Accession Number : AD0734701

Title :   Migration of Tidal Sand Waves in Chesapeake Bay Entrance.

Descriptive Note : Technical rept.,

Corporate Author : OLD DOMINION UNIV NORFOLK VA INST OF OCEANOGRAPHY

Personal Author(s) : Ludwick,John C.

Report Date : 15 NOV 1971

Pagination or Media Count : 74

Abstract : Subtidal sand waves occur atop shoals and on shoal margins in the northern part of the tidal entrance to Chesapeake Bay, Virginia. Wavelength ranges from 200-800 ft; height ranges from 5-11 ft. All major slopes are 2-3 degrees, far less than the angle of repose of the constituent sediment. In flood-dominated tidal channels, sand waves are asymmetrical and face landwards; in ebb-dominated tidal channels and atop most banks, sand waves face seawards. Where near-bottom flood and ebb tidal currents are equal in time-velocity impulse, sand waves of symmetrical trochoidal profile are developed. Data from 21 successive echo-sounding profiles taken over a 17-month period show that the seaward-facing asymmetrical sand waves range from 115 to 492 ft/year. (Author)

Descriptors :   (*SAND, *TIDES), (*CHESAPEAKE BAY, SAND), SEDIMENTATION, BATHYTHERMOGRAPH DATA, HYDROGRAPHIC SURVEYING, FLOODS, PARTICLE SIZE, SAMPLING, DENSITY, OCEAN CURRENTS, ESTUARIES, VIRGINIA

Subject Categories : Physical and Dynamic Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE