Publications
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2003 volcanic activity in Alaska and Kamchatka: Summary of events and response of the Alaska Volcano Observatory 2003 volcanic activity in Alaska and Kamchatka: Summary of events and response of the Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) monitors the more than 40 historically active volcanoes of the Aleutian Arc. Of these, 24 were considered monitored in real time with short-period seismic instrument networks as of the end of 2003. The AVO core monitoring program also includes daily analysis of satellite imagery, observation over flights, and compilation of pilot reports and reports...
Authors
Robert G. McGimsey, Christina A. Neal, Olga Girina
Models of lithosphere and asthenosphere anisotropic structure of the Yellowstone hot spot from shear wave splitting Models of lithosphere and asthenosphere anisotropic structure of the Yellowstone hot spot from shear wave splitting
Teleseismic shear wave splitting measured at 56 continuous and temporary seismographs deployed in a 500 km by 600 km area around the Yellowstone hot spot indicates that fast anisotropy in the mantle is parallel to the direction of plate motion under most of the array. The average split time from all stations of 0.9 s is typical of continental stations. There is little evidence for plume...
Authors
Gregory P. Waite, D.L. Schutt, Robert B. Smith
The 2003 eruption of Anatahan volcano, Commonwealth of the Northern Mariana Islands: Chronology, volcanology, and deformation The 2003 eruption of Anatahan volcano, Commonwealth of the Northern Mariana Islands: Chronology, volcanology, and deformation
The first historical eruption on Anatahan Island occurred on 10 May 2003 from the east crater of the volcano. The eruption was preceded by several hours of seismicity. Two and a half hours before the outbreak, the number of earthquakes surged to more than 100 events per hour. At 0730 UTC, the Washington Volcanic Ash Advisory Center issued an ash advisory. Although the eruption lasted for...
Authors
F. A. Trusdell, R. B. Moore, M. Sako, R.A. White, S.K. Koyanagi, R. Chong, J.T. Camacho
Pitted cones and domes on Mars: Observations in Acidalia Planitia and Cydonia Mensae using MOC, THEMIS, and TES data Pitted cones and domes on Mars: Observations in Acidalia Planitia and Cydonia Mensae using MOC, THEMIS, and TES data
Domes and cones with summit pits located in Acidalia Planitia and Cydonia Mensae were studied using MOC and THEMIS images and a TES‐derived thermal inertia map. North of 40.5°N latitude, the features have a dome‐like morphology, and south of that latitude, the morphology is more cone‐like. Layering is apparent in the summit craters of fresher looking southern cones, and asymmetric aprons...
Authors
William H. Farrand, Lisa R. Gaddis, Laszlo P. Keszthelyi
Hazard calculations for the WGCEP-2002 earthquake forecast using OpenSHA and distributed object technologies Hazard calculations for the WGCEP-2002 earthquake forecast using OpenSHA and distributed object technologies
We present seismic-hazard calculations for what is arguably the most sophisticated earthquake forecast ever developed—the model by the 2002 Working Group on California Earthquake Probabilities (2003), or WGCEP-2002 as referred to hereafter. These calculations have been made possible by developments in both OpenSHA (Field et al., 2003) and the Information Technology Research (ITR)...
Authors
Edward H. Field, N. Gupta, Vipin Gupta, Michael L. Blanpied, Phillip J. Maechling, Thomas H. Jordan
Interferometric synthetic aperture radar study of Okmok volcano, Alaska, 1992-2003: Magma supply dynamics and postemplacement lava flow deformation Interferometric synthetic aperture radar study of Okmok volcano, Alaska, 1992-2003: Magma supply dynamics and postemplacement lava flow deformation
Okmok volcano, located in the central Aleutian arc, Alaska, is a dominantly basaltic complex topped with a 10-km-wide caldera that formed circa 2.05 ka. Okmok erupted several times during the 20th century, most recently in 1997; eruptions in 1945, 1958, and 1997 produced lava flows within the caldera. We used 80 interferometric synthetic aperture radar (InSAR) images (interferograms) to...
Authors
Z. Lu, Timothy Masterlark, Daniel Dzurisin
Albedo of the south pole on Mars determined by topographic forcing of atmosphere dynamics Albedo of the south pole on Mars determined by topographic forcing of atmosphere dynamics
The nature of the martian south polar cap has remained enigmatic since the first spacecraft observations. In particular, the presence of a perennial carbon dioxide ice cap, the formation of a vast area of black ‘slab ice’ known as the Cryptic region and the asymmetric springtime retreat of the cap have eluded explanation. Here we present observations and climate modelling that indicate...
Authors
Anthony Colaprete, Jeffrey R. Barnes, Robert M. Haberle, Jeffery L. Hollingsworth, Hugh H. Kieffer, Timothy N. Titus
Rainfall-induced landslides in Puerto Rico: An overview Rainfall-induced landslides in Puerto Rico: An overview
Rainfall-induced landslides are common in Puerto Rico (PR). The presence of steep slopes in mountainous terrain, coupled with weathered soils and intense rainfall, leads to severe slope-stability problems throughout the island. Episodic triggering events such as hurricanes and earthquakes further exacerbate these problems. All physiographic provinces of the island have experienced...
Authors
M.A. Pando, M.E. Ruiz, M. C. Larsen
Degassing Lakes Nyos and Monoun: Defusing certain disaster Degassing Lakes Nyos and Monoun: Defusing certain disaster
Since the catastrophic releases of CO2 in the 1980s, Lakes Nyos and Monoun in Cameroon experienced CO2 recharge at alarming rates of up to 80 mol/m2 per yr. Total gas pressures reached 8.3 and 15.6 bar in Monoun (2003) and Nyos (2001), respectively, resulting in gas saturation levels up to 97%. These natural hazards are distinguished by the potential for mitigation to prevent future...
Authors
G.W. Kling, William C. Evans, G. Tanyileke, M. Kusakabe, T. Ohba, Y. Yoshida, J.V. Hell
The legacy of contaminated sediments in Boston Harbor The legacy of contaminated sediments in Boston Harbor
Scientists at the U.S. Geological Survey (USGS) have assembled a significant body of data that is now in a usable form. The USGS adopted an interdisciplinary approach to begin the pioneering effort at data rescue. This work involved collaboration with the Environmental Protection Agency (EPA), the U.S. Army Corps of Engineers (USACE), the Massachusetts Water Resources Authority (MWRA)
Authors
Frank T. Manheim
Book review: Earth’s magnetism in the age of sail Book review: Earth’s magnetism in the age of sail
For many centuries, the source, behavior, and even the essential nature of geomagnetism were enigmatic. Despite this, the effect of geomagnetism was familiar, by imparting a directional preference on the magnetized needle of the compass and providing a useful, if somewhat annoyingly complicated, reference for navigators. Although the compass seems to have first been invented in China, it...
Authors
Jeffrey J. Love
Evidence from Opportunity’s Microscopic Imager for water on Meridiani Planum Evidence from Opportunity’s Microscopic Imager for water on Meridiani Planum
The Microscopic Imager on the Opportunity rover analyzed textures of soils and rocks at Meridiani Planum at a scale of 31 micrometers per pixel. The uppermost millimeter of some soils is weakly cemented, whereas other soils show little evidence of cohesion. Rock outcrops are laminated on a millimeter scale; image mosaics of cross-stratification suggest that some sediments were deposited...
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. Bell, P. Bertelsen, B. L. Ehlmann, W. Farrand, Lisa R. Gaddis, R. Greeley, J. Grotzinger, A. G. Hayes, S.F. Hviid, J. R. Johnson, B. Jolliff, K.M. Kinch, A. H. Knoll, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, D. W. Ming, J. W. Rice, L. Richter, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, S. Thompson, T. Wdowiak, C. Weitz, P. Whelley