Peter Kelly
I am a research geologist based at the Cascades Volcano Observatory. I work to better understand magmatic and hydrothermal systems through research and monitoring of volcanic gas emissions.
I work on US volcanoes as a member of the USGS Volcano Emissions Project and internationally as a member of the USAID-USGS Volcano Disaster Assistance Program (VDAP). This work includes an emphasis on developing and applying new technologies to implement real-time gas monitoring on volcanoes. Prior to joining the USGS in 2008, I spent two years at the University of New Hampshire working on a NOAA-funded project to monitor air pollution.
Education and Certifications
M.S., Geochemistry, New Mexico Institute of Mining and Technology, Socorro, NM, 2006
B.S., Geology, Northeastern University, Boston, MA, 2003
Science and Products
The 2017-19 activity at Mount Agung in Bali (Indonesia): Intense unrest, monitoring, crisis response, evacuation, and eruption
The 2018 rift eruption and summit collapse of Kilauea Volcano
Insights into the mechanisms of phreatic eruptions from continuous high frequency volcanic gas monitoring: Rincón de la Vieja volcano, Costa Rica
Evolution of the 2015 Cotopaxi eruption revealed by combined geochemical & seismic observations
Multi-year high-frequency hydrothermal monitoring of selected high-threat Cascade Range volcanoes
Construction of probabilistic event trees for eruption forecasting at Sinabung volcano, Indonesia 2013–14
Monitoring gas and heat emissions at Norris Geyser Basin, Yellowstone National Park, USA based on a combined eddy covariance and Multi-GAS approach
Evidence for degassing of fresh magma during the 2004-2008 eruption of Mount St. Helens: Subtle signals from the hydrothermal system
Magmatic degassing, lava dome extrusion, and explosions from Mount Cleveland volcano, Alaska, 2011–2015: Insight into the continuous nature of volcanic activity over multi-year timescales
Long period seismicity and very long period infrasound driven by shallow magmatic degassing at Mount Pagan, Mariana Islands
Long period (LP) seismicity and very long period infrasound (iVLP) were recorded during continuous degassing from Mount Pagan, Mariana Islands, in July 2013 to January 2014. The frequency content of the LP and iVLP events and delay times between the two arrivals were remarkably stable and indicate nearly co-located sources. Using phase-weighted stacking over similar events to dampen noise, we find
Decadal-scale variability of diffuse CO2 emissions and seismicity revealed from long-term monitoring (1995–2013) at Mammoth Mountain, California, USA
Rapid chemical evolution of tropospheric volcanic emissions from Redoubt Volcano, Alaska, based on observations of ozone and halogen-containing gases
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Filter Total Items: 27
The 2017-19 activity at Mount Agung in Bali (Indonesia): Intense unrest, monitoring, crisis response, evacuation, and eruption
After 53 years of quiescence, Mount Agung awoke in August 2017, with intense seismicity, measurable ground deformation, and thermal anomalies in the summit crater. Although the seismic unrest peaked in late September and early October, the volcano did not start erupting until 21 November. The most intense explosive eruptions with accompanying rapid lava effusion occurred between 25 and 29 NovemberAuthorsD.K. Syahbana, K. Kasbani, G. Suantika, O. Prambada, A. Andreas, U. Saing, S. Kunrat, S.L. Andreastuti, S. Martanto, E. Kriswati, Y. Suparman, H. Humaida, Sarah E. Ogburn, Peter J. Kelly, John Wellik, Heather Wright, Jeremy D. Pesicek, Rick Wessels, Christoph Kern, Michael Lisowski, Angela K. Diefenbach, Michael P. Poland, Francois Beauducel, R. Greg Vaughan, John S. Pallister, Jacob B. LowensternThe 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 G. 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 DambyInsights into the mechanisms of phreatic eruptions from continuous high frequency volcanic gas monitoring: Rincón de la Vieja volcano, Costa Rica
Understanding the trigger mechanisms of phreatic eruptions is key to mitigating the effects of these hazardous but poorly forecastable volcanic events. It has recently been established that high-rate volcanic gas observations are potentially very suitable to identifying the source processes driving phreatic eruptions, and to eventually detecting precursory changes prior to individual phreatic blasAuthorsAngelo Battaglia, J. Maarten de Moor, Alessandro Aiuppa, Geoffroy Avard, Henriette Bakkar, Marcello Bitetto, M. M. Mora Fernández, Peter J. Kelly, Gaetano Giudice, Dario Delle Donne, Hairo VillalobosEvolution of the 2015 Cotopaxi eruption revealed by combined geochemical & seismic observations
Through integration of multiple data streams to monitor volcanic unrest scientists are able to make more robust eruption forecast and to obtain a more holistic interpretation of volcanic systems. We examined gas emission and gas geochemistry, seismic and petrologic data recorded during the 2015 unrest of Cotopaxi (Ecuador) in order to decipher the origin and temporal evolution of this eruption. IdAuthorsSilvana Hidalgo, Jean Battaglia, Santiago Arellano, Daniel Sierra, Benjamin Bernard, Rene Parra, Peter J. Kelly, Florian Dinger, Charlotte Barrington, Pablo SamaniegoMulti-year high-frequency hydrothermal monitoring of selected high-threat Cascade Range volcanoes
From 2009 to 2015 the U.S. Geological Survey (USGS) systematically monitored hydrothermal behavior at selected Cascade Range volcanoes in order to define baseline hydrothermal and geochemical conditions. Gas and water data were collected regularly at 25 sites on 10 of the highest-risk volcanoes in the Cascade Range. These sites include near-summit fumarole groups and springs/streams that show cleaAuthorsI.M. Crankshaw, Stacey A. Archfield, A. C. Newman, Deborah Bergfeld, Laura E. Clor, Peter J. Kelly, William C. Evans, Kurt R. Spicer, Steven E. IngebritsenConstruction of probabilistic event trees for eruption forecasting at Sinabung volcano, Indonesia 2013–14
Eruptions of Sinabung volcano, Indonesia have been ongoing since 2013. Since that time, the character of eruptions has changed, from phreatic to phreatomagmatic to magmatic explosive eruptions, and from production of a lava dome that collapsed to a subsequent thick lava flow that slowly ceased to be active, and later, to a new lava dome. As the eruption progressed, event trees were constructed toAuthorsHeather M. Wright, John S. Pallister, Wendy A. McCausland, Julia P. Griswold, Supriyati Andreastuti, Agus Budianto, Sofyan Primulyana, Maurizio Battaglia, Angie Diefenbach, John W. Ewert, Peter J. Kelly, Christoph Kern, Martin R. LaFevers, Andrew B. Lockhart, Jeffrey N. Marso, Gari C. Mayberry, Steve P. Schilling, Rick Wessels, Randall A. White, Nurnaning Aisyah, Nugraha Kartadinata, Kristianto, Raditya Putra, Ugan Boyson Saing, Agus Solihin, Yasa Suparman, Devy Damil Syahbana, Hetty TriastutyMonitoring gas and heat emissions at Norris Geyser Basin, Yellowstone National Park, USA based on a combined eddy covariance and Multi-GAS approach
We quantified gas and heat emissions in an acid-sulfate, vapor-dominated area (0.04-km2) of Norris Geyser Basin, located just north of the 0.63 Ma Yellowstone Caldera and near an area of anomalous uplift. From 14 May to 3 October 2016, an eddy covariance system measured half-hourly CO2, H2O and sensible (H) and latent (LE) heat fluxes and a Multi-GAS instrument measured (1 Hz frequency) atmospheriAuthorsJennifer L. Lewicki, Peter J. Kelly, Deborah Bergfeld, R. Greg Vaughan, Jacob B. LowensternEvidence for degassing of fresh magma during the 2004-2008 eruption of Mount St. Helens: Subtle signals from the hydrothermal system
Results from chemical and isotopic analyses of water and gas collected between 2002 and 2016 from sites on and around Mount St. Helens are used to assess magmatic degassing related to the 2004-2008 eruption. During 2005 the chemistry of hot springs in The Breach of Mount St. Helens showed no obvious response to the eruption, and over the next few years, changes were subtle, giving only slight indiAuthorsDeborah Bergfeld, William C. Evans, Kurt R. Spicer, Andrew G. Hunt, Peter J. KellyMagmatic degassing, lava dome extrusion, and explosions from Mount Cleveland volcano, Alaska, 2011–2015: Insight into the continuous nature of volcanic activity over multi-year timescales
Mount Cleveland volcano (1730 m) is one of the most active volcanoes in the Aleutian arc, Alaska, but heightened activity is rarely accompanied by geophysical signals, which makes interpretation of the activity difficult. In this study, we combine volcanic gas emissions measured for the first time in August 2015 with longer-term measurements of thermal output and lava extrusion rates between 2011AuthorsCynthia Werner, Christoph Kern, Diego Coppola, John J. Lyons, Peter J. Kelly, Kristi L. Wallace, David J. Schneider, Rick WesselsLong period seismicity and very long period infrasound driven by shallow magmatic degassing at Mount Pagan, Mariana Islands
Long period (LP) seismicity and very long period infrasound (iVLP) were recorded during continuous degassing from Mount Pagan, Mariana Islands, in July 2013 to January 2014. The frequency content of the LP and iVLP events and delay times between the two arrivals were remarkably stable and indicate nearly co-located sources. Using phase-weighted stacking over similar events to dampen noise, we find
AuthorsJohn J. Lyons, Matthew M. Haney, Cynthia A. Werner, Peter J. Kelly, Matthew R. Patrick, Christoph Kern, Frank A. TrusdellDecadal-scale variability of diffuse CO2 emissions and seismicity revealed from long-term monitoring (1995–2013) at Mammoth Mountain, California, USA
Mammoth Mountain, California, is a dacitic volcano that has experienced several periods of unrest since 1989. The onset of diffuse soil CO2 emissions at numerous locations on the flanks of the volcano began in 1989–1990 following an 11-month period of heightened seismicity. CO2 emission rates were measured yearly from 1995 to 2013 at Horseshoe Lake (HSL), the largest tree kill area on Mammoth MounAuthorsCynthia A. Werner, Deborah Bergfeld, Chris Farrar, Michael P. Doukas, Peter J. Kelly, Christoph KernRapid chemical evolution of tropospheric volcanic emissions from Redoubt Volcano, Alaska, based on observations of ozone and halogen-containing gases
We report results from an observational and modeling study of reactive chemistry in the tropospheric plume emitted by Redoubt Volcano, Alaska. Our measurements include the first observations of Br and I degassing from an Alaskan volcano, the first study of O3 evolution in a volcanic plume, as well as the first detection of BrO in the plume of a passively degassing Alaskan volcano. This study alsoAuthorsCynthia A. Werner, Peter J. Kelly, Christoph Kern, T.J. Roberts, A. Aluppe - News