Publications
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Landslides triggered by the Northridge earthquake
No abstract available.
Authors
R. W. Jibson, E. L. Harp, D. K. Keefer, R. C. Wilson
Historical shoreline mapping (I): improving techniques and reducing positioning errors
A critical need exists among coastal researchers and policy-makers for a precise method to obtain shoreline positions from historical maps and aerial photographs. A number of methods that vary widely in approach and accuracy have been developed to meet this need. None of the existing methods, however, address the entire range of cartographic and photogrammetric techniques required for accurate coa
Authors
E. Robert Thieler, William W. Danforth
New recording package for VACM provides sensor flexibility
For the past three decades, the VACM has been a standard for ocean current measurements. A VACM is a true vector-averaging instrument that computes north and east current vectors and averages temperature continuously over a specified interval. It keeps a running total of rotor counts, and records one-shot samples of compass, vane position and time. Adding peripheral sensors to the data stream was
Authors
William J. Strahle, S. E. Worrilow, S. E. Fucile, Marinna A. Martini
Antifouling leaching technique for optical lenses
The effectiveness of optical lenses deployed in water less than 100 m deep is significantly reduced by biofouling caused by the settlement of macrofauna, such as barnacles, hydroids, and tunicates. However, machineable porous plastic rings can be used to dispense antifoulant into the water in front of the lens to retard macrofaunal growth without obstructing the light path. Unlike coatings which c
Authors
William J. Strahle, C. L. Perez, Marinna A. Martini
Historical shoreline mapping (II): Application of the Digital Shoreline Mapping and Analysis Systems (DSMS/DSAS) to shoreline change mapping in Puerto Rico
A new, state-of-the-art method for mapping historical shorelines from maps and aerial photographs, the Digital Shoreline Mapping System (DSMS), has been developed. The DSMS is a freely available, public domain software package that meets the cartographic and photogrammetric requirements of precise coastal mapping, and provides a means to quantify and analyze different sources of error in the mappi
Authors
E. Robert Thieler, William W. Danforth
Submarine canyon initiation by downslope-eroding sediment flows: Evidence in late Cenozoic strata on the New Jersey continental slope
Multibeam bathymetry and seismic reflection profiles of the New Jersey continental slope reveal a series of abandoned and now-buried submarine canyons that have apparently influenced the development of modern canyons. The buried canyons are infilled along nine slope-wide unconformities separating upper-middle Miocene to Pleistocene sediments that thin downslope. Canyons infilled during the Miocene
Authors
Lincoln F. Pratson, William B. F. Ryan, Gregory S. Mountain, David C. Twichell
Meteoroid mayhem in Ole Virginny: Source of the North American tektite strewn field
New seismic reflection data from Chesapeake Bay reveal a buried, 85-km-wide, 1.5-2.0-km-deep, peak-ring impact crater, carved through upper Eocene to Lower Cretaceous sedimentary strata and into underlying pre-Mesozoic crystalline basement rocks. A polymictic, late Eocene impact breccia, composed mainly of locally derived sedimentary debris (determined from four continuous cores), surrounds and pa
Authors
C. Wylie Poag, David S. Powars, Lawrence J. Poppe, Robert B. Mixon
Stratigraphy of the Mississippi-Alabama shelf and the Mobile River incised-valley system
The Mobile River incised-valley system located in the northern Gulf of Mexico occupies an area from southern Alabama through Mobile Bay to the outer Mississippi-Alabama continental shelf. During the Wisconsinan regression, this incised-valley system was fluvially eroded and extended across the exposed shelf to a shelf-margin delta complex. The last postglacial transgression drowned the entrenched
Authors
Jack L. Kindinger, Peter S. Balson, James G. Flocks
Acoustic mapping as an environmental management tool: I. detection of barrels of low-level radioactive waste, Gulf of the Farallones National Marine Sanctuary, California
The oceans have been and will continue to be disposal sites for a wide variety of waste products. Often these wastes are not dumped at the designated sites or transport occurs during or after dumping, and, subsequent attempts to monitor the effects the waste products have on the environment are inadequate because the actual location of the waste is not known. Acoustic mapping of the seafloor with
Authors
Herman A. Karl, William C. Schwab, A. St. C. Wright, David E. Drake, John L. Chin, William W. Danforth, Edward Ueber
Geochemical changes in crude oil spilled from the Exxon Valdez supertanker into Prince William Sound, Alaska
North Slope crude oil spilled from the T/V Exxon Valdez in March 1989 and contaminated about 500 km of Prince William Sound shoreline. Aliphatic and aromatic hydrocarbons in oil samples collected in August 1990 and June 1992 from beaches on six islands impacted by the spill have been compared with the hydrocarbons from North Slope crude oil taken from the stricken tanker. Degradation processes hav
Authors
Frances D. Hostettler, Keith A. Kvenvolden
Decade-scale trend in sea water salinity revealed through d18O analysis of Montastraea annularis annual growth bands
Stable oxygen isotope ratios (1)180) of coral skeletons are influenced by ambient water temperature and by the oxygen isotope ratio in the surrounding sea water, which, in turn, is linked to evaporation (salinity) and precipitation. To investigate this relationship more thoroughly, we collected hourly temperature data from the Hen and Chickens Reef in the Florida Keys between 1975 and 1988 and com
Authors
Robert B. Halley, Peter K. Swart, Richard E. Dodge, J. Harold Hudson
Vertical structure of mean cross-shore currents across a barred surf zone
Mean cross-shore currents observed across a barred surf zone are compared to model predictions. The model is based on a simplified momentum balance with a turbulent boundary layer at the bed. Turbulent exchange is parameterized by an eddy viscosity formulation, with the eddy viscosity Aυ independent of time and the vertical coordinate. Mean currents result from gradients due to wave breaking and s
Authors
John W. Haines, Asbury H. Sallenger