Publications
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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
The ongoing Pu'u 'O'o-Kupaianaha eruption of Kilauea Volcano, Hawai'i The ongoing Pu'u 'O'o-Kupaianaha eruption of Kilauea Volcano, Hawai'i
No abstract available.
Authors
Christina Heliker, Steven R. Brantley
Comments on potential geologic and seismic hazards affecting coastal Ventura County, California Comments on potential geologic and seismic hazards affecting coastal Ventura County, California
This report examines the regional seismic and geologic hazards that could affect proposed liquefied natural gas (LNG) facilities in coastal Ventura County, California. Faults throughout this area are thought to be capable of producing earthquakes of magnitude 6.5 to 7.5, which could produce surface fault offsets of as much as 15 feet. Many of these faults are sufficiently well understood...
Authors
Stephanie L. Ross, David M. Boore, Michael A. Fisher, Arthur D. Frankel, Eric L. Geist, Kenneth W. Hudnut, Robert E. Kayen, Homa J. Lee, William R. Normark, Florence L. Wong
Icelandic analogs to Martian flood lavas Icelandic analogs to Martian flood lavas
We report on new field observations from Icelandic lava flows that have the same surface morphology as many Martian flood lava flows. The Martian flood lavas are characterized by a platy‐ridged surface morphology whose formation is not well understood. The examples on Mars include some of the most pristine lava on the planet and flows >1500 km long. The surfaces of the flows are...
Authors
Laszlo P. Keszthelyi, Thorvaldur Thordarson, Alfred McEwen, Henning Haack, Marie-Noelle Guilbaud, Stephen Self, Matti J. Rossi
Geodetic and seismic constraints on some seismogenic zone processes in Costa Rica Geodetic and seismic constraints on some seismogenic zone processes in Costa Rica
New seismic and geodetic data from Costa Rica provide insight into seismogenic zone processes in Central America, where the Cocos and Caribbean plates converge. Seismic data are from combined land and ocean bottom deployments in the Nicoya peninsula in northern Costa Rica and near the Osa peninsula in southern Costa Rica. In Nicoya, inversion of GPS data suggests two locked patches...
Authors
E. Norabuena, Timothy Dixon, Susan Schwartz, Heather DeShon, Andrew Newman, Marino Protti, Victor Gonzalez, LeRoy Dorman, Ernst Flueh, Paul Lundgren, Frederick Pollitz, Dan Sampson
RADAR: The Cassini Titan Radar Mapper RADAR: The Cassini Titan Radar Mapper
The Cassini RADAR instrument is a multimode 13.8 GHz multiple-beam sensor that can operate as a synthetic-aperture radar (SAR) imager, altimeter, scatterometer, and radiometer. The principal objective of the RADAR is to map the surface of Titan. This will be done in the imaging, scatterometer, and radiometer modes. The RADAR altimeter data will provide information on relative elevations...
Authors
C. Elachi, M.D. Allison, L. Borgarelli, P. Encrenaz, E. Im, M.A. Janssen, W.T.K. Johnson, Randolph L. Kirk, R. D. Lorenz, J. I. Lunine, D.O. Muhleman, S.J. Ostro, G. Picardi, F. Posa, C.G. Rapley, L.E. Roth, R. Seu, Laurence A. Soderblom, S. Vetrella, S. D. Wall, C. A. Wood, H. A. Zebker