Publications
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A catastrophic meltwater flood event and the formation of the Hudson Shelf Valley
The Hudson Shelf Valley (HSV) is the largest physiographic feature on the U.S. mid-Atlantic continental shelf. The 150-km long valley is the submerged extension of the ancestral Hudson River Valley that connects to the Hudson Canyon. Unlike other incised valleys on the mid-Atlantic shelf, it has not been infilled with sediment during the Holocene. Analyses of multibeam bathymetry, acoustic backsca
Authors
E. Robert Thieler, Bradford Butman, William C. Schwab, Mead A. Allison, Neal W. Driscoll, John P. Donnelly, Elazar Uchupi
The colonial ascidian Didemnum sp. A: current distribution, basic biology and potential threat to marine communities of the northeast and west coasts of North America
Didemnum sp. A is a colonial ascidian with rapidly expanding populations on the east and west coasts of North America. The origin of Didemum sp. A is unknown. Populations were first observed on the northeast coast of the U.S. in the late 1980s and on the west coast during the 1990s. It is currently undergoing a massive population explosion and is now a dominant member of many subtidal communities
Authors
S.G. Bullard, G. Lambert, M.R. Carman, J. Byrnes, R.B. Whitlatch, G. Ruiz, R. J. Miller, L. Harris, P. C. Valentine, J.S. Collie, J. Pederson, D.C. McNaught, A.N. Cohen, R. G. Asch, J. Dijkstra, K. Heinonen
New K-Ar ages for calculating end-of-shield extrusion rates at West Maui volcano, Hawaiian island chain
Thirty-seven new K–Ar ages from West Maui volcano, Hawai‘i, are used to define the waning stages of shield growth and a brief episode of postshield volcanism. All but two samples from shield-stage strata have reversed polarity magnetization, so conceivably the exposed shield is not much older than the Olduvai Normal-Polarity subchron, or about 1.8 Ma. The oldest ages obtained are in the range 1.9–
Authors
David R. Sherrod, T. Murai, Takahiro Tagami
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 cyclothem
Authors
G.C. Ohlmacher
Restoring coastal wetlands that were ditched for mosquito control: a preliminary assessment of hydro-leveling as a restoration technique
The wetlands surrounding Tampa Bay, Florida were extensively ditched for mosquito control in the 1950s. Spoil from ditch construction was placed adjacent to the wetlands ditches creating mound-like features (spoil-mounds). These mounds represent a loss of 14% of the wetland area in Tampa Bay. Spoil mounds interfere with tidal flow and are locations for non-native plants to colonize (e.g., Schinus
Authors
Thomas J. Smith, Ginger Tiling, Pamela S. Leasure
Three-dimensional structure of fluid conduits sustaining an active deep marine cold seep
Cold seeps in deep marine settings emit fluids to the overlying ocean and are often associated with such seafloor flux indicators as chemosynthetic biota, pockmarks, and authigenic carbonate rocks. Despite evidence for spatiotemporal variability in the rate, locus, and composition of cold seep fluid emissions, the shallow subseafloor plumbing systems have never been clearly imaged in three dimensi
Authors
M.J. Hornbach, C. Ruppel, C.L. Van Dover
Compositional zoning of the Bishop Tuff
Compositional data for >400 pumice clasts, organized according to eruptive sequence, crystal content, and texture, provide new perspectives on eruption and pre-eruptive evolution of the >600 km3 of zoned rhyolitic magma ejected as the Bishop Tuff during formation of Long Valley caldera. Proportions and compositions of different pumice types are given for each ignimbrite package and for the interca
Authors
W. Hildreth, C. J. N. Wilson
Simultaneous determination of thermal conductivity, thermal diffusivity and specific heat in sI methane hydrate
Thermal conductivity, thermal diffusivity and specific heat of sI methane hydrate were measured as functions of temperature and pressure using a needle probe technique. The temperature dependence was measured between −20°C and 17°C at 31.5 MPa. The pressure dependence was measured between 31.5 and 102 MPa at 14.4°C. Only weak temperature and pressure dependencies were observed. Methane hydrate the
Authors
W.F. Waite, L.A. Stern, S. H. Kirby, W.J. Winters, D.H. Mason
Mars reconnaissance orbiter's high resolution imaging science experiment (HiRISE)
The HiRISE camera features a 0.5 m diameter primary mirror, 12 m effective focal length, and a focal plane system that can acquire images containing up to 28 Gb (gigabits) of data in as little as 6 seconds. HiRISE will provide detailed images (0.25 to 1.3 m/pixel) covering ∼1% of the Martian surface during the 2‐year Primary Science Phase (PSP) beginning November 2006. Most images will include col
Authors
Alfred S. McEwen, Eric M. Eliason, James W. Bergstrom, Nathan T. Bridges, Candice J. Hansen, W. Alan Delamere, John A. Grant, Virginia C. Gulick, Kenneth E. Herkenhoff, Laszlo P. Keszthelyi, Randolph L. Kirk, Michael T. Mellon, Steven W. Squyres, Nicolas Thomas, Catherine M. Weitz
Regression models for estimating coseismic landslide displacement
Newmark's sliding-block model is widely used to estimate coseismic slope performance. Early efforts to develop simple regression models to estimate Newmark displacement were based on analysis of the small number of strong-motion records then available. The current availability of a much larger set of strong-motion records dictates that these regression equations be updated. Regression equations we
Authors
R. W. Jibson
A simple model for the spatially-variable coastal response to hurricanes
The vulnerability of a beach to extreme coastal change during a hurricane can be estimated by comparing the relative elevations of storm-induced water levels to those of the dune or berm. A simple model that defines the coastal response based on these elevations was used to hindcast the potential impact regime along a 50-km stretch of the North Carolina coast to the landfalls of Hurricane Bonnie o
Authors
H.F. Stockdon, A. H. Sallenger, R.A. Holman, P.A. Howd
Mangrove removal in the belize cays: effects on mangrove-associated fish assemblages in the intertidal and subtidal
We investigated the effects of mangrove cutting on fish assemblages in Twin Cays, Belize, in two habitat types. We conducted visual censuses at two sites in adjoining undisturbed/disturbed (30%–70% of shoreline fringe removed) sub-tidal fringing Rhizophora mangle Linnaeus, 1753. Observers recorded significantly more species and individuals in undisturbed sites, especially among smaller, schooling
Authors
D.S. Taylor, E.A. Reyier, W.P. Davis, C.C. McIvor