John S. Pallister (Former Employee)
Science and Products
Filter Total Items: 53
Faulting 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 fi
Authors
John S. Pallister, Katharine V. Cashman, Jonathan T. Hagstrum, Nicholas M. Beeler, Seth C. Moran, Roger P. Denlinger
The Chaitén rhyolite lava dome: Eruption sequence, lava dome volumes, rapid effusion rates and source of the rhyolite magma
We use geologic field mapping and sampling, photogrammetric analysis of oblique aerial photographs, and digital elevation models to document the 2008-2009 eruptive sequence at Chaitén Volcano and to estimate volumes and effusion rates for the lava dome. We also present geochemical and petrologic data that contribute to understanding the source of the rhyolite and its unusually rapid effusion rates
Authors
John S. Pallister, Angela K. Diefenbach, William C. Burton, Jorge Munoz, Julia P. Griswold, Luis E. Lara, Jacob B. Lowenstern, Carolina E. Valenzuela
The 2010 explosive eruption of Java's Merapi volcano—A ‘100-year’ event
Merapi volcano (Indonesia) is one of the most active and hazardous volcanoes in the world. It is known for frequent small to moderate eruptions, pyroclastic flows produced by lava dome collapse, and the large population settled on and around the flanks of the volcano that is at risk. Its usual behavior for the last decades abruptly changed in late October and early November 2010, when the volcano
Authors
Surono, Philippe Jousset, John S. Pallister, Marie Boichu, M. Fabrizia Buongiorno, Agus Budisantoso, Fidel Costa, Supriyati Andreastuti, Fred Prata, David J. Schneider, Lieven Clarisse, Hanik Humaida, Sri Sumarti, Christian Bignami, Julia P. Griswold, Simon A. Carn, Clive Oppenheimer, Franck Lavigne
Interdisciplinary studies of eruption at Chaitén volcano, Chile
High-silica rhyolite magma fuels Earth's largest and most explosive eruptions. Recurrence intervals for such highly explosive eruptions are in the 100- to 100,000-year time range, and there have been few direct observations of such eruptions and their immediate impacts. Consequently, there was keen interest within the volcanology community when the first large eruption of high-silica rhyolite sinc
Authors
John S. Pallister, Jon J. Major, Thomas C. Pierson, Richard P. Holitt, Jacob B. Lowenstern, John C. Eichelberger, Lara Luis, Hugo Moreno, Jorge Muñoz, Jonathan M. Castro, Andrés Iroumé, Andrea Andreoli, Julia Jones, Fred Swanson, Charlie Crisafulli
Volcano monitoring
Volcanoes are not randomly distributed over the Earth's surface. Most are concentrated on the edges of continents, along island chains, or beneath the sea where they form long mountain ranges. More than half of the world's active volcanoes above sea level encircle the Pacific Ocean (see Fig. 1). The concept of plate tectonics explains the locations of volcanoes and their relationship to other larg
Authors
James G. Smith, Jonathan Dehn, Richard P. Hoblitt, Richard G. Lahusen, Jacob B. Lowenstern, Seth C. Moran, Lindsay McClelland, Kenneth A. McGee, Manuel Nathenson, Paul G. Okubo, John S. Pallister, Michael P. Poland, John A. Power, David J. Schneider, Thomas W. Sisson
Catalog of Mount St. Helens 2004 - 2005 tephra samples with major- and trace-element geochemistry
This open-file report presents a catalog of information about 135 ash samples along with geochemical analyses of bulk ash, glass and individual mineral grains from tephra deposited as a result of volcanic activity at Mount St. Helens, Washington, from October 1, 2004 until August 15, 2005. This data, in conjunction with that in a companion report on 2004-2007 Mount St. Helens dome samples by Thorn
Authors
Michael C. Rowe, Carl R. Thornber, Daniel J. Gooding, John S. Pallister
Catalog of Mount St. Helens 2004-2007 dome samples with major- and trace-element chemistry
Sampling and analysis of eruptive products at Mount St. Helens is an integral part of volcano monitoring efforts conducted by the U.S. Geological Survey?s Cascades Volcano Observatory (CVO). The objective of our eruption sampling program is to enable petrological assessments of pre-eruptive magmatic conditions, critical for ascertaining mechanisms for eruption triggering and forecasting potential
Authors
Carl R. Thornber, John S. Pallister, Michael C. Rowe, Siobhan McConnell, Trystan M. Herriott, Alison Eckberg, Winston C. Stokes, Diane Johnson Cornelius, Richard M. Conrey, Tammy Hannah, Joseph E. Taggart, Monique Adams, Paul J. Lamothe, James R. Budahn, Charles M. Knaack
Timing of degassing and plagioclase growth in lavas erupted from Mount St. Helens, 2004-2005, from 210Po-210Pb-226Ra disequilibria
Disequilibrium between 210Po, 210Pb, and 226Ra was
measured on rocks and plagioclase mineral separates erupted
during the first year of the ongoing eruption of Mount St.
Helens. The purpose of this study was to monitor the volatile
fluxing and crystal growth that occurred in the weeks, years,
and decades leading up to eruption. Whole-rock samples were
leached in dilute HCl to remove 210Po pr
Authors
Mark K. Reagan, Kari M. Cooper, John S. Pallister, Carl R. Thornber, Matthew Wortel
Plagioclase populations and zoning in dacite of the 2004-2005 Mount St. Helens eruption: Constraints for magma origin and dynamics
We investigated plagioclase phenocrysts in dacite of the
2004-5 eruption of Mount St. Helens to gain insights into the
magmatic processes of the current eruption, which is characterized by prolonged, nearly solid-state extrusion, low gas
emission, and shallow seismicity. In addition, we investigated
plagioclase of 1980-86 dacite.
Light and Nomarski microscopy were used to texturally
character
Authors
Martin J. Streck, Cindy A. Broderick, Carl R. Thronber, Michael A. Clynne, John S. Pallister
Trace element and Pb isotope composition of plagioclase from dome samples from the 2004-2005 eruption of Mount St. Helens, Washington
We report the results of in-situ laser ablation ICP–MS
analyses of anorthite content, trace-element (Li, Ti, Sr, Ba, La,
Pr, Ce, Nd, Eu, Pb) concentrations, and Pb-isotope compositions
in plagioclase from eight dome-dacite samples collected from
the 2004-5 eruption of Mount St. Helens and, for comparison,
from three dome samples from 1981-85. For 2004-5 samples,
plagioclase phenocrysts range
Authors
Adam J. R. Kent, Michael C. Rowe, Carl R. Thornber, John S. Pallister
From dome to dust: shallow crystallization and fragmentation of conduit magma during the 2004-2006 dome extrusion of Mount St. Helens, Washington
An unusual feature of the 2004-6 eruptive activity of
Mount St. Helens has been the continuous growth of successive spines that are mantled by thick fault gouge. Fault gouge
formation requires, first, solidification of ascending magma
within the conduit, then brittle fragmentation and cataclastic
flow. We document these processes through field relations,
hand samples, and thin-section texture
Authors
Katharine V. Cashman, Carl R. Thornber, John S. Pallister
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
Science and Products
Filter Total Items: 53
Faulting 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 fi
Authors
John S. Pallister, Katharine V. Cashman, Jonathan T. Hagstrum, Nicholas M. Beeler, Seth C. Moran, Roger P. Denlinger
The Chaitén rhyolite lava dome: Eruption sequence, lava dome volumes, rapid effusion rates and source of the rhyolite magma
We use geologic field mapping and sampling, photogrammetric analysis of oblique aerial photographs, and digital elevation models to document the 2008-2009 eruptive sequence at Chaitén Volcano and to estimate volumes and effusion rates for the lava dome. We also present geochemical and petrologic data that contribute to understanding the source of the rhyolite and its unusually rapid effusion rates
Authors
John S. Pallister, Angela K. Diefenbach, William C. Burton, Jorge Munoz, Julia P. Griswold, Luis E. Lara, Jacob B. Lowenstern, Carolina E. Valenzuela
The 2010 explosive eruption of Java's Merapi volcano—A ‘100-year’ event
Merapi volcano (Indonesia) is one of the most active and hazardous volcanoes in the world. It is known for frequent small to moderate eruptions, pyroclastic flows produced by lava dome collapse, and the large population settled on and around the flanks of the volcano that is at risk. Its usual behavior for the last decades abruptly changed in late October and early November 2010, when the volcano
Authors
Surono, Philippe Jousset, John S. Pallister, Marie Boichu, M. Fabrizia Buongiorno, Agus Budisantoso, Fidel Costa, Supriyati Andreastuti, Fred Prata, David J. Schneider, Lieven Clarisse, Hanik Humaida, Sri Sumarti, Christian Bignami, Julia P. Griswold, Simon A. Carn, Clive Oppenheimer, Franck Lavigne
Interdisciplinary studies of eruption at Chaitén volcano, Chile
High-silica rhyolite magma fuels Earth's largest and most explosive eruptions. Recurrence intervals for such highly explosive eruptions are in the 100- to 100,000-year time range, and there have been few direct observations of such eruptions and their immediate impacts. Consequently, there was keen interest within the volcanology community when the first large eruption of high-silica rhyolite sinc
Authors
John S. Pallister, Jon J. Major, Thomas C. Pierson, Richard P. Holitt, Jacob B. Lowenstern, John C. Eichelberger, Lara Luis, Hugo Moreno, Jorge Muñoz, Jonathan M. Castro, Andrés Iroumé, Andrea Andreoli, Julia Jones, Fred Swanson, Charlie Crisafulli
Volcano monitoring
Volcanoes are not randomly distributed over the Earth's surface. Most are concentrated on the edges of continents, along island chains, or beneath the sea where they form long mountain ranges. More than half of the world's active volcanoes above sea level encircle the Pacific Ocean (see Fig. 1). The concept of plate tectonics explains the locations of volcanoes and their relationship to other larg
Authors
James G. Smith, Jonathan Dehn, Richard P. Hoblitt, Richard G. Lahusen, Jacob B. Lowenstern, Seth C. Moran, Lindsay McClelland, Kenneth A. McGee, Manuel Nathenson, Paul G. Okubo, John S. Pallister, Michael P. Poland, John A. Power, David J. Schneider, Thomas W. Sisson
Catalog of Mount St. Helens 2004 - 2005 tephra samples with major- and trace-element geochemistry
This open-file report presents a catalog of information about 135 ash samples along with geochemical analyses of bulk ash, glass and individual mineral grains from tephra deposited as a result of volcanic activity at Mount St. Helens, Washington, from October 1, 2004 until August 15, 2005. This data, in conjunction with that in a companion report on 2004-2007 Mount St. Helens dome samples by Thorn
Authors
Michael C. Rowe, Carl R. Thornber, Daniel J. Gooding, John S. Pallister
Catalog of Mount St. Helens 2004-2007 dome samples with major- and trace-element chemistry
Sampling and analysis of eruptive products at Mount St. Helens is an integral part of volcano monitoring efforts conducted by the U.S. Geological Survey?s Cascades Volcano Observatory (CVO). The objective of our eruption sampling program is to enable petrological assessments of pre-eruptive magmatic conditions, critical for ascertaining mechanisms for eruption triggering and forecasting potential
Authors
Carl R. Thornber, John S. Pallister, Michael C. Rowe, Siobhan McConnell, Trystan M. Herriott, Alison Eckberg, Winston C. Stokes, Diane Johnson Cornelius, Richard M. Conrey, Tammy Hannah, Joseph E. Taggart, Monique Adams, Paul J. Lamothe, James R. Budahn, Charles M. Knaack
Timing of degassing and plagioclase growth in lavas erupted from Mount St. Helens, 2004-2005, from 210Po-210Pb-226Ra disequilibria
Disequilibrium between 210Po, 210Pb, and 226Ra was
measured on rocks and plagioclase mineral separates erupted
during the first year of the ongoing eruption of Mount St.
Helens. The purpose of this study was to monitor the volatile
fluxing and crystal growth that occurred in the weeks, years,
and decades leading up to eruption. Whole-rock samples were
leached in dilute HCl to remove 210Po pr
Authors
Mark K. Reagan, Kari M. Cooper, John S. Pallister, Carl R. Thornber, Matthew Wortel
Plagioclase populations and zoning in dacite of the 2004-2005 Mount St. Helens eruption: Constraints for magma origin and dynamics
We investigated plagioclase phenocrysts in dacite of the
2004-5 eruption of Mount St. Helens to gain insights into the
magmatic processes of the current eruption, which is characterized by prolonged, nearly solid-state extrusion, low gas
emission, and shallow seismicity. In addition, we investigated
plagioclase of 1980-86 dacite.
Light and Nomarski microscopy were used to texturally
character
Authors
Martin J. Streck, Cindy A. Broderick, Carl R. Thronber, Michael A. Clynne, John S. Pallister
Trace element and Pb isotope composition of plagioclase from dome samples from the 2004-2005 eruption of Mount St. Helens, Washington
We report the results of in-situ laser ablation ICP–MS
analyses of anorthite content, trace-element (Li, Ti, Sr, Ba, La,
Pr, Ce, Nd, Eu, Pb) concentrations, and Pb-isotope compositions
in plagioclase from eight dome-dacite samples collected from
the 2004-5 eruption of Mount St. Helens and, for comparison,
from three dome samples from 1981-85. For 2004-5 samples,
plagioclase phenocrysts range
Authors
Adam J. R. Kent, Michael C. Rowe, Carl R. Thornber, John S. Pallister
From dome to dust: shallow crystallization and fragmentation of conduit magma during the 2004-2006 dome extrusion of Mount St. Helens, Washington
An unusual feature of the 2004-6 eruptive activity of
Mount St. Helens has been the continuous growth of successive spines that are mantled by thick fault gouge. Fault gouge
formation requires, first, solidification of ascending magma
within the conduit, then brittle fragmentation and cataclastic
flow. We document these processes through field relations,
hand samples, and thin-section texture
Authors
Katharine V. Cashman, Carl R. Thornber, John S. Pallister
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