HR: 1340h
AN: H43A-0359    [Abstracts]
TI: Variations and Dependency of Sedimentary Processes and Morphology of the Hudson River Estuary
AU: * Nitsche, F O
EM: fnitsche@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 United States
AU: Bell, R
EM: robinb@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 United States
AU: Ryan, W B
EM: billr@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 United States
AU: Carbotte, S M
EM: carbotte@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 United States
AU: Bertinato, C
EM: bertinato@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 United States
AU: Flood, R
EM: Roger.Flood@stonybrook.edu
AF: Marine Science Center, State University of New York, Stony Brook, 157 Endeavour Hall, Stony Brook, NY 11794 United States
AB: The morphology of rivers and estuaries is controlled by many factors including bedrock geology, flow conditions, and sediment input. The 240 km long Hudson River Estuary crosses different types of bedrock, and its sediment transport is strongly influenced by tidal currents and strong runoff events. The small contribution of tributary input in the estuarine part of the Hudson River allows to compare the relative influence of these different factors on morphology and sedimentary processes. A comprehensive data set including multibeam bathymetry, sidescan sonar, a dense network of sub-bottom profiles, and over 500 sediment cores and grab samples has been acquired as part of the Hudson River Benthic Mapping Project funded by the New York State Department of Environmental Conservation. Based on these data we describe and compare important factors and their changes such as grain size distribution, morphology, bedrock geology, and depositional and erosional environments. We see a distinct change in grain size distribution from sand to mud-dominated sediment composition that corresponds to a morphological change from a meandering and bar-building channel to a straighter channel with large estuarine embayments. The dominating sedimentary processes vary more often than the grain size composition and there is an apparent correlation of these variations with changes in the surrounding bedrock geology and related morphology. In addition to natural variations, a canalized section of the Hudson River shows the influence of human alteration on the morphology and possibly on related sediment transport.
DE: 4235 Estuarine processes
DE: 3022 Marine sediments--processes and transport
DE: 3045 Seafloor morphology and bottom photography
DE: 1815 Erosion and sedimentation
DE: 1860 Runoff and streamflow
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting