Publications
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Progress in the development of shallow-water mapping systems Progress in the development of shallow-water mapping systems
The USGS (US Geological Survey) Coastal and Marine Geology has deployed an advance autonomous shallow-draft robotic vehicle, Iris, for shallow-water mapping in Apalachicola Bay, Florida. The vehicle incorporates a side scan sonar system, seismic-reflection profiler, single-beam echosounder, and global positioning system (GPS) navigation. It is equipped with an onboard microprocessor...
Authors
E. Bergeron, C.R. Worley, T. O'Brien
Plan curvature and landslide probability in regions dominated by earth flows and earth slides Plan curvature and landslide probability in regions dominated by earth flows and earth slides
Damaging landslides in the Appalachian Plateau and scattered regions within the Midcontinent of North America highlight the need for landslide-hazard mapping and a better understanding of the geomorphic development of landslide terrains. The Plateau and Midcontinent have the necessary ingredients for landslides including sufficient relief, steep slope gradients, Pennsylvanian and Permian
Authors
G.C. Ohlmacher
Mechanical properties of sand, silt, and clay containing tetrahydrofuran hydrate Mechanical properties of sand, silt, and clay containing tetrahydrofuran hydrate
The mechanical behavior of hydrate-bearing sediments subjected to large strains has relevance for the stability of the seafloor and submarine slopes, drilling and coring operations, and the analysis of certain small-strain properties of these sediments (for example, seismic velocities). This study reports on the results of comprehensive axial compression triaxial tests conducted at up to...
Authors
T.S. Yun, J.C. Santamarina, C. Ruppel
Barite-forming environments along a rifted continental margin, Southern California Borderland Barite-forming environments along a rifted continental margin, Southern California Borderland
The Southern California Continental Borderland (SCCB) is part of the broad San Andreas transform-fault plate boundary that consists of a series of fault-bounded, petroleum-generating basins. The SCCB has high heat flow and geothermal gradients produced by thinned continental crust and Neogene volcanism. Barite deposits in the SCCB occur along faults. Barite samples from two sea-cliff...
Authors
James R. Hein, Robert A. Zierenberg, J. Barry Maynard, Mark D. Hannington
Meter-scale morphology of the north polar region of mars Meter-scale morphology of the north polar region of mars
Mars' north pole is covered by a dome of layered ice deposits. Detailed (∼30 centimeters per pixel) images of this region were obtained with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter (MRO). Planum Boreum basal unit scarps reveal cross-bedding and show evidence for recent mass wasting, flow, and debris accumulation. The north polar layers...
Authors
Kenneth E. Herkenhoff, S. Byrne, P.S. Russell, K.E. Fishbaugh, A. S. McEwen
Ecological observations on the colonial ascidian Didemnum sp. in a New England tide pool habitat Ecological observations on the colonial ascidian Didemnum sp. in a New England tide pool habitat
The colonial ascidian Didemnum sp. has colonized northwestern Atlantic coastal habitats from southern Long Island, New York, to Eastport, Maine. It is also present in offshore habitats of the Georges Bank fishing grounds. It threatens to alter fisheries habitats and shellfish aquacultures. Observations in a tide pool at Sandwich, MA from December 2003 to February 2006 show that Didemnum...
Authors
P. C. Valentine, M.R. Carman, D.S. Blackwood, E.J. Heffron
An assessment of ichthyofaunal assemblages within the mangal of the Belize offshore cays An assessment of ichthyofaunal assemblages within the mangal of the Belize offshore cays
We assessed ichthyofaunal diversity within offshore mangrove cays in Belize during three, 2-wk surveys (2003, 2004, 2005). Nine sampling gears were deployed in pre-defined micro-habitats: fringe, transition, dwarf red mangrove, internal creeks, ponds, and sinkholes. Water quality data (temperature, salinity, DO) were taken during most collections. A total of 2586 gear sets was completed...
Authors
D.S. Taylor, E.A. Reyier, C.C. McIvor, W.P. Davis
Spatial and temporal geochemical trends in the hydrothermal system of Yellowstone National Park: Inferences from river solute fluxes Spatial and temporal geochemical trends in the hydrothermal system of Yellowstone National Park: Inferences from river solute fluxes
We present and analyze a chemical dataset that includes the concentrations and fluxes of HCO3−, SO42−, Cl−, and F− in the major rivers draining Yellowstone National Park (YNP) for the 2002–2004 water years (1 October 2001 – 30 September 2004). The total (molar) flux in all rivers decreases in the following order, HCO3− > Cl− > SO42− > F−, but each river is characterized by a distinct...
Authors
Shaul Hurwitz, Jacob B. Lowenstern, Henry Heasler
Electrical activity during the 2006 Mount St. Augustine volcanic eruptions 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...
Authors
Ronald J. Thomas, Paul R. Krehbiel, William Rison, H. E. Edens, G. D. Aulich, S.R. McNutt, Guy Tytgat, E. Clark
Crisis GIS--Preparing for and responding to volcanic eruptions in the United States 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
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