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Publications

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Analysis of coral mucus as an improved medium for detection of enteric microbes and for determining patterns of sewage contamination in reef environments

Traditional fecal indicator bacteria are often subject to a high degree of die-off and dilution in tropical marine waters, particularly in offshore areas such as coral reefs. Furthermore, these microbes are often not associated with human waste, and their presence may not be indicative of health risk. To address the offshore extent of wastewater contamination in the Florida Keys reef tract, we ass
Authors
Erin K. Lipp, Dale W. Griffin

Hydrogeologic setting and ground water flow beneath a section of Indian River Bay, Delaware

The small bays along the Atlantic coast of the Delmarva Peninsula (Delaware, Maryland, and Virginia) are a valuable natural resource, and an asset for commerce and recreation. These coastal bays also are vulnerable to eutrophication from the input of excess nutrients derived from agriculture and other human activities in the watersheds. Ground water discharge may be an appreciable source of fres
Authors
David E. Krantz, Frank T. Manheim, John F. Bratton, Daniel J. Phelan

Los impactos de las actividades relacionadas con el petroleo y el gas en la disminucion de los humedales costeros del delta del Misisipi

No abstract available.
Authors
Jae-Young Ko, John Day, John Barras, Robert Morton, James Johnston, Gregory Steyer, G. Paul Kemp, Ellis Clairain, Russell Theriot

Where in the world are my field plots? Using GPS effectively in environmental field studies

Global positioning system (GPS) technology is rapidly replacing tape, compass, and traditional surveying instruments as the preferred tool for estimating the positions of environmental research sites. One important problem, however, is that it can be difficult to estimate the uncertainty of GPS-derived positions. Sources of error include various satellite- and site-related factors, such as forest
Authors
Chris E. Johnson, Christopher C. Barton

Assessment of estuarine water-quality indicators using MODIS medium-resolution bands: initial results from Tampa Bay, FL

Using Tampa Bay, FL as an example, we explored the potential for using MODIS medium-resolution bands (250- and 500-m data at 469-, 555-, and 645-nm) for estuarine monitoring. Field surveys during 21–22 October 2003 showed that Tampa Bay has Case-II waters, in that for the salinity range of 24–32 psu, (a) chlorophyll concentration (11 to 23 mg m−3), (b) colored dissolved organic matter (CDOM) absor
Authors
Chuanmin Hu, Zhiqiang Chen, Tonya D. Clayton, Peter W. Swarzenski, John Brock, Frank E. Muller-Karger

Holocene reef development where wave energy reduces accommodation

Analyses of 32 drill cores obtained from the windward reef of Kailua Bay, Oahu, Hawaii, indicate that high wave energy significantly reduced accommodation space for reef development in the Holocene and produced variable architecture because of the combined influence of sea-level history and wave exposure over a complex antecedent topography. A paleostream valley within the late Pleistocene insula
Authors
Eric E. Grossman, Charles H. Fletcher

[Book review] Sea level rise: history and consequences

Review of: Sea level Rise: history and consequences. Bruce Douglas, Michael S. Kearney and Stephen P. Leatherman (eds), Sand Diego: Academic Press, 2001, 232 pp. plus CD-RIM, US$64.95, hardback. ISBN 0-12-221345-9.
Authors
Eric E. Grossman

Textures of the soils and rocks at Gusev Crater from Spirit’s Microscopic Imager

The Microscopic Imager on the Spirit rover analyzed the textures of the soil and rocks at Gusev crater on Mars at a resolution of 100 micrometers. Weakly bound agglomerates of dust are present in the soil near the Columbia Memorial Station. Some of the brushed or abraded rock surfaces show igneous textures and evidence for alteration rinds, coatings, and veins consistent with secondary mineralizat
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. III Bell, P. Bertelsen, N.A. Cabrol, Lisa R. Gaddis, A. G. Hayes, S.F. Hviid, J. R. Johnson, K.M. Kinch, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, J. W. Rice, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, A. Wang

Magnetic properties experiments on the Mars Exploration Rover Spirit at Gusev Crater

The magnetic properties experiments are designed to help identify the magnetic minerals in the dust and rocks on Mars—and to determine whether liquid water was involved in the formation and alteration of these magnetic minerals. Almost all of the dust particles suspended in the martian atmosphere must contain ferrimagnetic minerals (such as maghemite or magnetite) in an amount of ∼2% by weight. Th
Authors
P. Bertelsen, W. Goetz, M.B. Madsen, K.M. Kinch, S.F. Hviid, J. M. Knudsen, H.P. Gunnlaugsson, J. Merrison, P. Nørnberg, S. W. Squyres, J. F. III Bell, Kenneth E. Herkenhoff, S. Gorevan, A. S. Yen, T. Myrick, G. Klingelhoefer, R. Rieder, R. Gellert

Using twelve years of USGS refraction lines to calibrate the Brocher and others (1997) 3D velocity model of the Bay Area

Campbell (1983) demonstrated that site amplification correlates with depths to the 1.0, 1.5, and 2.5 km/s S-wave velocity horizons. To estimate these depths for the Bay Area stations in the PEER/NGA database, we compare the depths to the 3.2 and 4.4 km/s P-wave velocities in the Brocher and others (1997) 3D velocity model with the depths to these horizons determined from 6 refraction lines shot in
Authors
John Boatwright, Luke Blair, Rufus Catchings, Mark Goldman, Fabio Perosi, Clare Steedman