Publications
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Predicting and validating the motion of an ash cloud during the 2006 eruption of Mount Augustine volcano Predicting and validating the motion of an ash cloud during the 2006 eruption of Mount Augustine volcano
On 11 January 2006, Mount Augustine volcano in southern Alaska began erupting after 20- year repose. The Anchorage Forecast Office of the National Weather Service (NWS) issued an advisory on 28 January for Kodiak City. On 31 January, Alaska Airlines cancelled all flights to and from Anchorage after multiple advisories from the NWS for Anchorage and the surrounding region. The Alaska...
Authors
Richard L. Collins, Javier Fochesatto, Kenneth Sassen, Peter W. Webley, David E. Atkinson, Kenneson G. Dean, Catherine F. Cahill, Kohei Mizutani
Pāhoehoe flow cooling, discharge, and coverage rates from thermal image chronometry Pāhoehoe flow cooling, discharge, and coverage rates from thermal image chronometry
Theoretically- and empirically-derived cooling rates for active pāhoehoe lava flows show that surface cooling is controlled by conductive heat loss through a crust that is thickening with the square root of time. The model is based on a linear relationship that links log(time) with surface cooling. This predictable cooling behavior can be used assess the age of recently emplaced sheet...
Authors
Jonathan Dehn, Christopher M. Hamilton, A. J. L. Harris, Richard A. Herd, M.R. James, Luigi Lodato, Andrea Steffke
Seafloor mapping and benthic habitat GIS for southern California, volume III Seafloor mapping and benthic habitat GIS for southern California, volume III
From August 8-27, 2005, more than 75 km of the continental shelf (Fig. 1) in water depths of 20-70m southeast of Santa Barbara, were surveyed during the USGS cruise S-1-05-SC (http://walrus.wr.usgs.gov/infobank/s/s105sc/html/s-1-05-sc.meta.html). Both Interferometric sonar and 14 hours of both vertical and oblique georeferenced submarine digital video were collected to (1) obtain...
Authors
Guy R. Cochrane, Nadine E. Golden, Pete Dartnell, Donna M. Schroeder, David P. Finlayson
A Compilation of Gas Emission-Rate Data from Volcanoes of Cook Inlet (Spurr, Crater Peak, Redoubt, Iliamna, and Augustine) and Alaska Peninsula (Douglas, Fourpeaked, Griggs, Mageik, Martin, Peulik, Ukinrek Maars, and Veniaminof), Alaska, from 1995-2006 A Compilation of Gas Emission-Rate Data from Volcanoes of Cook Inlet (Spurr, Crater Peak, Redoubt, Iliamna, and Augustine) and Alaska Peninsula (Douglas, Fourpeaked, Griggs, Mageik, Martin, Peulik, Ukinrek Maars, and Veniaminof), Alaska, from 1995-2006
INTRODUCTION This report presents gas emission rates from data collected during numerous airborne plume-measurement flights at Alaskan volcanoes since 1995. These flights began in about 1990 as means to establish baseline values of volcanic gas emissions during periods of quiescence and to identify anomalous levels of degassing that might signal the beginning of unrest. The primary goal...
Authors
Michael P. Doukas, Kenneth A. McGee
Side-scan sonar imaging of the Colorado River, Grand Canyon Side-scan sonar imaging of the Colorado River, Grand Canyon
This paper presents data collection methods and side-scan sonar data collected along the Colorado River in Grand Canyon in August and September of 2000. The purpose of the data collection effort was to image the distribution of sand between Glen Canyon Dam and river mile 87.4 before and after the 31,600 cfs flow of September 6-8. The side-scan sonar imaging focused on pools between...
Authors
Roberto Anima, Florence L. Wong, David Hogg, Peter Galanis
Massive edifice failure at Aleutian arc volcanoes Massive edifice failure at Aleutian arc volcanoes
Along the 450-km-long stretch of the Aleutian volcanic arc from Great Sitkin to Kiska Islands, edifice failure and submarine debris-avalanche deposition have occurred at seven of ten Quaternary volcanic centers. Reconnaissance geologic studies have identified subaerial evidence for large-scale prehistoric collapse events at five of the centers (Great Sitkin, Kanaga, Tanaga, Gareloi, and...
Authors
Michelle L. Coombs, S.M. White, D.W. Scholl
THEMIS observes possible cave skylights on Mars THEMIS observes possible cave skylights on Mars
Seven possible skylight entrances into Martian caves were observed on and around the flanks of Arsia Mons by the Mars Odyssey Thermal Emission Imaging System (THEMIS). Distinct from impact craters, collapse pits or any other surface feature on Mars, these candidates appear to be deep dark holes at visible wavelengths while infrared observations show their thermal behaviors to be...
Authors
Glen Cushing, Timothy N. Titus, J. Judson Wynne, P. R. Christensen
Analysis of multiple enteric viral targets as sewage markers in coral reefs Analysis of multiple enteric viral targets as sewage markers in coral reefs
Water and coral mucus samples were collected from throughout the Florida Keys National Marine Sanctuary and the Dry Tortugas for three years and were analyzed for human enteric viruses (enteroviruses, noroviruses, hepatitis A virus and adenoviruses) as conservative markers of human sewage using molecular methods. Of the 100 coral and water samples collected, 40 contained genetic material...
Authors
Erin K. Lipp, J. Carrie Futch, Dale W. Griffin
Role of aquifer heterogeneity in fresh groundwater discharge and seawater recycling: An example from the Carmel coast, Israel Role of aquifer heterogeneity in fresh groundwater discharge and seawater recycling: An example from the Carmel coast, Israel
A case study is shown in which the pattern of submarine groundwater discharge and of seawater recycling is controlled by local hydrogeological variability. The coastal aquifer in Dor Bay is composed of two units: a partly confined calcaranitic sandstone (Kurkar) and an overlying loose sand. Groundwater in the Kurkar has elevated activities of 222Rn (∼390 dpm/L) and relatively low 224Ra...
Authors
Y. Weinstein, W. C. Burnett, P.W. Swarzenski, Y. Shalem, Y. Yechieli, B. Herut
Generation and propagation of nonlinear internal waves in Massachusetts Bay Generation and propagation of nonlinear internal waves in Massachusetts Bay
During the summer, nonlinear internal waves (NLIWs) are commonly observed propagating in Massachusetts Bay. The topography of the area is unique in the sense that the generation area (over Stellwagen Bank) is only 25 km away from the shoaling area, and thus it represents an excellent natural laboratory to study the life cycle of NLIWs. To assist in the interpretation of the data...
Authors
A. Scotti, R.C. Beardsley, B. Butman
Why the sacramento delta area differs from other parts of the great valley: numerical modeling of thermal structure and thermal subsidence of forearc basins Why the sacramento delta area differs from other parts of the great valley: numerical modeling of thermal structure and thermal subsidence of forearc basins
Data on present-day heat flow, subsidence history, and paleotemperature for the Sacramento Delta region, California, have been employed to constrain a numerical model of tectonic subsidence and thermal evolution of forearc basins. The model assumes an oceanic basement with an initial thermal profile dependent on its age subjected to refrigeration caused by a subducting slab. Subsidence...
Authors
V.O. Mikhailov, T. Parsons, R.W. Simpson, E.P. Timoshkina, C. Williams
Pre-eruption recharge of the Bishop magma system Pre-eruption recharge of the Bishop magma system
The 650 km3 rhyolitic Bishop Tuff (eastern California, USA), which is stratigraphically zoned with respect to temperatures of mineral equilibration, reflects a corresponding thermal gradient in the source magma chamber. Consistent with previous work, application of the new TitaniQ (Ti-in-quartz) thermometer to quartz phenocryst rims documents an ∼100 °C temperature increase with chamber...
Authors
D.A. Wark, W. Hildreth, F.S. Spear, D.J. Cherniak, E.B. Watson