Morphodynamics and Stratigraphy of Essex River EBB-Tidal Delta: Massachusetts
Abstract
The Essex River Inlet ebb-tidal delta system is a well-formed delta along a barrier island chain in the Merrimack Embayment. Sediments comprising this barrier island chain have been supplied primarily from reworking and onshore transport of the Early Holocene Merrimack River Delta. Southerly longshore currents have resulted in a fining grain-size trend to the south along the barrier chain as well as an increase in spacing of the offshore contours. The Essex River Inlet is anchored next to bedrock, and its ebb-tidal delta exhibits classic delta morphology whose environments respond to storms, tidal currents, wave processes, and sand transport. Distal portions of the delta including swash bars and terminal lobe are dominated by southerly and landward directed wave-generated currents. Wave refraction around the delta results in transport reversal approximately 1.2 km south of the main ebb channel. Intertidal sand bodies are dominated by landward-oriented currents with the exception of the distal channel margin linear bars. Sediment transport trends are dominated by gyres that involve sediment input from longshore currents into the updrift marginal flood channel, seaward sandwave migration through the main ebb channel, and onshore reworking of sediment through wave activity and swash bar migration.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1991
- Accession Number
- ADA241424
Entities
People
- J. B. Smith
Organizations
- Coastal Engineering Research Center