Publications
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What are volcano hazards?
Volcanoes give rise to numerous geologic and hydrologic hazards. U.S. Geological Survey (USGS) scientists are assessing hazards at many of the almost 70 active and potentially active volcanoes in the United States. They are closely monitoring activity at the most dangerous of these volcanoes and are prepared to issue warnings of impending eruptions or other hazardous events.
Authors
Bobbie Myers, Steven R. Brantley, Peter R. Stauffer, James W. Hendley
Volcano hazards in the Mount Hood region, Oregon
Mount Hood is a potentially active volcano close to rapidly growing communities and recreation areas. The most likely widespread and hazardous consequence of a future eruption will be for lahars (rapidly moving mudflows) to sweep down the entire length of the Sandy (including the Zigzag) and White River valleys. Lahars can be generated by hot volcanic flows that melt snow and ice or by landslides
Authors
W. E. Scott, T. C. Pierson, S. P. Schilling, J. E. Costa, C. A. Gardner, J. W. Vallance, J. J. Major
Living on active volcanoes - The Island of Hawai'i
People on the Island of Hawai'i face many hazards that come with living on or near active volcanoes. These include lava flows, explosive eruptions, volcanic smog, damaging earthquakes, and tsunamis (giant seawaves). As the population of the island grows, the task of reducing the risk from volcano hazards becomes increasingly difficult. To help protect lives and property, U.S. Geological Survey (US
Authors
Christina Heliker, Peter H. Stauffer, James W. Hendley
Living on active volcanoes: The Island of Hawai'i
No abstract available.
Authors
Christina Heliker, Peter H. Stauffer, James W. Hendley
Primitive magmas at five Cascade volcanic fields: Melts from hot, heterogeneous sub-arc mantle
Major and trace element concentrations, including REE by isotope dilution, and Sr, Nd, Pb, and O isotope ratios have been determined for 38 mafic lavas from the Mount Adams, Crater Lake, Mount Shasta, Medicine Lake, and Lassen volcanic fields, in the Cascade arc, northwestern part of the United States. Many of the samples have a high Mg# [100Mg/(Mg + FeT) > 60] and Ni content (>140 ppm) such that
Authors
C. R. Bacon, P. E. Bruggman, R. L. Christiansen, M.A. Clynne, J. M. Donnelly-Nolan, W. Hildreth
Debris-flow mobilization from landslides
Field observations, laboratory experiments, and theoretical analyses indicate that landslides mobilize to form debris flows by three processes: (a) widespread Coulomb failure within a sloping soil, rock, or sediment mass, (b) partial or complete liquefaction of the mass by high pore-fluid pressures, and (c) conversion of landslide translational energy to internal vibrational energy (i.e. granular
Authors
Richard M. Iverson, Mark E. Reid, Richard G. Lahusen
Imaging the crustal magma sources beneath Mauna Loa and Kilauea volcanoes, Hawaii
Three-dimensional seismic P-wave traveltime tomography is used to image the magma sources beneath Mauna Loa and Kilauea volcanoes, Hawaii. High-velocity bodies (>6.4 km/s) in the upper 9 km of the crust beneath the summits and rift zones of the volcanoes correlate with zones of high magnetic intensities and are interpreted as solidified gabbro-ultramafic cumulates from which the surface volcanism
Authors
Paul G. Okubo, Harley M. Benz, Bernard A. Chouet
Magmatic processes that generated the rhyolite of Glass Mountain, Medicine Lake volcano, N. California
Glass Mountain consists of a 1 km3, compositionally zoned rhyolite to dacite glass flow containing magmatic inclusions and xenoliths of underlying shallow crust. Mixing of magmas produced by fractional crystallization of andesite and crustal melting generated the rhyolite of Glass Mountain. Melting experiments were carried out on basaltic andesite and andesite magmatic inclusions at 100, 150 and 2
Authors
Timothy L. Grove, Julie Donnelly-Nolan, T. Housh
Preliminary Volcano-Hazard Assessment for Redoubt Volcano, Alaska
Redoubt Volcano is a stratovolcano located within a few hundred kilometers of more than half of the population of Alaska. This volcano has erupted explosively at least six times since historical observations began in 1778. The most recent eruption occurred in 1989-90 and similar eruptions can be expected in the future. The early part of the 1989-90 eruption was characterized by explosive emission
Authors
Christopher F. Waythomas, Joseph M. Dorava, Thomas P. Miller, Christina A. Neal, Robert G. McGimsey
Volcanic ash - danger to aircraft in the north Pacific
The world's busy air traffic corridors pass over hundreds of volcanoes capable of sudden, explosive eruptions. In the United States alone, aircraft carry many thousands of passengers and millions of dollars of cargo over volcanoes each day. Volcanic ash can be a serious hazard to aviation even thousands of miles from an eruption. Airborne ash can diminish visibility, damage flight control systems,
Authors
Christina A. Neal, Thomas J. Casadevall, Thomas P. Miller, James W. Hendley, Peter H. Stauffer
Volcano and earthquake hazards in the Crater Lake region, Oregon
Crater Lake lies in a basin, or caldera, formed
by collapse of the Cascade volcano known as Mount
Mazama during a violent, climactic eruption about
7,700 years ago. This event dramatically changed the
character of the volcano so that many potential types
of future events have no precedent there. This
potentially active volcanic center is contained within
Crater Lake National Park, visited b
Authors
Charles R. Bacon, Larry G. Mastin, Kevin M. Scott, Manuel Nathenson
Lahars of Mount Pinatubo, Philippines
On June 15, 1991, Mount Pinatubo in the Philippines exploded in the second largest volcanic eruption on Earth this century. This eruption deposited more than 1 cubic mile (5 cubic kilometers) of volcanic ash and rock fragments on the volcano's slopes. Within hours, heavy rains began to wash this material down into the surrounding lowlands in giant, fast-moving mudflows called lahars. In the next f
Authors
Christopher G. Newhall, Peter H. Stauffer, James W. Hendley