Michelle Coombs, Ph.D.
Biography
I have been a Research Geologist for USGS-AVO in Anchorage since 2004, and Scientist-in-Charge here since 2016. My current interests include improving observatory responses during eruptions, understanding magmatic systems, and elucidating eruptive histories of volcanoes. I've performed geologic studies throughout the Aleutian-Alaskan subduction zone, from Buldir in the western Aleutians to Hayes and Suprr volcanoes in the Cook Inlet region.
Prior to 2004, I worked for the USGS in Menlo Park, CA, where I studied the geochemistry, petrology, and submarine geology of Hawaiian volcanoes.
POSITIONS
- 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
EDUCATION
- Williams College, BA Geology, 1994
- University of Alaska Fairbanks, PhD Geology, 2001
Publications:
47. De Angelis, S.H., Larsen, J.F., Coombs, M.L., Dunn, A., and Hayden, L., accepted, Storage conditions for high-silica andesite of the 2006 eruption of Augustine Volcano, Alaska: Contributions to Mineraology and Petrology.
46. Loewen, M., Izbekov, P., Moshrefzadeh, J., Coombs, M., Larsen, J., Graham, N., Harbin, M., Waythomas, C., and Wallace, K., 2019, Petrology of the 2016–2017 eruption of Bogoslof Island, Alaska: Bulletin of Volcanology. In Press
45. Coombs, M.L., Wallace, K., Cameron, C.E., Lyons, J.J., Wech, A., Angeli, K., and Cervelli, P., 2019, Overview, chronology, and impacts of the 2016–2017 eruption of Bogoslof volcano, Alaska: Bulletin of Volcanology. 10.1007/s00445-019-1322-9
44. Burgess, S.D., Coble, M.A., Vazquez, J.A., Coombs, M.L., and Wallace, K.L., 2019, On the eruption age and provenance of the Old Crow tephra: Quaternary Science Reviews, 207, 64-79, doi.org/10.1016/j.quascirev.2018.12.026
43. Neal, C.A., Brantley, S.R., Antolik, L., Babb, J., Burgess, M., Calles, K., Cappos, M., Chang, J.C., Conway, S., Desmither, L., Dotray, P., Elias, T., Fukunaga, P., Fuke, S., Johanson, I.A., Kamibayashi, K., Kauahikaua, J., Lee, R.L., Pekalib, S., Miklius, A., Million, W., Moniz, C.J., Nadeau, P.A., Okubo, P., Parcheta, C., Patrick, M.P., Shiro, B., Swanson, D.A., Tollett, W., Trusdell, F., Younger, E.F., Zoeller, M.H., Montgomery-Brown, E.K., Anderson, K.R., Poland, M.P., Ball, J., Bard, J., Coombs, M,, Dietterich, H.R., Kern, C., Thelen, W.A., Cervelli, P.F., Orr, T., Houghton, B.F., Gansecki, C., Hazlett, R., Lundgren, P., Diefenbach, A.K., Lerner, A.H., Waite, G., Kelly, P., Clor, L., Werner, C., Mulliken, K., Fisher, G., 2019, The 2018 rift eruption and summit collapse of Kīlauea Volcano: Science, DOI: 10.1126/science.aav7046. volume 363, p. 367-374.
42. Coombs, M.L., Wech, A., Haney, M.M., Lyons, J.J., Schneider, D.J., Schwaiger, H., Wallace, K., Fee, D., Freymueller, J., Schaefer, J., and Tepp, G., 2018, Short-term forecasting and detection of explosions during the 2016–2017 eruption of Bogoslof volcano, Alaska: Frontiers Earth Science. doi: 10.3389/feart.2018.00122
41. Cameron, C.E., Prejean, S., Coombs, M.L., Wallace, K., Power, J., and Roman, D., 2018, Alaska Volcano Observatory alert and forecasting timeliness: 1989-2017: Frontiers in Earth Science, doi.org/10.3389/feart.2018.00086
40. Coombs, M.L., Larsen, J.F., and Neal., C.A., 2018, Postglacial eruptive history and geochemistry of Semisopochnoi Island, western Aleutian Islands, Alaska: USGS Scientific Investigations Report 2017-51500. doi: 10.3133/sir20175150
39. De Angelis, S.H., Larsen, J.F., Coombs, M.L., Dunn, A., and Hayden, L., 2015, Amphibole reaction rims as a record of pre-eruptive magmatic heating: An experimental approach: Earth and Planetary Science Letters, v. 426, p. 235‒245.
38. Coombs, M.L., and Vazquez, J., 2014, Cogenetic late Pleistocene rhyolite and cumulate diorites from Augustine Volcano revealed by SIMS 238U-230Th dating of zircon, and implications for silicic magma generation by extraction from mush: Geochemistry, Geophysics, Geosystems, v. 15, doi:10.1002/2014GC005589.
37. Wallace, K., Coombs, M.L., Hayden, L., and Waythomas, C., 2014, Insights from a proximal stratigraphic sequence from Hayes Volcano, southcentral Alaska, U.S. Geological Survey Scientific Investigations Report 2014-5133, 32 p., http://pubs.usgs.gov/sir/2014/5133/
36. De Angelis, S., Larsen, J., and Coombs, M.L., 2013, Pre-eruptive magmatic conditions at Augustine Volcano, 2006: Evidence from amphibole geochemistry and textures: Journal of Petrology, v. 54, p. 1939‒1961.
35. Wessels, R.L., Vaughan, R.G., Patrick, M., and Coombs, M.L., 2013, High-resolution satellite and airborne thermal infrared imaging of precursory unrest and 2009 eruption at Redoubt Volcano, Alaska: Journal of Volcanology and Geothermal Research, v. 259, p. 248‒269.
34. Wallace, K.W., Schaefer, J., and Coombs, M.L., 2013, Character, mass distribution, and origin of tephra-fall deposits from the 2009 eruption of Redoubt Volcano, Alaska—Highlighting the significance of particle aggregation: Journal of Volcanology and Geothermal Research, v. 259, p. 145‒169.
33. Bleick, H., Coombs, M.L., Cervelli, P.F., Bull, K.F., and Wessels, R.L., 2013, Volcano-ice interactions precursory to the 2009 eruption of Redoubt Volcano, Alaska: Journal of Volcanology and Geothermal Research, v. 259, p. 373‒388.
32. Coombs, M.L., Sisson, T.W., Bleick, H., Henton, S., Nye, C.J., Payne, A., Cameron, C., Larsen, J.F., Wallace, K., and Bull, K.F., 2013, Andesites of the 2009 eruption of Redoubt Volcano, Alaska: Journal of Volcanology and Geothermal Research, v. 259, p. 349‒372.
31. Coombs, M.L., and Bacon, C.R., 2012, Using rocks to reveal the inner workings of magma chambers below volcanoes in Alaska’s National Parks: Alaska Park Science vol. 11, p. 27-33. Link.
30. Jicha, B.R., Coombs, M.L., Calvert, A.T., and Singer, B.S., 2012, Geology and 40Ar/39Ar geochronology of the medium- to high-K Tanaga volcanic cluster, western Aleutians: Geological Society of America Bulletin, v. 124, p. 842‒856.
29. Coombs, M.L., McGimsey, R.G., and Browne, B.L., 2011, Geologic map of Mount Gareloi, Alaska: U.S. Geological Survey Scientific Investigations Map 3145.
28. Wessels, R.L., Coombs, M.L., Schneider, D.J., Dehn, J., and Ramsey, M.S., 2010, High-resolution satellite and airborne thermal infrared imaging of the 2006 eruption of Augustine Volcano, in Power, J.A., Coombs, M.L., and Freymueller, J.T., eds., The 2006 eruption of Augustine Volcano, Alaska: U.S. Geological Survey Professional Paper 1769, 527–552.
27. Webster, J.D., Mandeville, C.W., Goldoff, B., Coombs, M.L., and Tappen, C., 2010, Augustine Volcano—The influence of volatile components in magmas erupted A.D. 2006 to 2,100 Years Before Present, in Power, J.A., Coombs, M.L., and Freymueller, J.T., eds., The 2006 eruption of Augustine Volcano, Alaska: U.S. Geological Survey Professional Paper 1769, 383–423.
26. Vallance, J.W., Bull, K.F., and Coombs, M.L., 2010, Pyroclastic flows, lahars, and mixed avalanches generated during the 2006 eruption of Augustine Volcano, in Power, J.A., Coombs, M.L., and Freymueller, J.T., eds., The 2006 eruption of Augustine Volcano, Alaska: U.S. Geological Survey Professional Paper 1769, p. 219–267.
25. Larsen, J.F., Nye, C.J., Coombs, M.L., Tilman, M., Izbekov, P., and Cameron, C., 2010, Petrology and geochemistry of the 2006 eruption of Augustine Volcano, in Power, J.A., Coombs, M.L., and Freymueller, J.T., eds., The 2006 eruption of Augustine Volcano, Alaska: U.S. Geological Survey Professional Paper 1769, p. 335–382.
24. Coombs, M.L., Bull, K.F., Vallance, J.W., Schneider, D.J., Thoms, E.E., Wessels, R., and McGimsey, R.G., 2010, Timing, distribution, and volume of proximal products of the 2006 eruption of Augustine Volcano, Alaska, in Power, J.A., Coombs, M.L., and Freymueller, J., eds., The 2006 eruption of Augustine Volcano, Alaska: U.S.G.S. Professional Paper 1769, p. 145–185, 1 plate.
23. Power, J.A., Coombs, M.L., and Freymueller, J., eds., 2010, The 2006 eruption of Augustine Volcano, Alaska: U.S.G.S. Professional Paper 1769, 663 p, 1 plate. Available online (as are the following chapters) at http://pubs.usgs.gov/pp/1769/index.html
22. Sisson, T.W., Kimura, J.-I., and Coombs, M.L., 2009, Basanite–nephelinite suite from early Kilauea: carbonated melts of phlogopite-garnet peridotite at Hawaii’s leading magmatic edge: Contributions to Mineralogy and Petrology, v. 158, p. 803–829
21. Coombs, M.L., McGimsey, R.G., and Browne, B.L., 2008, Preliminary volcano-hazard assessment for Gareloi Volcano, Gareloi Island, Alaska: U.S. Geological Survey Scientific Investigations Report 2008-5159, 36 p., 1 plate. http://pubs.usgs.gov/sir/2008/5159/
20. Coombs, M.L., McGimsey, R.G., and Browne, B.L., 2007, Preliminary volcanic-hazard assessment for the Tanaga volcanic cluster, Alaska: U.S. Geological Survey Scientific Investigations Report 2007-5094, 36 p., 1 plate. http://pubs.usgs.gov/sir/2007/5094/
19. Coombs, M.L., White, S., and Scholl, D., 2007, Massive edifice failure at Aleutian arc volcanoes: Earth and Planetary Science Letters, v. 256, p. 403–418.
18. Coombs, M.L., Neal, C.A., Wessels, R.L., and McGimsey, R.G., 2006, Geothermal disruption of summit glaciers at Mount Spurr Volcano, 2004-6: An unusual manifestation of volcanic unrest, in Haeussler, Peter J., and Galloway, John P., Studies by the U.S. Geological Survey in Alaska, 2005: U.S. Geological Survey Professional Paper 1732-B, 33 p. [available at URL http://pubs.usgs.gov/pp/pp1732/pp1732b/ ]
17. Power, J., Nye, C.J., Coombs, M.L., Wessels, R.L., Cervelli, P.F., Dehn, J., Wallace, K.L., Freymuller, J.T., Doukas, M.P., 2006, The reawakening of Alaska’s Augustine Volcano. Eos, v. 87, p. 373, 374.
16. Lipman, P., Sisson, T., Coombs, M., and Kimura, J.-I., 2006, Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa: Journal of Volcanology and Geothermal Research, v. 151, p. 73–108.
15. Lipman, P., and Coombs, M., 2006, Submarine slump failure during the early(?) tholeiitic shield stage of a Hawaiian volcano: North Kona flank of Hualalai: Journal of Volcanology and Geothermal Research, v. 151, p. 189–216.
14. Kimura, J.-I., Sisson, T.W., Nakano, N., Coombs, M., and Lipman, P., 2006, Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component: Journal of Volcanology and Geothermal Research, v. 151, p. 51–72.
13. Hammer, J., Coombs, M., Shamberger, P., and Kimura, J.-I., 2006, Submarine sliver in North Kona: A window into the early magmatic and growth history of Hualalai Volcano, Hawaii: Journal of Volcanology and Geothermal Research, v. 151, 157–188.
12. Coombs, M., Sisson, T., and Lipman, P., 2006, Growth history of Kilauea inferred from volatile concentrations in submarine-collected basalts: Journal of Volcanology and Geothermal Research, v. 151, p. 19–49.
11. Coombs, M.L., Eakins, B.W., and Cervelli, P.F. (eds.), 2006, Growth and collapse of Hawaiian volcanoes: Journal of Volcanology and Geothermal Research, v. 151, 317 p.
10. Coombs, M., Sisson, T., and Lipman, P., 2004, Major-element, sulfur, and chlorine compositions of glasses from the submarine flank of Kilauea Volcano, Hawaii, collected during 1998-2002 Japan Marine Science and Technology Center cruises: U.S.G.S. Open-File Report 2004-1378.
9. Coombs, M., Clague, D., Moore, G., and Cousens, B., 2004, The growth and collapse of Waianae volcano, Hawaii, as revealed by exploration of its submarine flanks: Geochemistry, Geophysics, Geosystems, v. 5, doi: 10.1029/2004GC000717.
8. Coombs, M., and Gardner, J., 2004, Reaction rim growth on olivine in silicic melt: Implications for magma mixing: American Mineralogist, v. 89, p. 748–759
7. Coombs, M., Sisson, T., and Kimura, J.-I., 2004, Ultra-high chlorine in submarine Kilauea glasses: Evidence for assimilation of brine by magma: Earth and Planetary Science Letters, v. 217, p. 297–313.
6. Coombs, M., Eichelberger, J., and Rutherford, M., 2003, Experimental and textural constraints on mafic enclave formation in volcanic rocks: Journal of Volcanology and Geothermal Research, v. 119, p. 125–144.
5. Coombs, M., and Gardner, J., 2001, Shallow storage conditions for the rhyolite of the 1912 eruption of Katmai, Alaska: Geology, v. 29, p. 775–778.
4. Coombs, M., 2001, Experimental and petrologic constraints on magma movement, storage, and interactions at two volcanoes in Katmai National Park, Alaska: Fairbanks, University of Alaska, Ph.D. thesis, 214 p.
3. Coombs, M., Eichelberger, J., and Rutherford, M., 2000, Magma storage and mixing conditions for the 1953-1968 eruption of Southwest Trident volcano, Katmai National Park, Alaska: Contributions to Mineralogy and Petrology, v. 140, p. 99–118.
2. Miller, T., Chertkoff, D., Eichelberger, J., and Coombs, M., 1999, Mount Dutton volcano, Alaska: Aleutian Arc analog to Unzen Volcano, Japan: Journal of Volcanology and Geothermal Research, v. 89, p. 275–301.
1. Wiebe, R., Holden, J., Coombs, M., Wobus, R., Schuh, K., and Plummer, B., 1997, The Cadillac Mountain intrusive complex, Maine: The role of shallow-level magma chamber processes in the generation of A-type granites, in Sinha, A., Whalen, J., and Hogan, J., eds., The Nature of Magmatism in the Appalachian Orogen: Geological Society of America Memoir 191, p. 397–418.
Science and Products
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...
Williams, Dee M.; Avery, Vic F.; Coombs, Michelle L.; Cox, Dale A.; Horwitz, Lief R.; McBride, Sara K.; McClymont, Ryan J.; Moran, Seth C.
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...
Loewen, Matthew W.; Pavel Izbekof; Justin Moshrefzadeh; Coombs, Michelle L.; Jessica Larsen; Graham, Nathan; Michelle Harbin; Waythomas, Christopher F.; Wallace, Kristi 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...
Coombs, Michelle L.; Wallace, Kristi; Cameron, Cheryl; Lyons, John J.; Wech, Aaron; Angeli, Kim M.; Cervelli, Peter 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...
Neal, Christina A.; Brantley, Steven; Antolik, Loren; Babb, Janet; Burgess, Matthew K.; Cappos, Michael; Chang, Jefferson; Conway, Sarah; Desmither, Liliana; Dotray, Peter; Elias, Tamar; Fukunaga, Pauline; Fuke, Steven; Johanson, Ingrid; Kamibayashi, Kevan; Kauahikaua, James P.; Lee, R. Lopaka; Pekalib, S.; Miklius, Asta; Shiro, Brian; Swanson, Don; Nadeau, Patricia; Zoeller, Michael H.; Okubo, P.; Parcheta, Carolyn; Patrick, Matthew R.; Tollett, William; Trusdell, Frank A.; Younger, Edward (Frank); Montgomery-brown, Emily; Anderson, Kyle R.; Poland, Michael P.; Ball, Jessica L.; Bard, Joseph A.; Coombs, Michelle L.; Dietterich, Hannah R.; Kern, Christoph; Thelen, Weston; Cervelli, Peter; Orr, Tim R.; Houghton, Bruce F.; Gansecki, Cheryl; Hazlett, Richard; Lundgren, Paul; Diefenbach, Angela K.; Lerner, Allan; Waite, Greg; Kelly, Peter J.; Clor, Laura E.; Werner, Cynthia; Burgess, Matthew; Mulliken, Katherine; Fisher, Gary 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...
Coombs, Michelle L.; Wech, Aaron; Haney, Matthew M.; Lyons, John J.; Schneider, David; Schwaiger, Hans; Wallace, Kristi; Fee, David; Freymueller, Jeffrey T.; Schaefer, Janet; Tepp, Gabrielle
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...
Coombs, Michelle L.; Larsen, Jessica F.; Neal, Christina A. 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...
De Angelis, S. H.; Larsen, J.; Coombs, Michelle L.; Dunn, A.; Hayden, Leslie A.
Significance of a near-source tephra-stratigraphic sequence to the eruptive history of Hayes Volcano, south-central Alaska
Bluffs along the Hayes River valley, 31 km northeast and 40 km downstream from Hayes Volcano, reveal volcanic deposits that shed new light on its eruptive history. Three thick (>10 cm) and five thin (<10 cm) tephra-fall deposits are dacitic in whole rock composition and contain high proportions of amphibole to pyroxene and minor biotite and...
Wallace, Kristi; Coombs, Michelle L.; Hayden, Leslie A.; Waythomas, Christopher F. Cogenetic late Pleistocene rhyolite and cumulate diorites from Augustine Volcano revealed by SIMS 238U-230Th dating of zircon, and implications for silicic magma generation by extraction from mush
Augustine Volcano, a frequently active andesitic island stratocone, erupted a late Pleistocene rhyolite pumice fall that is temporally linked through zircon geochronology to cumulate dioritic blocks brought to the surface in Augustine's 2006 eruption. Zircon from the rhyolite yield a 238U-230Th age of ∼25 ka for their unpolished rims, and...
Coombs, Michelle L.; Vazquez, Jorge A. Constructing a reference tephrochronology for Augustine Volcano, Alaska
Augustine Volcano is the most historically active volcano in Alaska's populous Cook Inlet region. Past on-island work on pre-historic tephra deposits mainly focused on using tephra layers as markers to help distinguish among prevalent debris-avalanche deposits on the island (Waitt and Beget, 2009, USGS Prof Paper 1762), or as source material for...
Wallace, Kristi; Coombs, Michelle L. 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...
Wessels, Rick L.; Vaughan, R. Greg; Patrick, Matthew R.; Coombs, Michelle L. 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...
Bleick, Heather A.; Coombs, Michelle L.; Cervelli, Peter F.; Bull, Katharine F.; Wessels, Rick
Volcano Watch — Bogoslof Volcano, Alaska: ongoing eruption through the Bering Sea
Hawai‘i is not the only island in the United States with an ongoing eruption involving hot lava and cold water.
Monitoring Alaska’s Remote and Restless Bogoslof Volcano
Bogoslof volcano, located in the Aleutian Islands about 98 km (61 mi) northwest of Dutch Harbor/Unalaska, is in an active eruption sequence that began in mid-December 2016 and continues today.