Publications
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Infrasonic ambient noise interferometry from correlations of microbaroms
We show that microbaroms, continuous infrasound fluctuations resulting from the interaction of the ocean with the atmosphere, have long-range correlation properties that make it possible to estimate the impulse response between two microphones from passive recordings. The processing is analogous to methods employed in the emerging field of ambient noise seismology, where the random noise source is
Authors
M.M. Haney
Objective rapid delineation of areas at risk from block-and-ash pyroclastic flows and surges
Assessments of pyroclastic flow (PF) hazards are commonly based on mapping of PF and surge deposits and estimations of inundation limits, and/or computer models of varying degrees of sophistication. In volcanic crises a PF hazard map may be sorely needed, but limited time, exposures, or safety aspects may preclude fieldwork, and insufficient time or baseline data may be available for reliable dyna
Authors
C. Widiwijayanti, B. Voight, D. Hidayat, S. P. Schilling
Geomagnetic observations on tristan da cunha, south atlantic ocean
Few geomagnetic ground observations exist of the Earth's strongest core field anomaly, the South Atlantic Anomaly (SAA). The geomagnetic repeat station on the island Tristan da Cunha, located half-way between South Africa and South America at 37?? 05' S, 12?? 18' W, is therefore of crucial importance. We have conducted several sets of repeat station measurements during magnetically quiet condition
Authors
J. Matzka, N. Olsen, C.F. Maule, L.W. Pedersen, A.M. Berarducci, S. Macmillan
Variations in population exposure and sensitivity to lahar hazards from Mount Rainier, Washington
Although much has been done to understand, quantify, and delineate volcanic hazards, there are fewer efforts to assess societal vulnerability to these hazards, particularly demographic differences in exposed populations or spatial variations in exposure to regional hazards. To better understand population diversity in volcanic hazard zones, we assess the number and types of people in a single type
Authors
N. Wood, C. Soulard
Diverse lavas from closely spaced volcanoes drawing from a common parent: Emmons Lake Volcanic Center, Eastern Aleutian Arc
Emmons Lake Volcanic Center (ELVC) on the lower Alaskan Peninsula is one of the largest and most diverse volcanic centers in the Aleutian Arc. Since the Middle Pleistocene, eruption of ~ 350 km3 of basalt through rhyolite has produced a 30 km, arc front chain of nested calderas and overlapping stratovolcanoes. ELVC has experienced as many as five major caldera-forming eruptions, the most recent, a
Authors
M. Mangan, T. Miller, C. Waythomas, F. Trusdell, A. Calvert, P. Layer
Photometric changes on Saturn's Titan: Evidence for active cryovolcanism
We report infrared spectrophotometric variability on the surface of Saturn's moon Titan detected in images returned by the Visual and Infrared Mapping Spectrometer (VIMS) onboard the Cassini Saturn Orbiter. The changes were observed at 7°S, 138°W and occurred between October 27, 2005 and January 15, 2006. After that date the surface was unchanged until the most recent observation, March 18, 2006.
Authors
Robert M. Nelson, Lucas W. Kamp, Rosaly M.C. Lopes, Dennis L. Matson, Randolph L. Kirk, Bruce W. Hapke, Stephen D. Wall, Mark D. Boryta, Frank E. Leader, William D. Smythe, Karl L. Mitchell, Kevin H. Baines, Ralf Jaumann, Christophe Sotin, Roger N. Clark, Dale P. Cruikshank, Pierre Drossart, Jonathan I. Lunine, Michel Combes, Giancarlo Bellucci, Jean-Pierre Bibring, Fabrizio Capaccioni, Pricilla Cerroni, Angioletta Coradini, Vittorio Formisano, Gianrico Filacchione, Yves Langevin, Thomas B. McCord, Vito Mennella, Philip D. Nicholson, Bruno Sicardy, Patrick G.J. Irwin, John C. Pearl
El Chichón's "surprise" eruption in 1982: lessons for reducing volcano risk
During one week (28 March–4 April 1982), three powerful explosive eruptions (VEI 5) of El Chichón Volcano caused the worst volcanic disaster in Mexico's recorded history. Pyroclastic flows and surges obliterated nine villages, killing about 2,000 people, and ashfalls downwind posed socio–economic hardships for many thousands of inhabitants of the States of Chiapas and Tabasco. The unexpected and v
Authors
R. I. Tilling
Mapping products of Titan's surface
Remote sensing instruments aboard the Cassini spacecraft have been observed the surface of Titan globally in the infrared and radar wavelength ranges as well as locally by the Huygens instruments revealing a wealth of new morphological features indicating a geologically active surface. We present a summary of mapping products of Titan's surface derived from data of the remote sensing instruments o
Authors
Katrin Stephan, Ralf Jaumann, Erich Karkoschka, Jason W. Barnes, Martin G. Tomasko, Elizabeth P. Turtle, Lucille Le Corre, Mirjam Langhans, Stephane Le Mouelic, Ralf D. Lorenz, Jason Perry
Ice and water on Newberry Volcano, central Oregon
Newberry Volcano in central Oregon is dry over much of its vast area, except for the lakes in the caldera and the single creek that drains them. Despite the lack of obvious glacial striations and well-formed glacial moraines, evidence indicates that Newberry was glaciated. Meter-sized foreign blocks, commonly with smoothed shapes, are found on cinder cones as far as 7 km from the caldera rim. Thes
Authors
Julie M. Donnelly-Nolan, Robert A. Jensen
Hydrodynamic modeling of tsunamis from the Currituck landslide
Tsunami generation from the Currituck landslide offshore North Carolina and propagation of waves toward the U.S. coastline are modeled based on recent geotechnical analysis of slide movement. A long and intermediate wave modeling package (COULWAVE) based on the non-linear Boussinesq equations are used to simulate the tsunami. This model includes procedures to incorporate bottom friction, wave brea
Authors
E.L. Geist, P.J. Lynett, J.D. Chaytor
Uplift and magma intrusion at Long Valley caldera from InSAR and gravity measurements
The Long Valley caldera (California) formed ~760,000 yr ago following the massive eruption of the Bishop Tuff. Postcaldera volcanism in the Long Valley volcanic field includes lava domes as young as 650 yr. The recent geological unrest is characterized by uplift of the resurgent dome in the central section of the caldera (75 cm in the past 33 yr) and earthquake activity followed by periods of rela
Authors
Pietro Tizzani, Maurizio Battaglia, Giovanni Zeni, Simone Atzori, Paolo Berardino, Riccardo Lanari
Kulanaokuaiki Tephra (ca, A.D. 400-1000): Newly recognized evidence for highly explosive eruptions at Kilauea Volcano, Hawai'i
Kīlauea may be one of the world's most intensively monitored volcanoes, but its eruptive history over the past several thousand years remains rather poorly known. Our study has revealed the vestiges of thin basaltic tephra deposits, overlooked by previous workers, that originally blanketed wide, near-summit areas and extended more than 17 km to the south coast of Hawai‘i. These deposits, correlati
Authors
R.S. Fiske, T.R. Rose, D. A. Swanson, D. E. Champion, J. P. McGeehin