Publications
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Dam removal: Listening in Dam removal: Listening in
Dam removal is widely used as an approach for river restoration in the United States. The increase in dam removals—particularly large dams—and associated dam-removal studies over the last few decades motivated a working group at the USGS John Wesley Powell Center for Analysis and Synthesis to review and synthesize available studies of dam removals and their findings. Based on dam...
Authors
Melissa M. Foley, James Bellmore, James E. O'Connor, Jeffrey J. Duda, Amy E. East, Gordon G. Grant, Chauncey W. Anderson, Jennifer A. Bountry, Mathias J. Collins, Patrick J. Connolly, Laura S. Craig, James E. Evans, Samantha Greene, Francis J. Magilligan, Christopher S. Magirl, Jon J. Major, George R. Pess, Timothy J. Randle, Patrick B. Shafroth, Christian E. Torgersen, Desiree D. Tullos, Andrew C. Wilcox
By
Ecosystems Mission Area, Natural Hazards Mission Area, Water Resources Mission Area, Volcano Hazards Program, Forest and Rangeland Ecosystem Science Center, John Wesley Powell Center for Analysis and Synthesis, Oregon Water Science Center, Pacific Coastal and Marine Science Center, Volcano Science Center, Western Fisheries Research Center, Columbia River Research Laboratory (CRRL)
Volcanic cloud evolution: Characteristics, observational capabilities and challenges Volcanic cloud evolution: Characteristics, observational capabilities and challenges
Volcanic clouds composed of solid particles, volcanic gases, and related aerosols evolve from the time of eruption until the cloud constituents are removed from the atmosphere. While airborne, they have the potential to cause damage to aircraft, ranging from acute encounters that can lead to an immediate hazard to flight safety, to chronic wear on aircraft components, to benign...
Authors
David J. Schneider, Michael J. Pavolonis, Simon Carn
Field-trip guide to Columbia River flood basalts, associated rhyolites, and diverse post-plume volcanism in eastern Oregon Field-trip guide to Columbia River flood basalts, associated rhyolites, and diverse post-plume volcanism in eastern Oregon
The Miocene Columbia River Basalt Group (CRBG) is the youngest and best preserved continental flood basalt province on Earth, linked in space and time with a compositionally diverse succession of volcanic rocks that partially record the apparent emergence and passage of the Yellowstone plume head through eastern Oregon during the late Cenozoic. This compositionally diverse suite of...
Authors
Mark L. Ferns, Martin J. Streck, Jason D. McClaughry
Field-trip guide to the geologic highlights of Newberry Volcano, Oregon Field-trip guide to the geologic highlights of Newberry Volcano, Oregon
Newberry Volcano and its surrounding lavas cover about 3,000 square kilometers (km2) in central Oregon. This massive, shield-shaped, composite volcano is located in the rear of the Cascades Volcanic Arc, ~60 km east of the Cascade Range crest. The volcano overlaps the northwestern corner of the Basin and Range tectonic province, known locally as the High Lava Plains, and is strongly...
Authors
Robert A. Jensen, Julie M. Donnelly-Nolan
Geologic field trip guide to Mount Mazama and Crater Lake Caldera, Oregon Geologic field trip guide to Mount Mazama and Crater Lake Caldera, Oregon
Crater Lake partly fills one of the most spectacular calderas of the world—an 8 by 10 kilometer (km) basin more than 1 km deep formed by collapse of the Mount Mazama volcano during a rapid series of explosive eruptions ~7,700 years ago. Having a maximum depth of 594 meters (m), Crater Lake is the deepest lake in the United States. Crater Lake National Park, dedicated in 1902, encompasses...
Authors
Charles R. Bacon, Heather M. Wright
Oxygen and U-Th isotopes and the timescales of hydrothermal exchange and melting in granitoid wall rocks at Mount Mazama, Crater Lake, Oregon Oxygen and U-Th isotopes and the timescales of hydrothermal exchange and melting in granitoid wall rocks at Mount Mazama, Crater Lake, Oregon
We report new whole rock U-Th and in-situ oxygen isotope compositions for partially melted (0–50 vol% melt), low-δ18O Pleistocene granitoid blocks ejected during the ∼7.7 ka caldera-forming eruption of Mt. Mazama (Crater Lake, Oregon). The blocks are interpreted to represent wall rocks of the climactic magma chamber that, prior to eruption, experienced variable amounts of exchange with...
Authors
Meagan E. Ankney, Charles R. Bacon, John W. Valley, Brian L. Beard, Clark M. Johnson
Field-trip guide to Mount St. Helens, Washington - An overview of the eruptive history and petrology, tephra deposits, 1980 pyroclastic density current deposits, and the crater Field-trip guide to Mount St. Helens, Washington - An overview of the eruptive history and petrology, tephra deposits, 1980 pyroclastic density current deposits, and the crater
This field trip will provide an introduction to several fascinating features of Mount St. Helens. The trip begins with a rigorous hike of about 15 km from the Johnston Ridge Observatory (9 km north-northeast of the crater vent), across the 1980 Pumice Plain, to Windy Ridge (3.6 km northeast of the crater vent) to examine features that document the dynamics and progressive emplacement of
Authors
John S. Pallister, Michael A. Clynne, Heather M. Wright, Alexa R. Van Eaton, James W. Vallance, David R. Sherrod, B. Peter Kokelaar
Field-trip guide to a volcanic transect of the Pacific Northwest Field-trip guide to a volcanic transect of the Pacific Northwest
The Pacific Northwest region of the United States provides world-class and historically important examples of a wide variety of volcanic features. This guide is designed to give a broad overview of the region’s diverse volcanism rather than focusing on the results of detailed studies; the reader should consult the reference list for more detailed information on each of the sites, and we...
Authors
Dennis Geist, John A. Wolff, Karen Harpp
Initial pulse of Siberian Traps sills as the trigger of the end-Permian mass extinction Initial pulse of Siberian Traps sills as the trigger of the end-Permian mass extinction
Mass extinction events are short-lived and characterized by catastrophic biosphere collapse and subsequent reorganization. Their abrupt nature necessitates a similarly short-lived trigger, and large igneous province magmatism is often implicated. However, large igneous provinces are long-lived compared to mass extinctions. Therefore, if large igneous provinces are an effective trigger, a
Authors
Seth D. Burgess, James D. Muirhead, Samuel A. Bowring
Temporal variation of tectonic tremor activity in southern Taiwan around the 2010 ML6.4 Jiashian Earthquake Temporal variation of tectonic tremor activity in southern Taiwan around the 2010 ML6.4 Jiashian Earthquake
Deep tectonic tremor, which is extremely sensitive to small stress variations, could be used to monitor fault-zone processes during large earthquake cycles and aseismic processes before large earthquakes. In this study, we develop an algorithm for the automatic detection and location of tectonic tremor beneath the southern Central Range of Taiwan and examine the spatio-temporal...
Authors
Kevin Chao, Zhigang Peng, Ya-Ju Hsu, Kazushige Obara, Kuo-En Ching, Chunquan Wu, Hsin-Chieh Pu, Peih-Lin Leu, Aaron Wech
Geologic field-trip guide to Long Valley Caldera, California Geologic field-trip guide to Long Valley Caldera, California
This guide to the geology of Long Valley Caldera is presented in four parts: (1) An overview of the volcanic geology; (2) a chronological summary of the principal geologic events; (3) a road log with directions and descriptions for 38 field-trip stops; and (4) a summary of the geophysical unrest since 1978 and discussion of its causes. The sequence of stops is arranged as a four-day...
Authors
Wes Hildreth, Judy Fierstein
United States-Chile binational exchange for volcanic risk reduction, 2015—Activities and benefits United States-Chile binational exchange for volcanic risk reduction, 2015—Activities and benefits
In 2015, representatives from the United States and Chile exchanged visits to discuss and share their expertise and experiences dealing with volcano hazards. Communities in both countries are at risk from various volcano hazards. Risks to lives and property posed by these hazards are a function not only of the type and size of future eruptions but also of distances from volcanoes...
Authors
Thomas C. Pierson, Margaret T. Mangan, Luis E. Lara Pulgar, Alvaro Ramos Amigo