Tidal Currents and Zig-Zag Sand Shoals in a Wide Estuary Entrance.

Abstract

Fourteen 27-hour tidal current stations were occupied in the entrance to Chesapeake Bay in a 40-square mile area of subtidal sand banks and channels where the average water depth is 21 feet. Near the bottom at most stations, flood flow dominates over ebb flow in both peak speed and duration. Velocity profiles from bottom to surface are fitted by a parabolic-shaped velocity defect law from which shear stress at the bed was estimated. With two exceptions, net transport of bed sediment is ebb-directed. Decrease in net sediment transport rate along the path of net motion requires deposition of sediment. Locations of deduced deposition correspond to shoals. Prominent indentations, or sinuses, in the margins of shoals, are strongly dominated by net sediment transport towards the closed end of a channel. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 15, 1973
Accession Number
AD0755735

Entities

People

  • John C. Ludwick

Organizations

  • Old Dominion University

Tags

DTIC Thesaurus Topics

  • Bays
  • Chesapeake Bay
  • Physical Properties
  • Sedimentation
  • Sediments
  • Shear Stresses
  • Stresses
  • Tidal Currents
  • Transport Ships

Fields of Study

  • Geology

Readers

  • Coastal Oceanography
  • Hydraulic Engineering.
  • Materials Science (Mechanical Engineering).