Migration of Tidal Sand Waves in Chesapeake Bay Entrance
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.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 15, 1971
- Accession Number
- AD0734701
Entities
People
- John C. Ludwick
Organizations
- Old Dominion University