Michelle L. Coombs, Ph.D.
Michelle Coombs is a Supervisory Research Geologist with the U.S. Geological Survey Volcanic Science Center. At the Alaska Volcano Observatory, she works on a wide variety of topics related to active volcanism, volcano geology, and volcanic hazards. She also serves as chief of the Volcano Hazards Assessment Project.
Professional Experience
2023–present: Supervisory Research Geologist, Alaska Volcano Observatory, Volcano Science Center, U.S. Geological Survey, Anchorage, AK
2016–2023: Scientist-in-Charge, Alaska Volcano Observatory
2004–2016: Research Geologist, Alaska Volcano Observatory
2001–2004: Research Geologist, Volcano Hazards Team, U.S. Geological Survey, Menlo Park CA
Education and Certifications
B.A., Geology, Williams College, 1994
Ph.D., Geology, University of Alaska Fairbanks, 2001
Science and Products
Filter Total Items: 79
The 2006 eruption of Augustine Volcano, Alaska The 2006 eruption of Augustine Volcano, Alaska
Augustine Volcano, the most historically active volcano in Alaska’s Cook Inlet region, again showed signs of life in April 2005. Escalating seismic unrest, ground deformation, and gas emissions culminated in an eruption from January 11 to mid-March of 2006, the fifth major eruption in 75 years. The eruption began with a series of 13 short-lived blasts over 20 days that sent pyroclastic...
Preliminary Volcano-Hazard Assessment for Gareloi Volcano, Gareloi Island, Alaska Preliminary Volcano-Hazard Assessment for Gareloi Volcano, Gareloi Island, Alaska
Gareloi Volcano (178.794 degrees W and 51.790 degrees N) is located on Gareloi Island in the Delarof Islands group of the Aleutian Islands, about 2,000 kilometers west-southwest of Anchorage and about 150 kilometers west of Adak, the westernmost community in Alaska. This small (about 8x10 kilometer) volcano has been one of the most active in the Aleutians since its discovery by the...
Authors
Michelle L. Coombs, Robert G. McGimsey, Brandon L. Browne
Preliminary volcano-hazard assessment for the Tanaga volcanic cluster, Tanaga Island, Alaska Preliminary volcano-hazard assessment for the Tanaga volcanic cluster, Tanaga Island, Alaska
Summary of Volcano Hazards at Tanaga Volcanic Cluster The Tanaga volcanic cluster lies on the northwest part of Tanaga Island, about 100 kilometers west of Adak, Alaska, and 2,025 kilometers southwest of Anchorage, Alaska. The cluster consists of three volcanoes-from west to east, they are Sajaka, Tanaga, and Takawangha. All three volcanoes have erupted in the last 1,000 years, producing...
Authors
Michelle L. Coombs, Robert G. McGimsey, Brandon L. Browne
Massive edifice failure at Aleutian arc volcanoes Massive edifice failure at Aleutian arc volcanoes
Along the 450-km-long stretch of the Aleutian volcanic arc from Great Sitkin to Kiska Islands, edifice failure and submarine debris-avalanche deposition have occurred at seven of ten Quaternary volcanic centers. Reconnaissance geologic studies have identified subaerial evidence for large-scale prehistoric collapse events at five of the centers (Great Sitkin, Kanaga, Tanaga, Gareloi, and...
Authors
Michelle L. Coombs, S.M. White, D.W. Scholl
Geothermal disruption of summit glaciers at Mount Spurr Volcano, 2004-6: An unusual manifestation of volcanic unrest Geothermal disruption of summit glaciers at Mount Spurr Volcano, 2004-6: An unusual manifestation of volcanic unrest
Mount Spurr, a 3,374-m-high stratovolcano in the Cook Inlet region of Alaska, showed signs of volcanic unrest beginning in 2004 and lasting through 2006. These signs included increases in heat flow, seismicity, and gas flux, which we interpret as the results of a magmatic intrusion in mid-2004. In response, debris-laden meltwater beneath the glacier in Mount Spurr's geothermally active...
Authors
Michelle L. Coombs, Christina A. Neal, Rick L. Wessels, Robert G. McGimsey
Studies by the U.S. Geological Survey in Alaska, 2005 Studies by the U.S. Geological Survey in Alaska, 2005
Authors
David W. Houseknecht, Kenneth J. Bird, Michelle L. Coombs, Christina A. Neal, Rick L. Wessels, Robert G. McGimsey, John F. Slack, W.C. Pat Shanks, Susan M. Karl, Pamela A. Gemery, Peter E. Bittenbender, W. Ian Ridley, W. Matthew Burns, Daniel O. Hayba, Elisabeth L. Rowan, Robert A. Ayuso, Peter J. Haeussler, Gregory A. Wandless, Anna Colvin
The reawakening of Alaska's Augustine volcano The reawakening of Alaska's Augustine volcano
Augustine volcano, in south central Alaska, ended a 20-year period of repose on 11 January 2006 with 13 explosive eruptions in 20 days. Explosive activity shifted to a quieter effusion of lava in early February, forming a new summit lava dome and two short, blocky lava flows by late March (Figure 1). The eruption was heralded by eight months of increasing seismicity, deformation, gas...
Authors
John A. Power, Christopher J. Nye, Michelle L. Coombs, Rick L. Wessels, Peter F. Cervelli, Jon Dehn, Kristi L. Wallace, Jeffrey T. Freymueller, Michael P. Doukas
Growth and collapse of Hawaiian volcanoes Growth and collapse of Hawaiian volcanoes
This special issue is an outgrowth of a session of the same name held at the 2003 Fall Meeting of the American Geophysical Union (AGU) in San Francisco. The session served dual purposes: to highlight recent advances in our understanding of the development and internal structure of Hawaiian volcanoes, and to recognize the important contributions of James Moore to this field of study.
Authors
Michelle L. Coombs, Barry W. Eakins, Peter F. Cervelli
Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts
Major-element and volatile (H2O, CO2, S) compositions of glasses from the submarine flanks of Kilauea Volcano record its growth from pre-shield into tholeiite shield-stage. Pillow lavas of mildly alkalic basalt at 2600–1900 mbsl on the upper slope of the south flank are an intermediate link between deeper alkalic volcaniclastics and the modern tholeiite shield. Lava clast glasses from...
Authors
Michelle L. Coombs, Thomas W. Sisson, Peter W. Lipman
Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa
Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from them document early underwater growth of...
Authors
Peter W. Lipman, Thomas W. Sisson, Michelle L. Coombs, Andrew T. Calvert, Jun-Ichi Kimura
Submarine sliver in North Kona: A window into the early magmatic and growth history of Hualalai Volcano, Hawaii Submarine sliver in North Kona: A window into the early magmatic and growth history of Hualalai Volcano, Hawaii
Two manned submersible dives examined the Hualalai Northwest rift zone and an elongate ridge cresting at 3900 mbsl during a 2002 JAMSTEC cruise. The rift zone flank at dive site S690 (water depth 3412–2104 m) is draped by elongated and truncated pillow lavas. These olivine-rich tholeiitic lavas are compositionally indistinguishable from those examined further south along the bench...
Authors
Julia E. Hammer, Michelle L. Coombs, Patrick J. Shamberger, Jun-Ichi Kimura
Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component
Submarine lavas recovered from the Hilina bench region, offshore Kilauea, Hawaii Island provide information on ancient Kilauea volcano and the geochemical components of the Hawaiian hotspot. Alkalic lavas, including nephelinite, basanite, hawaiite, and alkali basalt, dominate the earliest stage of Kilauea magmatism. Transitional basalt pillow lavas are an intermediate phase, preceding...
Authors
Jun-Ichi Kimura, Thomas W. Sisson, Natsuko Nakano, Michelle L. Coombs, Peter W. Lipman
Science and Products
Filter Total Items: 79
The 2006 eruption of Augustine Volcano, Alaska The 2006 eruption of Augustine Volcano, Alaska
Augustine Volcano, the most historically active volcano in Alaska’s Cook Inlet region, again showed signs of life in April 2005. Escalating seismic unrest, ground deformation, and gas emissions culminated in an eruption from January 11 to mid-March of 2006, the fifth major eruption in 75 years. The eruption began with a series of 13 short-lived blasts over 20 days that sent pyroclastic...
Preliminary Volcano-Hazard Assessment for Gareloi Volcano, Gareloi Island, Alaska Preliminary Volcano-Hazard Assessment for Gareloi Volcano, Gareloi Island, Alaska
Gareloi Volcano (178.794 degrees W and 51.790 degrees N) is located on Gareloi Island in the Delarof Islands group of the Aleutian Islands, about 2,000 kilometers west-southwest of Anchorage and about 150 kilometers west of Adak, the westernmost community in Alaska. This small (about 8x10 kilometer) volcano has been one of the most active in the Aleutians since its discovery by the...
Authors
Michelle L. Coombs, Robert G. McGimsey, Brandon L. Browne
Preliminary volcano-hazard assessment for the Tanaga volcanic cluster, Tanaga Island, Alaska Preliminary volcano-hazard assessment for the Tanaga volcanic cluster, Tanaga Island, Alaska
Summary of Volcano Hazards at Tanaga Volcanic Cluster The Tanaga volcanic cluster lies on the northwest part of Tanaga Island, about 100 kilometers west of Adak, Alaska, and 2,025 kilometers southwest of Anchorage, Alaska. The cluster consists of three volcanoes-from west to east, they are Sajaka, Tanaga, and Takawangha. All three volcanoes have erupted in the last 1,000 years, producing...
Authors
Michelle L. Coombs, Robert G. McGimsey, Brandon L. Browne
Massive edifice failure at Aleutian arc volcanoes Massive edifice failure at Aleutian arc volcanoes
Along the 450-km-long stretch of the Aleutian volcanic arc from Great Sitkin to Kiska Islands, edifice failure and submarine debris-avalanche deposition have occurred at seven of ten Quaternary volcanic centers. Reconnaissance geologic studies have identified subaerial evidence for large-scale prehistoric collapse events at five of the centers (Great Sitkin, Kanaga, Tanaga, Gareloi, and...
Authors
Michelle L. Coombs, S.M. White, D.W. Scholl
Geothermal disruption of summit glaciers at Mount Spurr Volcano, 2004-6: An unusual manifestation of volcanic unrest Geothermal disruption of summit glaciers at Mount Spurr Volcano, 2004-6: An unusual manifestation of volcanic unrest
Mount Spurr, a 3,374-m-high stratovolcano in the Cook Inlet region of Alaska, showed signs of volcanic unrest beginning in 2004 and lasting through 2006. These signs included increases in heat flow, seismicity, and gas flux, which we interpret as the results of a magmatic intrusion in mid-2004. In response, debris-laden meltwater beneath the glacier in Mount Spurr's geothermally active...
Authors
Michelle L. Coombs, Christina A. Neal, Rick L. Wessels, Robert G. McGimsey
Studies by the U.S. Geological Survey in Alaska, 2005 Studies by the U.S. Geological Survey in Alaska, 2005
Authors
David W. Houseknecht, Kenneth J. Bird, Michelle L. Coombs, Christina A. Neal, Rick L. Wessels, Robert G. McGimsey, John F. Slack, W.C. Pat Shanks, Susan M. Karl, Pamela A. Gemery, Peter E. Bittenbender, W. Ian Ridley, W. Matthew Burns, Daniel O. Hayba, Elisabeth L. Rowan, Robert A. Ayuso, Peter J. Haeussler, Gregory A. Wandless, Anna Colvin
The reawakening of Alaska's Augustine volcano The reawakening of Alaska's Augustine volcano
Augustine volcano, in south central Alaska, ended a 20-year period of repose on 11 January 2006 with 13 explosive eruptions in 20 days. Explosive activity shifted to a quieter effusion of lava in early February, forming a new summit lava dome and two short, blocky lava flows by late March (Figure 1). The eruption was heralded by eight months of increasing seismicity, deformation, gas...
Authors
John A. Power, Christopher J. Nye, Michelle L. Coombs, Rick L. Wessels, Peter F. Cervelli, Jon Dehn, Kristi L. Wallace, Jeffrey T. Freymueller, Michael P. Doukas
Growth and collapse of Hawaiian volcanoes Growth and collapse of Hawaiian volcanoes
This special issue is an outgrowth of a session of the same name held at the 2003 Fall Meeting of the American Geophysical Union (AGU) in San Francisco. The session served dual purposes: to highlight recent advances in our understanding of the development and internal structure of Hawaiian volcanoes, and to recognize the important contributions of James Moore to this field of study.
Authors
Michelle L. Coombs, Barry W. Eakins, Peter F. Cervelli
Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts
Major-element and volatile (H2O, CO2, S) compositions of glasses from the submarine flanks of Kilauea Volcano record its growth from pre-shield into tholeiite shield-stage. Pillow lavas of mildly alkalic basalt at 2600–1900 mbsl on the upper slope of the south flank are an intermediate link between deeper alkalic volcaniclastics and the modern tholeiite shield. Lava clast glasses from...
Authors
Michelle L. Coombs, Thomas W. Sisson, Peter W. Lipman
Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa
Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from them document early underwater growth of...
Authors
Peter W. Lipman, Thomas W. Sisson, Michelle L. Coombs, Andrew T. Calvert, Jun-Ichi Kimura
Submarine sliver in North Kona: A window into the early magmatic and growth history of Hualalai Volcano, Hawaii Submarine sliver in North Kona: A window into the early magmatic and growth history of Hualalai Volcano, Hawaii
Two manned submersible dives examined the Hualalai Northwest rift zone and an elongate ridge cresting at 3900 mbsl during a 2002 JAMSTEC cruise. The rift zone flank at dive site S690 (water depth 3412–2104 m) is draped by elongated and truncated pillow lavas. These olivine-rich tholeiitic lavas are compositionally indistinguishable from those examined further south along the bench...
Authors
Julia E. Hammer, Michelle L. Coombs, Patrick J. Shamberger, Jun-Ichi Kimura
Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component
Submarine lavas recovered from the Hilina bench region, offshore Kilauea, Hawaii Island provide information on ancient Kilauea volcano and the geochemical components of the Hawaiian hotspot. Alkalic lavas, including nephelinite, basanite, hawaiite, and alkali basalt, dominate the earliest stage of Kilauea magmatism. Transitional basalt pillow lavas are an intermediate phase, preceding...
Authors
Jun-Ichi Kimura, Thomas W. Sisson, Natsuko Nakano, Michelle L. Coombs, Peter W. Lipman