Publications
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CO2 jets formed by sublimation beneath translucent slab ice in Mars' seasonal south polar ice cap CO2 jets formed by sublimation beneath translucent slab ice in Mars' seasonal south polar ice cap
The martian polar caps are among the most dynamic regions on Mars, growing substantially in winter as a significant fraction of the atmosphere freezes out in the form of CO2 ice. Unusual dark spots, fans and blotches form as the south-polar seasonal CO2 ice cap retreats during spring and summer. Small radial channel networks are often associated with the location of spots once the ice...
Authors
Hugh H. Kieffer, Phillip R. Christensen, Timothy N. Titus
A plastic flow model for the Acquara - Vadoncello landslide in Senerchia, Southern Italy A plastic flow model for the Acquara - Vadoncello landslide in Senerchia, Southern Italy
A previously developed model for stress and velocity fields in two-dimensional Coulomb plastic materials under self-weight and pore pressure predicts that long, shallow landslides develop slip surfaces that manifest themselves as normal faults and normal fault scarps at the surface in areas of extending flow and as thrust faults and thrust fault scarps at the surface in areas of...
Authors
W. Savage, J. Wasowski
Abrupt transitions during sustained explosive eruptions: Examples from the 1912 eruption of Novarupta, Alaska Abrupt transitions during sustained explosive eruptions: Examples from the 1912 eruption of Novarupta, Alaska
Plinian/ignimbrite activity stopped briefly and abruptly 16 and 45 h after commencement of the 1912 Novarupta eruption defining three episodes of explosive volcanism before finally giving way after 60 h to effusion of lava domes. We focus here on the processes leading to the termination of the second and third of these three episodes. Early erupted pumice from both episodes show a very...
Authors
N.K. Adams, Bruce F. Houghton, W. Hildreth
Eruptive history and geochronology of Mount Mazama and the Crater Lake region, Oregon Eruptive history and geochronology of Mount Mazama and the Crater Lake region, Oregon
Geologic mapping, K-Ar, and 40Ar/39Ar age determinations, supplemented by paleomagnetic measurements and geochemical data, are used to quantify the Quaternary volcanic history of the Crater Lake region in order to define processes and conditions that led to voluminous explosive eruptions. The Cascade arc volcano known as Mount Mazama collapsed during its climactic eruption of ∼50 km3 of...
Authors
Charles R. Bacon, Marvin A. Lanphere
Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component Isotope geochemistry of early Kilauea magmas from the submarine Hilina bench: The nature of the Hilina mantle component
Submarine lavas recovered from the Hilina bench region, offshore Kilauea, Hawaii Island provide information on ancient Kilauea volcano and the geochemical components of the Hawaiian hotspot. Alkalic lavas, including nephelinite, basanite, hawaiite, and alkali basalt, dominate the earliest stage of Kilauea magmatism. Transitional basalt pillow lavas are an intermediate phase, preceding...
Authors
Jun-Ichi Kimura, Thomas W. Sisson, Natsuko Nakano, Michelle L. Coombs, Peter W. Lipman
Inflation model of Uzon caldera, Kamchatka, constrained by satellite radar interferometry observations Inflation model of Uzon caldera, Kamchatka, constrained by satellite radar interferometry observations
We analyzed RADARSAT-1 synthetic aperture radar (SAR) data to compute interferometric SAR (InSAR) images of surface deformation at Uzon caldera, Kamchatka, Russia. From 2000 to 2003 approximately 0.15 m of inflation occurred at Uzon caldera, extending beneath adjacent Kikhpinych volcano. This contrasts with InSAR data showing no significant deformation during either the 1999 to 2000, or...
Authors
Paul Lundgren, Zhong Lu
Two years at Meridiani Planum: Results from the Opportunity Rover Two years at Meridiani Planum: Results from the Opportunity Rover
The Mars Exploration Rover Opportunity has spent more than 2 years exploring Meridiani Planum, traveling ∼8 kilometers and detecting features that reveal ancient environmental conditions. These include well-developed festoon (trough) cross-lamination formed in flowing liquid water, strata with smaller and more abundant hematite-rich concretions than those seen previously, possible relict...
Authors
S. W. Squyres, A.H. Knoll, R. E. Arvidson, B. C. Clark, J.P. Grotzinger, B.L. Jolliff, S. M. McLennan, N. Tosca, J.F. Bell, W. M. Calvin, W. H. Farrand, T.D. Glotch, M.P. Golombek, Kenneth E. Herkenhoff, J. R. Johnson, G. Klingelhofer, H.Y. McSween, A. S. Yen
Titan Radar Mapper observations from Cassini's T3 fly-by Titan Radar Mapper observations from Cassini's T3 fly-by
Cassini's Titan Radar Mapper imaged the surface of Saturn's moon Titan on its February 2005 fly-by (denoted T3), collecting high-resolution synthetic-aperture radar and larger-scale radiometry and scatterometry data. These data provide the first definitive identification of impact craters on the surface of Titan, networks of fluvial channels and surficial dark streaks that may be...
Authors
C. Elachi, S. Wall, M. Janssen, E. Stofan, R. Lopes, Randolph L. Kirk, R. Lorenz, J. Lunine, F. Paganelli, Laurence A. Soderblom, C. Wood, L. Wye, H. Zebker, Y. Anderson, S. Ostro, M. Allison, R. Boehmer, P. Callahan, P. Encrenaz, E. Flamini, G. Francescetti, Y. Gim, G. Hamilton, S. Hensley, W. Johnson, K. Kelleher, D. Muhleman, G. Picardi, F. Posa, L. Roth, R. Seu, S. Shaffer, B. Stiles, S. Vetrella, R. West
Comparison of COSPEC and two miniature ultraviolet spectrometer systems for SO2 measurements using scattered sunlight Comparison of COSPEC and two miniature ultraviolet spectrometer systems for SO2 measurements using scattered sunlight
The correlation spectrometer (COSPEC), the principal tool for remote measurements of volcanic SO2, is rapidly being replaced by low-cost, miniature, ultraviolet (UV) spectrometers. We compared two of these new systems with a COSPEC by measuring SO2 column amounts at Kīlauea Volcano, Hawaii. The two systems, one calibrated using in-situ SO2 cells, and the other using a calibrated...
Authors
Tamar Elias, A. Jeff Sutton, Clive Oppenheimer, Keith A. Horton, Harold Garbeil, Vitchko Tsanev, Andrew J.S. McGonigle, Glyn Williams-Jones
The heartbeat of the volcano: The discovery of episodic activity at Prometheus on Io The heartbeat of the volcano: The discovery of episodic activity at Prometheus on Io
The temporal signature of thermal emission from a volcano is a valuable clue to the processes taking place both at and beneath the surface. The Galileo Near Infrared Mapping Spectrometer (NIMS) observed the volcano Prometheus, on the jovian moon Io, on multiple occasions between 1996 and 2002. The 5 micron (μm) brightness of this volcano shows considerable variation from orbit to orbit...
Authors
Ashley G. Davies, Lionel Wilson, Dennis Matson, Giovanni Leone, Laszlo P. Keszthelyi, Windy L. Jaeger
Calculated volumes of individual shield volcanoes at the young end of the Hawaiian Ridge Calculated volumes of individual shield volcanoes at the young end of the Hawaiian Ridge
High-resolution multibeam bathymetry and a digital elevation model of the Hawaiian Islands are used to calculate the volumes of individual shield volcanoes and island complexes (Niihau, Kauai, Oahu, the Maui Nui complex, and Hawaii), taking into account subsidence of the Pacific plate under the load of the Hawaiian Ridge. Our calculated volume for the Island of Hawaii and its submarine...
Authors
Joel E. Robinson, Barry W. Eakins
Submarine landslides in the Santa Barbara Channel as potential tsunami sources Submarine landslides in the Santa Barbara Channel as potential tsunami sources
Recent investigations using the Monterey Bay Aquarium Research Institutes (MBARI) Remotely Operated Vehicles (ROVs) "Ventana" and "Tiburon" and interpretation of MBARI's EM 300 30 kHz multibeam bathymetric data show that the northern flank of the Santa Barbara Basin has experienced massive slope failures. Of particular concern is the large (130 km2) Goleta landslide complex located off...
Authors
H. Gary Greene, L.Y. Murai, P. Watts, N.A. Maher, M. A. Fisher, C.E. Paull, P. Eichhubl