My interests are in the physics of volcanoes; the processes that cause the changes that we measure and phenomena we see. This includes the mechanisms of magma transport, volcanic structure and magma storage, and during eruptions the transport of ash in the atmosphere. I use numerical methods, including artificial intelligence, to model data, and Bayesian methods to constrain the models with data.
I have been a Geophysicist with the Cascades Volcano Observatory since 1996. My major accomplishments are as follows:
- Constructed a model for shallow water flow, modeled floods throughout western US
- Showed that a 2d shallow water model effectively modeled two millennial floods on the Verde River, Arizona, effectively verifying the three-dimensional variation of stage to give unique discharge of nearly 3200 cubic meters per second. This discharge was verified by flow through a dam immediately downstream.
- Constructed a dambreak model for the Pakistan Army to mitigate the Haittian landslide dam that had just buried 2 entire villages. Modeling determined how much to downcut the landslide to preserve infrastructure downstream. The cut was made and the resulting flow matched the prediction of my model. For this work Dan O'Connell and I received recognition from the Pakistan Army.
- Constructed a shallow flow model for debris flows and avalanches to model USGS flume data.
- Co-construction of Ash3d, an ash transport program, along with Hans Schwaiger (USGS) and Larry Mastin (USGS). Used Bayesian methods to refine forecasts of ash clouds.
- Used gravity and seismic data to quantify gravitational component, verify existing volcano-tectonic features, and illustrate the deep structure cradling magma and mush in the volcano.
Past Appointments
- NRC postdoctoral Fellow 1979
- Submersible work with US Navy, 1986-1989
- Geophysicist, adjunct, Oceanography Dept, University of Washington, 1986-1999
- Visiting Scientist, Meteorological Office, Exeter, England, 2016
Professional Experience
Groundwater Flow and Subsidence, 1980-1982
Volcano Deformation and Geophysics, 1981-1986
Established magnetization and cooling rate of Mount Saint Helens growing dome.Seafloor Volcanism, Deformation, and Thermal History, 1986-1992
Member of team that discovered SeaCliff hydrothermal field within Escanabah Trough.
Corrected the thermal structure of oceanic lithosphere to account for phase changes during cooling.Deformation Chief, Hawaiian Volcano Observatory, 1992 - 1996
Established GPS/GNSS network on south flank of Kilauea volcano.
Measured large, episodic monthly changes in rate of south flank movement on Kilauea volcano.
Established that the south flank of Kilauea volcano had a landslide structure.WORKSHOPS and REVIEW PANELS
Workshop that formed the RIDGE consortium of academia and government to study the ocean floor, 1988
Institute of Volcanic Studies, University of Washington, Seattle, WA, 1990-1992
Rosenstiel School of Marine and Atmospheric Science Workshop, SAR Interferometry and Surface Change Detection, 1994
USGS NEHRP Review panel for Pacific Northwest, 1994, 1995, 2002
USGS Multidisciplinary Workshop to assess “A unified approach toward probabilistic risk assessment for earthquakes, floods, landslides, and volcanoes” within the USGS, Golden, CO, November 16-17, 1999. Funded by the USGS Urban Hazards Initiative.
USGS Working Group to assess research directions to improve methods to solve advection-diffusion equations, Denver, CO, August 1999
Member International Committee to organize and plan mathematical workshops on granular flow.
GEOPRISMS working group funded for active and passive Mount St. Helens seismic experiments.
CHAIR POSITIONS
RIDGE Panel to plan and assemble a proposal to Congress to establish RIDGE Program, 1988
USGS Research Evaluation Panel, Volcano Hazards Team, 1995
1st Federal Interagency Hydrologic Modeling Conference Panel, “Formulation and use of flood models within and outside the Federal government”, Las Vegas, NV, April 1998
EXPERT CONSULTANT
Seismo-tectonic program, US Bureau of Reclamation, Denver, CO, 1996-2012
Ferguson rockslide, Merced River Canyon, US Forest Service, 2005-2012
Avalanche and debris flow program, Ecole Polytechnique Federale de Lausanne, Switzerland, 2005-2012
Hattian landslide dambreak, General Tahir Hayat, Pakistan Army, Pakistan, 2005-2009
Education and Certifications
PhD, Geophysics, Stanford University 1979
MS, Geophysics, Stanford University, 1977
BS, Geology, CSU Hayward, 1974
BA, Physics, CSU Hayward, 1973
Affiliations and Memberships*
Member, American Geophysical Union
Member, Geological Society of America
Past memberships in Society of Industrial and Applied Mathematics, Seismological Society of America
Honors and Awards
Special Service Award, US Geological Survey, for work on granular flows
Abstracts and Presentations
1992 keynote speaker Penrose Conference on “Water-Volcano Interaction”, Warm Springs, OR
1999 keynote speaker UNAVCO Volcano Geodesy Workshop, International NAVSTAR Consortium, Jackson Hole, WY
2003 keynote speaker Isaac Newton Institute for Mathematical Sciences Workshop, Bristol, England
2012 keynote speaker IUGG, International Congress for Theoretical and Applied Mechanics, Beijing, China
2018 keynote speaker Denver Geophysical Society, Denver, Colorado
Science and Products
Density structure of the island of Hawai’i and the implications for gravity-driven motion of the south flank of Kilauea volcano
Diverse cataclysmic floods from Pleistocene glacial Lake Missoula
Evolution of faulting induced by deep fluid injection, Paradox Valley, Colorado
The Missoula and Bonneville floods—A review of ice-age megafloods in the Columbia River basin
Ongoing efforts to make ash-cloud model forecasts more accurate
Volcano dome dynamics at Mount St. Helens: Deformation and intermittent subsidence monitored by seismicity and camera imagery pixel offsets
Using monitoring and modeling to define the hazard posed by the reactivated Ferguson rock slide, Merced Canyon, California
Volcanic tremor masks its seismogenic source: Results from a study of noneruptive tremor recorded at Mount St. Helens, Washington
Instability of Hawaiian volcanoes
User’s guide and reference to Ash3d—A three-dimensional model for Eulerian atmospheric tephra transport and deposition
Injection, transport, and deposition of tephra during event 5 at Redoubt Volcano, 23 March, 2009
Faulting within the Mount St. Helens conduit and implications for volcanic earthquakes
Science and Products
- Publications
Filter Total Items: 34
Density structure of the island of Hawai’i and the implications for gravity-driven motion of the south flank of Kilauea volcano
The discovery that large landslides dissected the Hawaiian islands, scattering debris over thousands of square kilometers of seafloor, changed our ideas of island growth and evolution. The evidence is consistent with catastrophic flank collapse during volcano growth, and draws our focus to the currently active island of Hawai’i, the volcanoes Mauna Loa and Kīlauea, and particularly to the activelyAuthorsRoger P. Denlinger, Ashton F. FlindersDiverse cataclysmic floods from Pleistocene glacial Lake Missoula
In late Wisconsin time, the Purcell Trench lobe of the Cordilleran ice sheet dammed the Clark Fork of the Columbia River in western Montana, creating glacial Lake Missoula. During part of this epoch, the Okanogan lobe also dammed the Columbia River downstream, creating glacial Lake Columbia in northeast Washington. Repeated failure of the Purcell Trench ice dam released glacial Lake Missoula, causAuthorsRoger P. Denlinger, David L. George, Charles M. Cannon, Jim E. O'Connor, Richard B. WaittEvolution of faulting induced by deep fluid injection, Paradox Valley, Colorado
High‐pressure fluid injection into a subhorizontal confined aquifer at 4.3–4.6 km depth induced >7000>7000 earthquakes between 1991 and 2012 within once seismically quiescent Paradox Valley in Colorado, with magnitudes up to MwMw 3.9. Earthquake hypocenters expanded laterally away from the well with time, defining the margins of the aquifer pressurized by injection at the well. Within 5 km of theAuthorsRoger P. Denlinger, Daniel R. H. O'ConnellThe Missoula and Bonneville floods—A review of ice-age megafloods in the Columbia River basin
The Channeled Scabland of eastern Washington State, USA, brought megafloods to the scientific forefront. A 30,000-km2 landscape of coulees and cataracts carved into the region’s loess-covered basalt attests to overwhelming volumes of energetic water. The scarred landscape, garnished by huge boulder bars and far-travelled ice-rafted erratics, spurred J Harlen Bretz’s vigorously disputed flood hypotAuthorsJim E. O'Connor, Victor R. Baker, Richard B. Waitt, Larry N Smith, Charles M. Cannon, David L. George, Roger P. DenlingerOngoing efforts to make ash-cloud model forecasts more accurate
The 2010 eruption of Eyjafjallajökull volcano in Iceland changed the rules for air travel in Europe and introduced the use of restricted fly zones based on ash-cloud concentrations calculated by dispersion models. This change prompted a sustained effort to improve the accuracy of ash-cloud model forecasts. In this paper we describe how this goal is being advanced on three fronts: (1) assessing curAuthorsLarry G. Mastin, Alexa R. Van Eaton, David Schneider, Roger P. DenlingerVolcano dome dynamics at Mount St. Helens: Deformation and intermittent subsidence monitored by seismicity and camera imagery pixel offsets
The surface deformation field measured at volcanic domes provides insights into the effects of magmatic processes, gravity- and gas-driven processes, and the development and distribution of internal dome structures. Here we study short-term dome deformation associated with earthquakes at Mount St. Helens, recorded by a permanent optical camera and seismic monitoring network. We use Digital Image CAuthorsJacqueline T. Salzer, Weston A. Thelen, Mike R. James, Thomas R. Walter, Seth C. Moran, Roger P. DenlingerUsing monitoring and modeling to define the hazard posed by the reactivated Ferguson rock slide, Merced Canyon, California
Rapid onset natural disasters such as large landslides create a need for scientific information about the event, which is vital to ensuring public safety, restoring infrastructure, preventing additional damage, and resuming normal economic activity. At the same time, there is limited data available upon which to base reliable scientific responses. Monitoring movement and modeling runout are mechanAuthorsJerome V. De Graff, Alan J. Gallegos, Mark E. Reid, Richard G. Lahusen, Roger P. DenlingerVolcanic tremor masks its seismogenic source: Results from a study of noneruptive tremor recorded at Mount St. Helens, Washington
On 2 October 2004, a significant noneruptive tremor episode occurred during the buildup to the 2004–2008 eruption of Mount St. Helens (Washington). This episode was remarkable both because no explosion followed, and because seismicity abruptly stopped following the episode. This sequence motivated us to consider a model for volcanic tremor that does not involve energetic gas release from magma butAuthorsRoger P. Denlinger, Seth C. MoranInstability of Hawaiian volcanoes
Hawaiian volcanoes build long rift zones and some of the largest volcanic edifices on Earth. For the active volcanoes on the Island of Hawai‘i, the growth of these rift zones is upward and seaward and occurs through a repetitive process of decades-long buildup of a magma-system head along the rift zones, followed by rapid large-scale displacement of the seaward flank in seconds to minutes. This laAuthorsRoger P. Denlinger, Julia K. MorganUser’s guide and reference to Ash3d—A three-dimensional model for Eulerian atmospheric tephra transport and deposition
Ash3d is a three-dimensional Eulerian atmospheric model for tephra transport, dispersal, and deposition to study and forecast hazards of volcanic ash clouds and tephra fall. In this report, we explain how to set up simulations using a web interface, and how to view and interpret model output. We also summarize the architecture of the model and some of its properties.AuthorsLarry G. Mastin, Michael J. Randall, Hans F. Schwaiger, Roger P. DenlingerInjection, transport, and deposition of tephra during event 5 at Redoubt Volcano, 23 March, 2009
Among the events of the 2009 eruption at Redoubt Volcano, Alaska, event 5 was the best documented by radar, satellite imagery, and deposit mapping. We use the new Eulerian tephra transport model Ash3d to simulate transport and deposition of event 5 tephra at distances up to 350 km. The eruption, which started at about 1230 UTC on 23 March, 2009, sent a plume from the vent elevation (estimated at 2AuthorsLarry G. Mastin, Hans F. Schwaiger, David Schneider, Kristi L. Wallace, Janet Schaefer, Roger P. DenlingerFaulting within the Mount St. Helens conduit and implications for volcanic earthquakes
The 2004–2008 eruption of Mount St. Helens produced seven dacite spines mantled by cataclastic fault rocks, comprising an outer fault core and an inner damage zone. These fault rocks provide remarkable insights into the mechanical processes that accompany extrusion of degassed magma, insights that are useful in forecasting dome-forming eruptions. The outermost part of the fault core consists of fiAuthorsJohn S. Pallister, Katharine V. Cashman, Jonathan T. Hagstrum, Nicholas M. Beeler, Seth C. Moran, Roger P. Denlinger
*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