Publications
Filter Total Items: 2677
Chemical analyses and K-Ar ages of samples from 13 drill holes, Medicine Lake volcano, California
Chemical analyses and K-Ar ages are presented for rocks sampled from drill holes at Medicine Lake volcano, northern California. A location map and a cross-section are included, as are separate tables for drill hole information, major and trace element data, and for K-Ar dates.
Authors
Julie M. Donnelly-Nolan
USGS-NoGaDat - A global dataset of noble gas concentrations and their isotopic ratios in volcanic systems
The database (Version 1.0) is a MS-Excel file that contains close to 5,000 entries of published information on noble gas concentrations and isotopic ratios from volcanic systems in Mid-Ocean ridges, ocean islands, seamounts, and oceanic and continental arcs (location map). Where they were available we also included the isotopic ratios of strontium, neodymium, and carbon. The database is sub-divide
Authors
Atosa A. Abedini, S. Hurwitz, William C. Evans
Preface
No abstract available.
Authors
João Carlos Nunes, Robert I. Tilling, Gudmundur E. Sigvaldason
Dynamics of diffusive bubble growth and pressure recovery in a bubbly rhyolitic melt embedded in an elastic solid
We present a model of gas exsolution and bubble expansion in a melt supersaturated in response to a sudden pressure drop. In our model, the melt contains a suspension of gas bubbles of identical sizes and is encased in a penny-shaped crack embedded in an elastic solid. The suspension is modeled as a three-dimensional lattice of spherical cells with slight overlap, where each elementary cell consis
Authors
Bernard A. Chouet, Phillip B. Dawson, Masaru Nakano
Aftershock decay, productivity, and stress rates in Hawaii: Indicators of temperature and stress from magma sources
We examined dozens of aftershock sequences in Hawaii in terms of Gutenberg-Richter and modified Omori law parameters. We studied p, the rate of aftershock decay; Ap, the aftershock productivity, defined as the observed divided by the expected number of aftershocks; and c, the time delay when aftershock rates begin to fall. We found that for earthquakes shallower than 20 km, p values >1.2 are near
Authors
Fred W. Klein, Tom Wright, Jennifer Nakata
Borehole dilatometer installation, operation, and maintenance at sites in Hawaii
In response to concerns about the potential hazard of Mauna Loa volcano in Hawaii, the USGS began efforts in 1998 to add four high-resolution borehole sites. Located at these sites are; strainmeters, tiltmeters, seismometers, accelerometers and other instrumentation. These instruments are capable of providing continuous monitoring of the magma movement under Mauna Loa. Each site was planned to pro
Authors
G.D. Myren, M.J.S. Johnston, R.J. Mueller
Local infrasound observations of large ash explosions at Augustine Volcano, Alaska, during January 11–28, 2006
We present and interpret acoustic waveforms associated with a sequence of large explosion events that occurred during the initial stages of the 2006 eruption of Augustine Volcano, Alaska. During January 11–28, 2006, 13 large explosion events created ash-rich plumes that reached up to 14 km a.s.l., and generated atmospheric pressure waves that were recorded on scale by a microphone located at a dis
Authors
Tanja Petersen, Silvio De Angelis, Guy Tytgat, Stephen R. McNutt
Usoi Dam wave overtopping and flood routing in the Bartang and Panj Rivers, Tajikistan
The Usoi dam was created in the winter of 1911 after an enormous seismogenic rock slide completely blocked the valley of the Bartang River in the Pamir Mountains of southeastern Tajikistan. At present the dam impounds 17 million cubic meters of water in Lake Sarez.
Flood volume and discharge estimates were made for several landslide generated floods that could overtop the dam. For landslide vol
Authors
John Risley, Joseph Walder, Roger Denlinger
Publications of the Volcano Hazards Program 2004
The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity as funded by Congressional appropriation. Investigations are carried out in the Geology and Hydrology Disciplines of the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of Alaska Fairbanks Geophysical Institute, University of Ha
Authors
Manuel Nathenson
AMS Radiocarbon dating of paleosols intercalated with tephra layers from Mayon Volcano, southern Luzon, Philippines: A preliminary report
This paper presents the AMS 14C dates of paleosols intercalated with tephra layers in the vicinity of Mayon Volcano, southern Luzon, Philippines. the obtained 14C dates are almost consistent with the stratigraphy of the Mayon tephra group. On the basis of calibrated 14C age of soil layer directly overlying the lowest ash layer, the oldest eruptive event must have taken place shortly before 20 cal
Authors
Ma. Hannah T. Mirabueno, Mitsuru Okuno, Toshio Nakamura, Christopher G. Newhall, Tetsuo Kobayashi
InSAR captures rifting and volcanism in East Africa
In the past decade, synthetic aperture radar interferometric (InSAR) has enjoyed increasing use as a tool for detecting and characterizing surface deformation associated with volcanoes, earthquakes, glaciers, and other geological processes. Though InSAR can only image deformation that occurs along the radar line-of-sight and is subject to atmospheric, orbital, and other errors that can be difficul
Authors
Michael P. Poland
Downstream aggradation owing to lava dome extrusion and rainfall runoff at Volcán Santiaguito, Guatemala
Persistent lava extrusion at the Santiaguito dome complex (Guatemala) results in continuous lahar activity and river bed aggradation downstream of the volcano. We present a simple method that uses vegetation indices extracted from Landsat Thematic Mapper (TM) data to map impacted zones. Application of this technique to a time series of 21 TM images acquired between 1987 and 2000 allow us to map, m
Authors
Andrew J. L. Harris, James W. Vallance, Paul Kimberly, William I. Rose, Otoniel Matías, Elly Bunzendahl, Luke P. Flynn, Harold Garbeil