Northeastern Section (45th Annual) and Southeastern Section (59th Annual) Joint Meeting (13-16 March 2010)
Paper No. 25-9
Presentation Time: 1:30 PM-4:15 PM

VARIABLES AFFECTING GROWTH OF LITTORAL SPITS

GALVIN, Cyril, Coastal Engineer, Box 623, Springfield, VA 22150, galvincoastal@juno.com

A littoral spit is a narrow peninsula of sand and/or gravel directed parallel to the general shoreline, attached to the main shore at its updrift end, and isolated in the open water at its downdrift end. The two main factors affecting the growth of littoral spits are: (1) abundant source of sand and possibly gravel, and (2) longshore transport dominantly in one direction (equivalent to saying that the site is sheltered from waves in the opposite direction). Sites with recent beach nourishment are good candidates for spit growth. Littoral spits are well developed on tideless lake and tidal ocean shores, so tide range is not likely to be a first order factor determining spits. Spit growth will be favored where nearshore profiles are flatter.

The littoral spit detaches from the main shore at a surprisingly small angle -- typically ten degrees or less at point of tangency. This is similar to the typical angle of nearshore depth-controlled wave breaking. It suggests that littoral spits owe their development to sediment-laden longshore currents whose momentum flux overpowers cross shore factors.

Northeastern Section (45th Annual) and Southeastern Section (59th Annual) Joint Meeting (13-16 March 2010)
General Information for this Meeting
Session No. 25--Booth# 72
Measuring and Modeling Coastal Morphodynamics: Beaches and Shelves (Posters)
Sheraton Baltimore City Center: International ABCDF
1:30 PM-4:15 PM, Sunday, 14 March 2010

Geological Society of America Abstracts with Programs, Vol. 42, No. 1, p. 95

© Copyright 2010 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.