Publications
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Paleoceanographic history of the Guaymas Basin, Gulf of California, during the past 15,000 years based on diatoms, silicoflagellates, and biogenic sediments Paleoceanographic history of the Guaymas Basin, Gulf of California, during the past 15,000 years based on diatoms, silicoflagellates, and biogenic sediments
High-resolution records of calcium carbonate, biogenic opal, diatoms, and silicoflagellates from western Guaymas Basin gravity core GGC55 and piston core JPC56 and eastern Guaymas Basin DSDP Site 480 reveal a complex paleoceanographic history of the central Gulf of California during the past 15,000 years. Prior to ∼ 6.2 ka, the eastern and western Guaymas Basin proxy records were...
Authors
John A. Barron, David Bukry, Walter E. Dean
Volcano hazards Volcano hazards
Not only do “Volcanoes assail the senses …” (Decker and Decker, 1997, p. vii), but they also assail the environment when they erupt, terrifying and fascinating humankind for countless millennia. Volcanic processes and products – beneficial and hazardous – have profoundly impacted and continue to impact society (Chester, 1993, Chapter 14, this volume). It is estimated that about 10% of...
Authors
Robert I. Tilling
Hawaiian Volcano Observatory seismic data, January to December 2004 Hawaiian Volcano Observatory seismic data, January to December 2004
The Hawaiian Volcano Observatory (HVO) summary presents seismic data gathered during the year. The seismic summary is offered without interpretation as a source of preliminary data. It is complete in the sense that most data for events of M≥1.5 routinely gathered by the Observatory are included. The HVO summaries have been published in various forms since 1956. Summaries prior to 1974...
Authors
Jennifer S. Nakata
New constraints on mechanisms of remotely triggered seismicity at Long Valley Caldera New constraints on mechanisms of remotely triggered seismicity at Long Valley Caldera
Regional-scale triggering of local earthquakes in the crust by seismic waves from distant main shocks has now been robustly documented for over a decade. Some of the most thoroughly recorded examples of repeated triggering of a single site from multiple, large earthquakes are measured in geothermal fields of the western United States like Long Valley Caldera. As one of the few natural...
Authors
E. E. Brodsky, S. G. Prejean
Contemporaneous trachyandesitic and calc-alkaline volcanism of the Huerto Andesite, San Juan Volcanic Field, Colorado, USA Contemporaneous trachyandesitic and calc-alkaline volcanism of the Huerto Andesite, San Juan Volcanic Field, Colorado, USA
Locally, voluminous andesitic volcanism both preceded and followed large eruptions of silicic ash-flow tuff from many calderas in the San Juan volcanic field. The most voluminous post-collapse lava suite of the central San Juan caldera cluster is the 28 Ma Huerto Andesite, a diverse assemblage erupted from at least 5–6 volcanic centres that were active around the southern margins of the...
Authors
F. Parat, M.A. Dungan, P. W. Lipman
Surficial geologic tools in fluvial geomorphology: chapter 2 Surficial geologic tools in fluvial geomorphology: chapter 2
No abstract available.
Authors
Robert B. Jacobson, James E. O'Connor, Takashi Oguchi
Anatahan, Northern Mariana Islands: Reconnaissance geological observations during and after the volcanic crisis of spring 1990, and monitoring prior to the May 2003 eruption Anatahan, Northern Mariana Islands: Reconnaissance geological observations during and after the volcanic crisis of spring 1990, and monitoring prior to the May 2003 eruption
Anatahan island is 9.5 km east–west by 3.5 km north–south and truncated by an elongate caldera 5 km east–west by 2.5 km north–south. A steep-walled pit crater ∼1 km across and ∼200 m deep occupies the eastern part of the caldera. The island is the summit region of a mostly submarine stratovolcano. The oldest subaerial rocks (stage 1) are exposed low on the outer flanks and in the caldera...
Authors
S.K. Rowland, J. P. Lockwood, F. A. Trusdell, R. B. Moore, M. K. Sako, R. Y. Koyanagi, G. Kojima
Assembling an ignimbrite: Compositionally defined eruptive packages in the 1912 Valley of Ten Thousand Smokes ignimbrite, Alaska Assembling an ignimbrite: Compositionally defined eruptive packages in the 1912 Valley of Ten Thousand Smokes ignimbrite, Alaska
The 1912 Valley of Ten Thousand Smokes (VTTS) ignimbrite was constructed from 9 compositionally distinct, sequentially emplaced packages, each with distinct proportions of rhyolite (R), dacite (D), and andesite (A) pumices that permit us to map package boundaries and flow paths from vent to distal extents. Changing pumice proportions and interbedding relationships link ignimbrite...
Authors
J. Fierstein, C. J. N. Wilson
Mount St. Helens erupts again: Activity from September 2004 through March 2005 Mount St. Helens erupts again: Activity from September 2004 through March 2005
Eruptive activity at Mount St. Helens captured the world’s attention in 1980 when the largest historical landslide on Earth and a powerful explosion reshaped the volcano, created its distinctive crater, and dramatically modified the surrounding landscape. Over the next 6 years, episodic extrusions of lava built a large dome in the crater. From 1987 to 2004, Mount St. Helens returned to a...
Authors
Jon J. Major, William E. Scott, Carolyn Driedger, Dan Dzurisin
Argon dating at and near Medicine Lake volcano, California: Results and data Argon dating at and near Medicine Lake volcano, California: Results and data
No abstract available.
Authors
Julie M. Donnelly-Nolan, Marvin A. Lanphere
A comparison of seismic event detection with IASPEI and earthworm acquisition systems at Alaskan volcanoes A comparison of seismic event detection with IASPEI and earthworm acquisition systems at Alaskan volcanoes
Since 1988, Alaska Volcano Observatory (AVO) has been continually monitoring seismicity at active volcanoes in Alaska (Dixon et al., 2004). The AVO seismic network has grown from 27 stations on the Cook Inlet volcanoes (Augustine, Iliamna, Redoubt, and Spurr) to 160 stations on 27 volcanoes in 2004 (Figure 1). Each seismograph subnetwork on an individual volcano typically consists of...
Authors
James P. Dixon, John A. Power, Scott D. Stihler
DUCKS: Low cost thermal monitoring units for near-vent deployment DUCKS: Low cost thermal monitoring units for near-vent deployment
During 1999 we designed and tested a thermal monitoring system to provide a cheap, robust, modular, real-time system capable of surviving the hostile conditions encountered proximal to active volcanic vents. In November 2000 the first system was deployed at Pu'u 'O'o (Kilauea, Hawai'i) to target persistently active vents. Aside from some minor problems, such as sensor damage due to...
Authors
A. Harris, D. Pirie, K. Horton, H. Garbeil, E. Pilger, H. Ramm, R. Hoblitt, C. Thornber, M. Ripepe, E. Marchetti, P. Poggi