisopochnoi Island, located in the Rat Islands group of the western Aleutian Islands and Aleutian volcanic arc, is a roughly circular island composed of scattered volcanic vents, the prominent caldera of Semisopochnoi volcano, and older, ancestral volcanic rocks. The oldest rocks on the island are gently radially dipping lavas that are the remnants of a shield volcano and of Ragged Top, which is
Authors
Michelle L. Coombs, Jessica F. Larsen, Christina A. Neal
Amphibole reaction rims as a record of pre-eruptive magmatic heating: An experimental approach
Magmatic minerals record the pre-eruptive timescales of magma ascent and mixing in crustal reservoirs and conduits. Investigations of the mineral records of magmatic processes are fundamental to our understanding of what controls eruption style, as ascent rates and magma mixing processes are well known to control and/or trigger potentially hazardous explosive eruptions. Thus, amphibole reaction ri
Authors
S. H. De Angelis, J. Larsen, Michelle L. Coombs, A. Dunn, Leslie A. Hayden
Science and Products
- Data
Digital geologic map data for Semisopochnoi Island, Alaska
This dataset contains digital data that were used for the creation of a geologic map shown in Figure 3 in USGS SIR 2017-5150; Postglacial Eruptive History and Geochemistry of Semisopochnoi Volcano, Western Aleutian Islands, Alaska by Coombs, M.L. and others. The map shows the generalized geology of the island and the locations of stations occupied during field work conducted in the summer of 2005. - Maps
Geologic map of Mount Gareloi, Gareloi Island, Alaska
Gareloi Island (lat 51.7° N., long 178.8° W.) is located in the Delarof Islands group of the Aleutian Islands, approximately 2,000 km west-southwest of Anchorage and 150 km west of Adak, the westernmost town in Alaska. This small (~8- x 10-km diam), uninhabited island is constructed exclusively of eruptive products from Mount Gareloi volcano, a Pleistocene and Holocene, steep-sided, composite stra - Publications
Filter Total Items: 69
Coordinating science during an eruption: Lessons from the 2020–2021 Kīlauea volcanic eruption
Data collected during well-observed eruptions can lead to dramatic increases in our understanding of volcanic processes. However, the necessary prioritization of public safety and hazard mitigation during a crisis means that scientific opportunities may be sacrificed. Thus, maximizing the scientific gains from eruptions requires improved planning and coordinating science activities among governmenAuthorsKari M. Cooper, Kyle R. Anderson, Kathy Cashman, Michelle L. Coombs, Hannah R. Dietterich, Tobias Fischer, Bruce F. Houghton, Ingrid Johanson, Kendra Lynn, Michael Manga, Christelle WauthierGeneration of calc-alkaline magmas during crystallization at high oxygen fugacity: An experimental and petrologic study of tephras from Buldir Volcano, western Aleutian Arc, Alaska, USA
Despite agreement that calc-alkaline volcanism occurs at subduction zones and is responsible for the genesis of continental landmasses, there is no consensus on the source of the Fe-depleted signature hallmark to calc-alkaline volcanism. In this study, we utilize mafic tephras collected from Buldir Volcano to address the genesis of strongly calc-alkaline volcanic rocks (those with a low TholeiiticAuthorsLaura Waters, Elizabeth Cottrell, Michelle L. Coombs, Katherine A. KelleyThe eruptive history, magmatic evolution, and influence of glacial ice at long-lived Akutan volcano, eastern Aleutian Islands, Alaska, USA
New 40Ar/39Ar and whole-rock geochemical data are used to develop a detailed eruptive chronology for Akutan volcano, Akutan Island, Alaska, USA, in the eastern Aleutian island arc. Akutan Island (166°W, 54.1°N) is the site of long-lived volcanism and the entire island comprises volcanic rocks as old as 3.3 Ma. Our current study is on the 225 km2 western half of the island, where our results show tAuthorsMichelle L. Coombs, Brian JichaU.S. Geological Survey 2018 Kīlauea Volcano eruption response in Hawai'i—After-action review
The 2018 Kīlauea Volcano eruption lasted 107 days, and now ranks as the most destructive event at Kilauea since 1790, and as one of the most costly volcanic disasters in U.S. history. Multiple simultaneous hazard events unfolded, including sustained seismic activity leading to collapse at the summit of Halema'uma'u crater and severe damage to the HVO facility, with additional eruption of lava in tAuthorsDee M. Williams, Vic F. Avery, Michelle L. Coombs, Dale A. Cox, Lief R. Horwitz, Sara K. McBride, Ryan J. McClymont, Seth C. MoranPhase equilibrium of a high-SiO2, andesite at fO2 = RRO: Implications for Augustine volcano and other high-fO2 arc andesites
Understanding the impact of magmatic plumbing systems on explosive volcanic activity is important for hazard management. This study describes phase equilibria experiments using a high-silica andesite (HSA; SiO2 = 62.5 wt%) from the 2006 eruption of Augustine Volcano, Alaska. Experiments were conducted under H2O saturated conditions, f02f02 = RRO (Re–ReO2 or ~ Ni–NiO + 2), at pressures of 50–200 MPAuthorsSarah H. De Angelis, Jessica F. Larsen, Michelle L. Coombs, James E. P. Utley, Andrew P. DunnPetrology of the 2016–2017 eruption of Bogoslof Island
The 2016–2017 eruption of Bogoslof primarily produced crystal-rich amphibole basalts. The dominant juvenile tephra were highly microlitic with diktytaxitic vesicles, and amphiboles had large reaction rims. Both observations support a magma history of slow ascent and/or shallow stalling prior to eruption. Plagioclase-amphibole-clinopyroxene mineralogy are also suggestive of shallow magma crystallizAuthorsMatthew W. Loewen, Pavel Izbekof, Justin Moshrefzadeh, Michelle L. Coombs, Jessica Larsen, Nathan Graham, Michelle Harbin, Christopher F. Waythomas, Kristi L. WallaceOverview, chronology, and impacts of the 2016–2017 eruption of Bogoslof volcano, Alaska
The 2016–2017 eruption of Bogoslof volcano, a back-arc shallow submarine volcano in Alaska’s Aleutian arc, began in December 2016 and included 70 explosive events and at least two episodes of subaerial dome building. Because the volcano had no local monitoring stations during the eruption, a combination of distant seismic stations, regional infrasound sensors, lightning detection, a variety of satAuthorsMichelle L. Coombs, Kristi L. Wallace, Cheryl Cameron, John J. Lyons, Aaron Wech, Kim M. Angeli, Peter CervelliOn the eruption age and provenance of the Old Crow tephra
Tephrochronology is used to correlate and reconstruct geographically disparate sedimentary records of changing environment, climate, and landscape throughout geologic time. Single tephra layers represent isochronous markers across broad regions, thus accurate and precise radiometric constraints on the timing of eruption are critical to their utility. The Old Crow tephra is found throughout easternAuthorsSeth D. Burgess, Matthew Coble, Jorge A. Vazquez, Michelle L. Coombs, Kristi L. WallaceThe 2018 rift eruption and summit collapse of Kilauea Volcano
In 2018, Kīlauea Volcano experienced its largest lower East Rift Zone (LERZ) eruption and caldera collapse in at least 200 years. After collapse of the Pu'u 'Ō'ō vent on 30 April, magma propagated downrift. Eruptive fissures opened in the LERZ on 3 May, eventually extending ~6.8 km. A 4 May earthquake (M6.9) produced ~5 m of fault slip. Lava erupted at rates exceeding 100 m3/s, eventually coveriAuthorsChristina A. Neal, Steven Brantley, Loren Antolik, Janet Babb, Matthew K. Burgess, Michael Cappos, Jefferson Chang, Sarah Conway, Liliana Desmither, Peter Dotray, Tamar Elias, Pauline Fukunaga, Steven Fuke, Ingrid Johanson, Kevan Kamibayashi, James P. Kauahikaua, R. Lopaka Lee, S. Pekalib, Asta Miklius, Brian Shiro, Don Swanson, Patricia Nadeau, Michael H. Zoeller, P. Okubo, Carolyn Parcheta, Matthew R. Patrick, William Tollett, Frank A. Trusdell, Edward F. Younger, Emily Montgomery-Brown, Kyle R. Anderson, Michael P. Poland, Jessica L. Ball, Joseph A. Bard, Michelle L. Coombs, Hannah R. Dietterich, Christoph Kern, Weston Thelen, Peter Cervelli, Tim R. Orr, Bruce F. Houghton, Cheryl Gansecki, Richard Hazlett, Paul Lundgren, Angela K. Diefenbach, Allan Lerner, Greg Waite, Peter J. Kelly, Laura E. Clor, Cynthia Werner, Katherine Mulliken, Gary B. Fisher, David DambyShort-term forecasting and detection of explosions during the 2016–2017 eruption of Bogoslof volcano, Alaska
We describe a multidisciplinary approach to forecast, rapidly detect, and characterize explosive events during the 2016–2017 eruption of Bogoslof volcano, a back-arc shallow submarine volcano in Alaska’s Aleutian arc. The eruptive sequence began in December 2016 and included about 70 discrete explosive events. Because the volcano has no local monitoring stations, we used distant stations on the neAuthorsMichelle L. Coombs, Aaron Wech, Matthew M. Haney, John J. Lyons, David Schneider, Hans Schwaiger, Kristi L. Wallace, David Fee, Jeffrey T. Freymueller, Janet Schaefer, Gabrielle TeppPostglacial eruptive history and geochemistry of Semisopochnoi volcano, western Aleutian Islands, Alaska
Semisopochnoi Island, located in the Rat Islands group of the western Aleutian Islands and Aleutian volcanic arc, is a roughly circular island composed of scattered volcanic vents, the prominent caldera of Semisopochnoi volcano, and older, ancestral volcanic rocks. The oldest rocks on the island are gently radially dipping lavas that are the remnants of a shield volcano and of Ragged Top, which isAuthorsMichelle L. Coombs, Jessica F. Larsen, Christina A. NealAmphibole reaction rims as a record of pre-eruptive magmatic heating: An experimental approach
Magmatic minerals record the pre-eruptive timescales of magma ascent and mixing in crustal reservoirs and conduits. Investigations of the mineral records of magmatic processes are fundamental to our understanding of what controls eruption style, as ascent rates and magma mixing processes are well known to control and/or trigger potentially hazardous explosive eruptions. Thus, amphibole reaction riAuthorsS. H. De Angelis, J. Larsen, Michelle L. Coombs, A. Dunn, Leslie A. Hayden - 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