Publications
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Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars
During its exploration of the Columbia Hills, the Mars Exploration Rover "Spirit" encountered several similar samples that are distinctly different from Martian meteorites and known Gusev crater soils, rocks, and sediments. Occurring in a variety of contexts and locations, these "Independence class" samples are rough-textured, iron-poor (equivalent FeO ??? 4 wt%), have high Al/Si ratios, and often
Authors
B. C. Clark, R. E. Arvidson, Ralf Gellert, R.V. Morris, D. W. Ming, L. Richter, S. W. Ruff, J.R. Michalski, W. H. Farrand, A. S. Yen, Kenneth E. Herkenhoff, R. Li, S. W. Squyres, C. Schroder, G. Klingelhofer, J.F. Bell
Close temporal correspondence between geomagnetic anomalies and earthquakes during the 2002-2003 eruption of Etna volcano
The early stages of the 2002-2003 lateral eruption at Mount Etna were accompanied by slow changes (over some hours) and some rapid step offsets in the local magnetic field. At five monitoring locations, the total magnetic field intensity has been measured using continuously operating Overhauser magnetometers at a sampling rate of 10 s. The very unique aspect of these observations is the close temp
Authors
G. Currenti, Negro C. Del, M. Johnston, Y. Sasai
Paleoenvironmental assessment of recent environmental changes in Florida Bay, USA: a biomarker based study
The extractable lipid compositions in four Florida Bay cores were determined in order to understand environmental changes over the last 160 years. The most significant environmental change was recorded by oscillations in the amplitude and frequency of biomarkers during the 20th century. Two seagrass molecular proxies (Paq and the C25/C27n-alkan-2-one ratio) reached a maximum post 1900, suggesting
Authors
Y. Xu, C. W. Holmes, R. Jaffe
Suspended-sediment rating curve response to urbanization and wildfire, Santa Ana River, California
[1] River suspended-sediment concentrations provide insights to the erosion and transport of materials from a landscape, and changes in concentrations with time may result from landscape processes or human disturbance. Here we show that suspended-sediment concentrations in the Santa Ana River, California, decreased 20-fold with respect to discharge during a 34-year period (1968−2001). These decrea
Authors
J.A. Warrick, D. M. Rubin
Seismic-reflection images of the crust beneath the 2001 M = 7.7 Kutch (Bhuj) epicentral region, western India
Three short (∼35 km) seismic-reflection profiles are presented from the region of the 2001 Mw = 7.7 Bhuj (western India) earthquake. These profiles image a 35–45-km-thick crust with strong, near-horizontal reflections at all depths. The thickness of the crust increases by 10 km over a distance of ∼50 km from the northern margin of the Gulf of Kutch to the earthquake epicenter. Aftershocks of the B
Authors
Dipankar Sarkar, K. Sain, P.R. Reddy, Rufus D. Catchings, Walter D. Mooney
Electrical activity during the 2006 Mount St. Augustine volcanic eruptions
By using a combination of radio frequency time-of-arrival and interferometer measurements, we observed a sequence of lightning and electrical activity during one of Mount St. Augustine's eruptions. The observations indicate that the electrical activity had two modes or phases. First, there was an explosive phase in which the ejecta from the explosion appeared to be highly charged upon exiting the
Authors
Ronald J. Thomas, Paul R. Krehbiel, William Rison, H. E. Edens, G. D. Aulich, S.R. McNutt, Guy Tytgat, E. Clark
Discussion of The mantle plume debate in undergraduate geoscience education: Overview, history, and recommendations
No abstract available.
Authors
Robert I. Tilling
Volcanic ash plume identification using polarization lidar: Augustine eruption, Alaska
During mid January to early February 2006, a series of explosive eruptions occurred at the Augustine volcanic island off the southern coast of Alaska. By early February a plume of volcanic ash was transported northward into the interior of Alaska. Satellite imagery and Puff volcanic ash transport model predictions confirm that the aerosol plume passed over a polarization lidar (0.694 mm wavelength
Authors
Kenneth Sassen, Jiang Zhu, Peter W. Webley, K. Dean, Patrick Cobb
The question of recharge to the deep thermal reservoir underlying the geysers and hot springs of Yellowstone National Park: Chapter H in Integrated geoscience studies in Integrated geoscience studies in the Greater Yellowstone Area—Volcanic, tectonic,
The extraordinary number, size, and unspoiled beauty of the geysers and hot springs of Yellowstone National Park (the Park) make them a national treasure. The hydrology of these special features and their relation to cold waters of the Yellowstone area are poorly known. In the absence of deep drill holes, such information is available only indirectly from isotope studies. The δD-δ18O values of pre
Authors
Robert O. Rye, Alfred Hemingway Truesdell
Modeling the dynamic response of a crater glacier to lava-dome emplacement: Mount St Helens, Washington, USA
The debris-rich glacier that grew in the crater of Mount St Helens after the volcano's cataclysmic 1980 eruption was split in two by a new lava dome in 2004. For nearly six months, the eastern part of the glacier was squeezed against the crater wall as the lava dome expanded. Glacier thickness nearly doubled locally and surface speed increased substantially. As squeezing slowed and then stopped,
Authors
Stephen F. Price, Joseph S. Walder
Crisis GIS--Preparing for and responding to volcanic eruptions in the United States
No abstract available.
Authors
D.W. Ramsey, J.E. Robinson, S. P. Schilling, J.R. Schaefer, Frank A. Trusdell
Crustal deformation of the Yellowstone-Snake River Plain volcano-tectonic system-Campaign and continuous GPS observations, 1987-2004
The Yellowstone-Snake River Plain tectonomagmatic province resulted from Late Tertiary volcanism in western North America, producing three large, caldera-forming eruptions at the Yellowstone Plateau in the last 2 Myr. To understand the kinematics and geodynamics of this volcanic system, the University of Utah conducted seven GPS campaigns at 140 sites between 1987 and 2003 and installed a networ
Authors
C.M. Puskas, R. B. Smith, Charles M. Meertens, W. L. Chang