James W. Vallance
I supervise the field geology and hydrology group at Cascades Volcano Observatory. My research focuses on postglacial volcanism and hazards at volcanoes such as Mount Rainier and Mount St. Helens in Washington State. I also study the nature and behavior of lahars, floods, avalanches, pyroclastic flows, and dome growth.
Education and Certifications
PhD Geology, Michigan Technological University, 1994
MS Geology, Colorado University, Boulder, 1986
BA Geology, Colorado University, Boulder, 1980
Affiliations and Memberships*
American Geophysical Union
Geological Society of America
Honors and Awards
Fellow, Geological Society of America
NSERC and NSF postdoctoral fellowships, McGill University, Canada
Science and Products
Filter Total Items: 32
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, 2006 (events
Authors
Michelle L. Coombs, Katharine F. Bull, James W. Vallance, David J. Schneider, Evan E. Thoms, Rick L. Wessels, Robert G. McGimsey
Pyroclastic flows, lahars, and mixed avalanches generated during the 2006 eruption of Augustine Volcano: Chapter 10 in The 2006 eruption of Augustine Volcano, Alaska
Each of the three phases of the 2006 eruption at Augustine Volcano had a distinctive eruptive style and flowage deposits. From January 11 to 28, the explosive phase comprised short vulcanian eruptions that punctuated dome growth and produced volcanowide pyroclastic flows and more energetic hot currents whose mobility was influenced by efficient mixing with and vaporization of snow. Initially, hot
Authors
James W. Vallance, Katharine F. Bull, Michelle L. Coombs
Photographic documentation of the evolution of Crater Glacier, Mount St. Helens, Washington, September 2006–November 2009
Lava-dome emplacement through a glacier was observed for the first time during the 2004-08 eruption of Mount St. Helens and documented using photography, photogrammetry, and geodetic measurements. Previously published reports present such documentation through September 2006; this report extends that documentation until November 2009.
Authors
Joseph S. Walder, Steven P. Schilling, David R. Sherrod, James W. Vallance
Mount St. Helens: A 30-year legacy of volcanism
The spectacular eruption of Mount St. Helens on 18 May 1980 electrified scientists and the public. Photodocumentation of the colossal landslide, directed blast, and ensuing eruption column—which reached as high as 25 kilometers in altitude and lasted for nearly 9 hours—made news worldwide. Reconnaissance of the devastation spurred efforts to understand the power and awe of those moments (Figure 1)
Authors
James W. Vallance, Cynthia A. Gardner, William E. Scott, Richard M. Iverson, Thomas C. Pierson
Eruption-related lahars and sedimentation response downstream of Mount Hood: Field guide to volcaniclastic deposits along the Sandy River, Oregon
Late Holocene dome-building eruptions at Mount Hood during the Timberline and Old Maid eruptive periods resulted in numerous dome-collapse pyroclastic flows and lahars that moved large volumes of volcaniclastic sediment into temporary storage in headwater canyons of the Sandy River. During each eruptive period, accelerated sediment loading to the river through erosion and remobilization of volcani
Authors
Thomas C. Pierson, Scott W. Akins, James W. Vallance, Patrick T. Pringle
Eruption-related lahars and sedimentation response downstream of Mount Hood: Field guide to volcaniclastic deposits along the Sandy River, Oregon
Late Holocene dome-building eruptions at Mount Hood during the Timberline and Old Maid eruptive periods resulted in numerous dome-collapse pyroclastic flows and lahars that moved large volumes of volcaniclastic sediment into temporary storage in headwater canyons of the Sandy River. During each eruptive period, accelerated sediment loading to the river through erosion and remobilization of volcani
Authors
Tom C. Pierson, William E. Scott, James W. Vallance, Patrick T. Pringle
Volcan Baru: Eruptive History and Volcano-Hazards Assessment
Volcan Baru is a potentially active volcano in western Panama, about 35 km east of the Costa Rican border. The volcano has had four eruptive episodes during the past 1,600 years, including its most recent eruption about 400?500 years ago. Several other eruptions occurred in the prior 10,000 years. Several seismic swarms in the 20th century and a recent swarm in 2006 serve as reminders of a restles
Authors
David R. Sherrod, James W. Vallance, Arkin Tapia Espinosa, John P. McGeehin
Effects of lava-dome growth on the crater glacier of Mount St. Helens, Washington
The process of lava-dome emplacement through a glacier
was observed for the first time as the 2004-6 eruption of
Mount St. Helens proceeded. The glacier that had grown in the
crater since the cataclysmic 1980 eruption was split in two by
the new lava dome. The two parts of the glacier were successively squeezed against the crater wall. Photography, photogrammetry, and geodetic measurements doc
Authors
Joseph S. Walder, Steve P. Schilling, James W. Vallance, Richard G. LaHusen
Photogeologic maps of the 2004-2005 Mount St. Helens eruption
The 2004-5 eruption of Mount St. Helens, still ongoing
as of this writing (September 2006), has comprised chiefly
lava dome extrusion that produced a series of solid, faultgouge-mantled dacite spines. Vertical aerial photographs
taken every 2 to 4 weeks, visual observations, and oblique
photographs taken from aircraft and nearby observation
points provide the basis for two types of photogeolo
Authors
Trystan M. Herriott, David R. Sherrod, John S. Pallister, James W. Vallance
Seismic and acoustic recordings of an unusually large rockfall at Mount St. Helens, Washington
On 29 May 2006 a large rockfall off the Mount St. Helens lava dome produced an atmospheric plume that was reported by airplane pilots to have risen to 6,000 m above sea level and interpreted to be a result of an explosive event. However, subsequent field reconnaissance found no evidence of a ballistic field, indicating that there was no explosive component. The rockfall produced complex seismic an
Authors
Seth C. Moran, R.S. Matoza, M.A. Garces, M.A.H. Hedlin, D. Bowers, William E. Scott, David R. Sherrod, James W. Vallance
Emplacement of a silicic lava dome through a crater glacier: Mount St Helens, 2004-06
The process of lava-dome emplacement through a glacier was observed for the first time after Mount St Helens reawakened in September 2004. The glacier that had grown in the crater since the cataclysmic 1980 eruption was split in two by the new lava dome. The two parts of the glacier were successively squeezed against the crater wall. Photography, photogrammetry and geodetic measurements document g
Authors
Joseph S. Walder, Richard G. Lahusen, James W. Vallance, Steve P. Schilling
Tephra deposits for the past 2600 years from Irazú Volcano, Costa Rica: Chapter 12 in Volcanic hazards in Central America
No abstract available.
Authors
S.K. Clark, M. K. Reagan, D.A. Trimble
Science and Products
- Publications
Filter Total Items: 32
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, 2006 (eventsAuthorsMichelle L. Coombs, Katharine F. Bull, James W. Vallance, David J. Schneider, Evan E. Thoms, Rick L. Wessels, Robert G. McGimseyPyroclastic flows, lahars, and mixed avalanches generated during the 2006 eruption of Augustine Volcano: Chapter 10 in The 2006 eruption of Augustine Volcano, Alaska
Each of the three phases of the 2006 eruption at Augustine Volcano had a distinctive eruptive style and flowage deposits. From January 11 to 28, the explosive phase comprised short vulcanian eruptions that punctuated dome growth and produced volcanowide pyroclastic flows and more energetic hot currents whose mobility was influenced by efficient mixing with and vaporization of snow. Initially, hotAuthorsJames W. Vallance, Katharine F. Bull, Michelle L. CoombsPhotographic documentation of the evolution of Crater Glacier, Mount St. Helens, Washington, September 2006–November 2009
Lava-dome emplacement through a glacier was observed for the first time during the 2004-08 eruption of Mount St. Helens and documented using photography, photogrammetry, and geodetic measurements. Previously published reports present such documentation through September 2006; this report extends that documentation until November 2009.AuthorsJoseph S. Walder, Steven P. Schilling, David R. Sherrod, James W. VallanceMount St. Helens: A 30-year legacy of volcanism
The spectacular eruption of Mount St. Helens on 18 May 1980 electrified scientists and the public. Photodocumentation of the colossal landslide, directed blast, and ensuing eruption column—which reached as high as 25 kilometers in altitude and lasted for nearly 9 hours—made news worldwide. Reconnaissance of the devastation spurred efforts to understand the power and awe of those moments (Figure 1)AuthorsJames W. Vallance, Cynthia A. Gardner, William E. Scott, Richard M. Iverson, Thomas C. PiersonEruption-related lahars and sedimentation response downstream of Mount Hood: Field guide to volcaniclastic deposits along the Sandy River, Oregon
Late Holocene dome-building eruptions at Mount Hood during the Timberline and Old Maid eruptive periods resulted in numerous dome-collapse pyroclastic flows and lahars that moved large volumes of volcaniclastic sediment into temporary storage in headwater canyons of the Sandy River. During each eruptive period, accelerated sediment loading to the river through erosion and remobilization of volcaniAuthorsThomas C. Pierson, Scott W. Akins, James W. Vallance, Patrick T. PringleEruption-related lahars and sedimentation response downstream of Mount Hood: Field guide to volcaniclastic deposits along the Sandy River, Oregon
Late Holocene dome-building eruptions at Mount Hood during the Timberline and Old Maid eruptive periods resulted in numerous dome-collapse pyroclastic flows and lahars that moved large volumes of volcaniclastic sediment into temporary storage in headwater canyons of the Sandy River. During each eruptive period, accelerated sediment loading to the river through erosion and remobilization of volcaniAuthorsTom C. Pierson, William E. Scott, James W. Vallance, Patrick T. PringleVolcan Baru: Eruptive History and Volcano-Hazards Assessment
Volcan Baru is a potentially active volcano in western Panama, about 35 km east of the Costa Rican border. The volcano has had four eruptive episodes during the past 1,600 years, including its most recent eruption about 400?500 years ago. Several other eruptions occurred in the prior 10,000 years. Several seismic swarms in the 20th century and a recent swarm in 2006 serve as reminders of a restlesAuthorsDavid R. Sherrod, James W. Vallance, Arkin Tapia Espinosa, John P. McGeehinEffects of lava-dome growth on the crater glacier of Mount St. Helens, Washington
The process of lava-dome emplacement through a glacier was observed for the first time as the 2004-6 eruption of Mount St. Helens proceeded. The glacier that had grown in the crater since the cataclysmic 1980 eruption was split in two by the new lava dome. The two parts of the glacier were successively squeezed against the crater wall. Photography, photogrammetry, and geodetic measurements docAuthorsJoseph S. Walder, Steve P. Schilling, James W. Vallance, Richard G. LaHusenPhotogeologic maps of the 2004-2005 Mount St. Helens eruption
The 2004-5 eruption of Mount St. Helens, still ongoing as of this writing (September 2006), has comprised chiefly lava dome extrusion that produced a series of solid, faultgouge-mantled dacite spines. Vertical aerial photographs taken every 2 to 4 weeks, visual observations, and oblique photographs taken from aircraft and nearby observation points provide the basis for two types of photogeoloAuthorsTrystan M. Herriott, David R. Sherrod, John S. Pallister, James W. VallanceSeismic and acoustic recordings of an unusually large rockfall at Mount St. Helens, Washington
On 29 May 2006 a large rockfall off the Mount St. Helens lava dome produced an atmospheric plume that was reported by airplane pilots to have risen to 6,000 m above sea level and interpreted to be a result of an explosive event. However, subsequent field reconnaissance found no evidence of a ballistic field, indicating that there was no explosive component. The rockfall produced complex seismic anAuthorsSeth C. Moran, R.S. Matoza, M.A. Garces, M.A.H. Hedlin, D. Bowers, William E. Scott, David R. Sherrod, James W. VallanceEmplacement of a silicic lava dome through a crater glacier: Mount St Helens, 2004-06
The process of lava-dome emplacement through a glacier was observed for the first time after Mount St Helens reawakened in September 2004. The glacier that had grown in the crater since the cataclysmic 1980 eruption was split in two by the new lava dome. The two parts of the glacier were successively squeezed against the crater wall. Photography, photogrammetry and geodetic measurements document gAuthorsJoseph S. Walder, Richard G. Lahusen, James W. Vallance, Steve P. SchillingTephra deposits for the past 2600 years from Irazú Volcano, Costa Rica: Chapter 12 in Volcanic hazards in Central America
No abstract available.AuthorsS.K. Clark, M. K. Reagan, D.A. Trimble
*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