عنوان
پدید آورنده
موضوع
رده
کتابخانه
محل استقرار
TLpq303611748
انگلیسی
MORPHOLOGY AND SEDIMENT CHARACTER OF MESOTIDAL SHORELINE DEPOSITIONAL ENVIRONMENTS (SOUTH CAROLINA; NIGERIA)
[Thesis]
W. J. Sexton
University of South Carolina
1987
314
Ph.D.
University of South Carolina
1987
This dissertation comprises the text from three studies on clastic depositional systems with emphasis on deltaic sedimentation from three different study sites: (1) Niger Delta; (2) Santee Delta inner shelf; and (3) tidal deltas on the central South Carolina coastline. The Niger Delta encompasses one-half of Nigeria's 800-kilometer (km) shoreline and is one of the larger and better-developed arcuate river deltas in the world. The shoreline of Nigeria was divided into five distinct geomorphological regions based on coastal geomorphology and sedimentological parameters. The morphological regions from west to east coasts are (1) barrier-lagoon coast, (2) transgressive mud coast, (3) delta flanks, (4) arcuate delta, and (5) strand coast. Three subtidal shoal deposits seaward of Bull Island, Cape Romain and Santee Delta, off the South Carolina Coast have been influenced by inner-shelf wave and tidal processes since these features were flooded during the late Pleistocene/Holocene rise in sea level. Analysis of the bottom surface sediment samples revealed that sediments ranged from silt to gravel-size material. The bottom is highly variable with the most pronounced feature being the seaward terminus of the sediment lobes. Core data collected revealed sharp contrasts in depositional environments. On the sediment lobes below the marine sand are fresh-to-brackish-to open marine water deposits. The Holocene coastal sand deposits of the central South Carolina coastline were investigated to estimate volumes of reservoir-quality (RQ) sediments. These sand bodies, which vary considerably in size, thickness, shape, and continuity, were deposited in a variety of depositional settings including barrier islands, tidal deltas, exposed sand flats, tidal sand ridges, and tidal point bars. Minimum potentials to identify and RQ sediment for each sand-body type was a conservative mud cutoff value of 15 percent. Of the 6 most significant RQ depositional environments ebb-tidal delta complexes (delta and channel fill) accounted for 77 percent of all RQ sediments in the study area. If the Holocene sand deposits along the central 50 mi (80 km) of the South Carolina coast were preserved in place a total of 1.3 usd\timesusd 10 ac-ft of RQ sands would have been deposited.
Earth sciences
Geology
W. J. Sexton
مطالعه متن کتاب p
[Thesis]
276903
a
Y
