Michelle L. Coombs, Ph.D.
Michelle Coombs is a Research Geologist with the U.S. Geological Survey Volcanic Science Center. She served as Scientist-in-Charge of the Alaska Volcano Observatory from 2016-2023. 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
2016–2023: Scientist-in-Charge, Alaska Volcano Observatory, Volcano Science Center, U.S. Geological Survey, Anchorage, AK
2004–Present: 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
Filter Total Items: 78
High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption of Redoubt Volcano, Alaska High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption of Redoubt Volcano, Alaska
A combination of satellite and airborne high-resolution visible and thermal infrared (TIR) image data detected and measured changes at Redoubt Volcano during the 2008–2009 unrest and eruption. The TIR sensors detected persistent elevated temperatures at summit ice-melt holes as seismicity and gas emissions increased in late 2008 to March 2009. A phreatic explosion on 15 March was...
Authors
Rick L. Wessels, R. Greg Vaughan, Matthew R. Patrick, Michelle L. Coombs
Volcano–ice interactions precursory to the 2009 eruption of Redoubt Volcano, Alaska Volcano–ice interactions precursory to the 2009 eruption of Redoubt Volcano, Alaska
In late summer of 2008, after nearly 20 years of quiescence, Redoubt Volcano began to show signs of abnormal heat flow in its summit crater. In the months that followed, the excess heat triggered melting and ablation of Redoubt's glaciers, beginning at the summit and propagating to lower elevations as the unrest accelerated. A variety of morphological changes were observed, including the...
Authors
Heather A. Bleick, Michelle L. Coombs, Peter F. Cervelli, Katharine F. Bull, Rick Wessels
Andesites of the 2009 eruption of Redoubt Volcano, Alaska Andesites of the 2009 eruption of Redoubt Volcano, Alaska
Crystal-rich andesites that erupted from Redoubt Volcano in 2009 range from 57.5 to 62.5 wt.% SiO2 and have phenocryst and phenocryst-melt relations consistent with staging in the upper crust. Early explosive products are low-silica andesites (LSA,
Authors
Michelle L. Coombs, Thomas W. Sisson, Heather A. Bleick, Sarah M. Henton, Christopher J. Nye, Allison Payne, Cheryl E. Cameron, Jessica F. Larsen, Kristi L. Wallace, Katharine F. Bull
Pre-eruptive magmatic conditions at Augustine Volcano, Alaska, 2006: Evidence from amphibole geochemistry and textures Pre-eruptive magmatic conditions at Augustine Volcano, Alaska, 2006: Evidence from amphibole geochemistry and textures
Variations in the geochemistry and texture of amphibole phenocrysts erupted from Augustine Volcano in 2006 provide new insights into pre- and syn-eruptive magma storage and mixing. Amphiboles are rare but present in all magma compositions (low- to high-silica andesites) from the 3 month long eruption. Unzoned magnesiohornblende in the high- and low-silica andesites exhibit limited...
Authors
Sarah De Angelis, Jessica D Larsen, Michelle L. Coombs
Geology and 40Ar/39Ar geochronology of the medium- to high-K Tanaga volcanic cluster, western Aleutians Geology and 40Ar/39Ar geochronology of the medium- to high-K Tanaga volcanic cluster, western Aleutians
We used geologic mapping and geochemical data augmented by 40Ar/39Ar dating to establish an eruptive chronology for the Tanaga volcanic cluster in the western Aleutian arc. The Tanaga volcanic cluster is unique in comparison to other central and western Aleutian volcanoes in that it consists of three closely spaced, active, volumetrically significant edifices (Sajaka, Tanaga, and...
Authors
Brian R. Jicha, Michelle L. Coombs, Andrew T. Calvert, Brad S. Singer
Using rocks to reveal the inner workings of magma chambers below volcanoes in Alaska’s National Parks Using rocks to reveal the inner workings of magma chambers below volcanoes in Alaska’s National Parks
Alaska is one of the most vigorously volcanic regions on the planet, and Alaska’s national parks are home to many of the state’s most active volcanoes. These pose both local and more distant hazards in the form of lava and pyroclastic flows, lahars (mudflows), ash clouds, and ash fall. Alaska’s volcanoes lie along the arc of the Aleutian-Alaskan subduction zone, caused as the oceanic...
Authors
Michelle L. Coombs, Charles R. Bacon
The 2009 eruption of Redoubt Volcano, Alaska The 2009 eruption of Redoubt Volcano, Alaska
Redoubt Volcano, an ice-covered stratovolcano on the west side of Cook Inlet, erupted in March 2009 after several months of escalating unrest. The 2009 eruption of Redoubt Volcano shares many similarities with eruptions documented most recently at Redoubt in 1966–68 and 1989–90. In each case, the eruptive phase lasted several months, consisted of multiple ashproducing explosions...
Authors
Katharine F. Bull, Cheryl Cameron, Michelle L. Coombs, Angie Diefenbach, Taryn Lopez, Steve McNutt, Christina A. Neal, Allison Payne, John A. Power, David J. Schneider, William E. Scott, Seth Snedigar, Glenn Thompson, Kristi L. Wallace, Christopher F. Waythomas, Peter Webley, Cynthia A. Werner
Timing, distribution, and volume of proximal products of the 2006 eruption of Augustine Volcano: Chapter 8 in The 2006 eruption of Augustine Volcano, Alaska Timing, distribution, and volume of proximal products of the 2006 eruption of Augustine Volcano: Chapter 8 in The 2006 eruption of Augustine Volcano, Alaska
During and after the 2006 eruption of Augustine Volcano, we compiled a geologic map and chronology of new lava and flowage deposits using observational flights, oblique and aerial photography, infrared imaging, satellite data, and field investigations. After approximately 6 months of precursory activity, the explosive phase of the eruption commenced with two explosions on January 11...
Authors
Michelle L. Coombs, Katharine F. Bull, James W. Vallance, David J. Schneider, Evan E. Thoms, Rick L. Wessels, Robert G. McGimsey
Remote telemetered and time-lapse cameras at Augustine Volcano: Chapter 12 in The 2006 eruption of Augustine Volcano, Alaska Remote telemetered and time-lapse cameras at Augustine Volcano: Chapter 12 in The 2006 eruption of Augustine Volcano, Alaska
Before and during the 2006 eruption of Augustine Volcano, the Alaska Volcano Observatory (AVO) installed a network of telemetered and nontelemetered cameras in Homer, Alaska, and on Augustine Island. On December 1, 2005, a network camera was installed at the Homer Field Station, a University of Alaska Fairbanks Geophysical Institute (UAF/GI) facility on a bluff near Homer, where...
Authors
John Paskievitch, Cyrus Read, Thomas Parker
Timing, distribution, and character of tephra fall from the 2005-2006 eruption of Augustine Volcano: Chaper 9 in The 2006 eruption of Augustine Volcano Timing, distribution, and character of tephra fall from the 2005-2006 eruption of Augustine Volcano: Chaper 9 in The 2006 eruption of Augustine Volcano
The 2005–6 eruption of Augustine Volcano produced tephra-fall deposits during each of four eruptive phases. Late in the precursory phase (December 2005), small phreatic explosions produced small-volume, localized, mostly nonjuvenile tephra. The greatest volume of tephra was produced during the explosive phase (January 11–28, 2006) when 13 discrete Vulcanian explosions generated ash...
Authors
Kristi L. Wallace, Christina A. Neal, Robert G. McGimsey
High-resolution satellite and airborne thermal infrared imaging of the 2006 eruption of Augustine Volcano: Chapter 22 in The 2006 eruption of Augustine Volcano, Alaska High-resolution satellite and airborne thermal infrared imaging of the 2006 eruption of Augustine Volcano: Chapter 22 in The 2006 eruption of Augustine Volcano, Alaska
Thermal infrared (TIR) images provided a timely pre- and syn-eruption record of summit changes, lava flow emplacement, and pyroclastic-flow-deposit distribution during the Alaska Volcano Observatory's (AVO) response to the 2006 eruption of Augustine Volcano. A series of images from both handheld and helicopter mounted forward looking infrared radiometers (FLIR) captured detailed views...
Authors
Rick L. Wessels, Michelle L. Coombs, David J. Schneider, Jonathan Dehn, Michael S. Ramsey
Imaging observations of thermal emissions from Augustine Volcano using a small astronomical camera: Chapter 24 in The 2006 eruption of Augustine Volcano, Alaska Imaging observations of thermal emissions from Augustine Volcano using a small astronomical camera: Chapter 24 in The 2006 eruption of Augustine Volcano, Alaska
Long-exposure visible-light images of Augustine Volcano were obtained using a charge-coupled device (CCD) camera during several nights of the 2006 eruption. The camera was located 105 km away, at Homer, Alaska, yet showed persistent bright emissions from the north flank of the volcano corresponding to steam releases, pyroclastic flows, and rockfalls originating near the summit. The...
Authors
Davis D. Sentman, Stephen R. McNutt, Hans C. Stenbaek-Nielsen, Guy Tytgat, Nicole DeRoin
Science and Products
Filter Total Items: 78
High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption of Redoubt Volcano, Alaska High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption of Redoubt Volcano, Alaska
A combination of satellite and airborne high-resolution visible and thermal infrared (TIR) image data detected and measured changes at Redoubt Volcano during the 2008–2009 unrest and eruption. The TIR sensors detected persistent elevated temperatures at summit ice-melt holes as seismicity and gas emissions increased in late 2008 to March 2009. A phreatic explosion on 15 March was...
Authors
Rick L. Wessels, R. Greg Vaughan, Matthew R. Patrick, Michelle L. Coombs
Volcano–ice interactions precursory to the 2009 eruption of Redoubt Volcano, Alaska Volcano–ice interactions precursory to the 2009 eruption of Redoubt Volcano, Alaska
In late summer of 2008, after nearly 20 years of quiescence, Redoubt Volcano began to show signs of abnormal heat flow in its summit crater. In the months that followed, the excess heat triggered melting and ablation of Redoubt's glaciers, beginning at the summit and propagating to lower elevations as the unrest accelerated. A variety of morphological changes were observed, including the...
Authors
Heather A. Bleick, Michelle L. Coombs, Peter F. Cervelli, Katharine F. Bull, Rick Wessels
Andesites of the 2009 eruption of Redoubt Volcano, Alaska Andesites of the 2009 eruption of Redoubt Volcano, Alaska
Crystal-rich andesites that erupted from Redoubt Volcano in 2009 range from 57.5 to 62.5 wt.% SiO2 and have phenocryst and phenocryst-melt relations consistent with staging in the upper crust. Early explosive products are low-silica andesites (LSA,
Authors
Michelle L. Coombs, Thomas W. Sisson, Heather A. Bleick, Sarah M. Henton, Christopher J. Nye, Allison Payne, Cheryl E. Cameron, Jessica F. Larsen, Kristi L. Wallace, Katharine F. Bull
Pre-eruptive magmatic conditions at Augustine Volcano, Alaska, 2006: Evidence from amphibole geochemistry and textures Pre-eruptive magmatic conditions at Augustine Volcano, Alaska, 2006: Evidence from amphibole geochemistry and textures
Variations in the geochemistry and texture of amphibole phenocrysts erupted from Augustine Volcano in 2006 provide new insights into pre- and syn-eruptive magma storage and mixing. Amphiboles are rare but present in all magma compositions (low- to high-silica andesites) from the 3 month long eruption. Unzoned magnesiohornblende in the high- and low-silica andesites exhibit limited...
Authors
Sarah De Angelis, Jessica D Larsen, Michelle L. Coombs
Geology and 40Ar/39Ar geochronology of the medium- to high-K Tanaga volcanic cluster, western Aleutians Geology and 40Ar/39Ar geochronology of the medium- to high-K Tanaga volcanic cluster, western Aleutians
We used geologic mapping and geochemical data augmented by 40Ar/39Ar dating to establish an eruptive chronology for the Tanaga volcanic cluster in the western Aleutian arc. The Tanaga volcanic cluster is unique in comparison to other central and western Aleutian volcanoes in that it consists of three closely spaced, active, volumetrically significant edifices (Sajaka, Tanaga, and...
Authors
Brian R. Jicha, Michelle L. Coombs, Andrew T. Calvert, Brad S. Singer
Using rocks to reveal the inner workings of magma chambers below volcanoes in Alaska’s National Parks Using rocks to reveal the inner workings of magma chambers below volcanoes in Alaska’s National Parks
Alaska is one of the most vigorously volcanic regions on the planet, and Alaska’s national parks are home to many of the state’s most active volcanoes. These pose both local and more distant hazards in the form of lava and pyroclastic flows, lahars (mudflows), ash clouds, and ash fall. Alaska’s volcanoes lie along the arc of the Aleutian-Alaskan subduction zone, caused as the oceanic...
Authors
Michelle L. Coombs, Charles R. Bacon
The 2009 eruption of Redoubt Volcano, Alaska The 2009 eruption of Redoubt Volcano, Alaska
Redoubt Volcano, an ice-covered stratovolcano on the west side of Cook Inlet, erupted in March 2009 after several months of escalating unrest. The 2009 eruption of Redoubt Volcano shares many similarities with eruptions documented most recently at Redoubt in 1966–68 and 1989–90. In each case, the eruptive phase lasted several months, consisted of multiple ashproducing explosions...
Authors
Katharine F. Bull, Cheryl Cameron, Michelle L. Coombs, Angie Diefenbach, Taryn Lopez, Steve McNutt, Christina A. Neal, Allison Payne, John A. Power, David J. Schneider, William E. Scott, Seth Snedigar, Glenn Thompson, Kristi L. Wallace, Christopher F. Waythomas, Peter Webley, Cynthia A. Werner
Timing, distribution, and volume of proximal products of the 2006 eruption of Augustine Volcano: Chapter 8 in The 2006 eruption of Augustine Volcano, Alaska Timing, distribution, and volume of proximal products of the 2006 eruption of Augustine Volcano: Chapter 8 in The 2006 eruption of Augustine Volcano, Alaska
During and after the 2006 eruption of Augustine Volcano, we compiled a geologic map and chronology of new lava and flowage deposits using observational flights, oblique and aerial photography, infrared imaging, satellite data, and field investigations. After approximately 6 months of precursory activity, the explosive phase of the eruption commenced with two explosions on January 11...
Authors
Michelle L. Coombs, Katharine F. Bull, James W. Vallance, David J. Schneider, Evan E. Thoms, Rick L. Wessels, Robert G. McGimsey
Remote telemetered and time-lapse cameras at Augustine Volcano: Chapter 12 in The 2006 eruption of Augustine Volcano, Alaska Remote telemetered and time-lapse cameras at Augustine Volcano: Chapter 12 in The 2006 eruption of Augustine Volcano, Alaska
Before and during the 2006 eruption of Augustine Volcano, the Alaska Volcano Observatory (AVO) installed a network of telemetered and nontelemetered cameras in Homer, Alaska, and on Augustine Island. On December 1, 2005, a network camera was installed at the Homer Field Station, a University of Alaska Fairbanks Geophysical Institute (UAF/GI) facility on a bluff near Homer, where...
Authors
John Paskievitch, Cyrus Read, Thomas Parker
Timing, distribution, and character of tephra fall from the 2005-2006 eruption of Augustine Volcano: Chaper 9 in The 2006 eruption of Augustine Volcano Timing, distribution, and character of tephra fall from the 2005-2006 eruption of Augustine Volcano: Chaper 9 in The 2006 eruption of Augustine Volcano
The 2005–6 eruption of Augustine Volcano produced tephra-fall deposits during each of four eruptive phases. Late in the precursory phase (December 2005), small phreatic explosions produced small-volume, localized, mostly nonjuvenile tephra. The greatest volume of tephra was produced during the explosive phase (January 11–28, 2006) when 13 discrete Vulcanian explosions generated ash...
Authors
Kristi L. Wallace, Christina A. Neal, Robert G. McGimsey
High-resolution satellite and airborne thermal infrared imaging of the 2006 eruption of Augustine Volcano: Chapter 22 in The 2006 eruption of Augustine Volcano, Alaska High-resolution satellite and airborne thermal infrared imaging of the 2006 eruption of Augustine Volcano: Chapter 22 in The 2006 eruption of Augustine Volcano, Alaska
Thermal infrared (TIR) images provided a timely pre- and syn-eruption record of summit changes, lava flow emplacement, and pyroclastic-flow-deposit distribution during the Alaska Volcano Observatory's (AVO) response to the 2006 eruption of Augustine Volcano. A series of images from both handheld and helicopter mounted forward looking infrared radiometers (FLIR) captured detailed views...
Authors
Rick L. Wessels, Michelle L. Coombs, David J. Schneider, Jonathan Dehn, Michael S. Ramsey
Imaging observations of thermal emissions from Augustine Volcano using a small astronomical camera: Chapter 24 in The 2006 eruption of Augustine Volcano, Alaska Imaging observations of thermal emissions from Augustine Volcano using a small astronomical camera: Chapter 24 in The 2006 eruption of Augustine Volcano, Alaska
Long-exposure visible-light images of Augustine Volcano were obtained using a charge-coupled device (CCD) camera during several nights of the 2006 eruption. The camera was located 105 km away, at Homer, Alaska, yet showed persistent bright emissions from the north flank of the volcano corresponding to steam releases, pyroclastic flows, and rockfalls originating near the summit. The...
Authors
Davis D. Sentman, Stephen R. McNutt, Hans C. Stenbaek-Nielsen, Guy Tytgat, Nicole DeRoin
*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