Rapid sediment deposition and fine-scale strata formation in the Hudson estuary
Traykovski, Peter A.
Geyer, W. Rockwell
Sommerfield, Christopher K.
MetadataShow full item record
A 9 month time series of tripod-mounted optical and acoustic measurements of sediment concentration and bed elevation was used to examine depositional processes in relationship to hydrodynamic variables in the Hudson River estuary. A series of cores was also taken directly under and adjacent to the acoustic measurements to examine the relation between the depositional processes and the resulting fine-scale stratigraphy. The measurements reveal that deposition occurs as a result of sediment flux convergence behind a salinity front and that the accumulation rates are sufficient to deposit up to 25 cm of new high-porosity sediment in a single ebb-tidal phase. Subsequent dewatering and erosion reduces the thickness of the initial deposit to several centimeters. These depositional events were only observed on spring tides. Ten depositional events during two spring tidal cycles produced a seasonal deposit of 18 cm, consistent with estimates of seasonal deposition from cores. A proxy for near-bed suspended grain size variations was estimated from the combined acoustic and optical measurements, implying that the erosional processes resuspend only the finer-grained sediments, thus leaving behind silt and very fine grained sand beds. The thickness of the deposited homogenous clayey silt beds, and the vertical separation between beds interlaminated with silt and very fine sand, are roughly consistent with the acoustic measurements of changes in bed elevations during deposition and erosion. The variability in individual bed thickness is the result of variations of processes over an individual tidal cycle and is not a product of variations over the spring neap fortnightly timescale.
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 109 (2004): F02004, doi:10.1029/2003JF000096.
Showing items related by title, author, creator and subject.
The sediments of the western Gulf of Mexico. I. The continental terrace of the western Gulf of Mexico : its surface sediments, origin, and development. II. Chemical studies of sediments of the western Gulf of Mexico Stetson, Henry C.; Trask, Parker D. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1953-05)In 1947 the Woods Hole Oceanographic Institution organized an expedition to investigate the bottom sediments and oceanography of the northwest Gulf of Mexico. The Geological Society of America contributed to the support ...
Quantity, composition, and source of sediment collected in sediment traps along the fringing coral reef off Molokai, Hawaii Bothner, Michael H.; Reynolds, Richard L.; Casso, Michael A.; Storlazzi, Curt D.; Field, Michael E. (Elsevier B.V., 2006-03-20)Sediment traps were used to evaluate the frequency, cause, and relative intensity of sediment mobility/resuspension along the fringing coral reef off southern Molokai (February 2000–May 2002). Two storms with high rainfall, ...
Modern sedimentation in the Northern Barents Sea : input, dipersal and deposition of suspended sediments from glacial meltwater Pfirman, Stephanie L. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1984-08)The modern depositional environment of the northern epicontinental Barents Sea varies from proximal to distal glaciomarine. The regional surface sediment distribution is controlled by erosion of shallow banks of the ...