APPENDIX A: DISCUSSION AND ANNOTATED 

 BIBLIOGRAPHY OF OVERWASH LITERATURE 



Introduction 



1. Overwash is defined by the American Geological Institute (Bates and 

 Jackson 1980)* as: 



a. A mass of water representing the part of the uprush that runs 

 over the berm crest (or other structure) and that does not 

 flow directly back to the sea or lake. 



b. The flow of water in restricted areas over low parts of 

 barriers or spits, especially during high tides or storms. 



Although this definition applies to any low shoreline, including reef islands 

 or rocky spits, in this study only overwash along sandy barrier beaches, 

 especially if a frontal duneline is present, is discussed. 



2. A washover is the geomorphic feature produced by an overwash event. 

 The passage through the duneline is called the throat (Figure Al). The fan 

 is the portion of the washover deposited on the island or beach interior 

 where the landward flow is unrestricted by topography (Figure Al). Effects 

 of coastal storms on beaches are progressive. Initial beach erosion and dune 

 scarping will be followed by slight overtopping of the lower portions of the 

 duneline as the water level and wave runup increase. With continued water 

 level rise, significant dune overtopping will occur, with associated fan 

 deposition (Figure A2 ) . If the surge level rises enough, complete over- 

 topping of the duneline will occur, possibly resulting in total erosion of 

 the frontal dune. Significant storm duration without an increase in surge 

 level may produce a similar progression of effects, with dune erosion causing 

 overwash to occur at lower water levels. If landward flow of water is 

 concentrated in one area, deep erosion of an overwash throat may occur, 

 resulting in formation of a tidal inlet, although most tidal inlets formed 

 during storms result from seaward flow of elevated bay water (Hite 1924, 

 Pierce 1970). 



3. Most early research on overwash was primarily qualitative; whereas 



c References cited in the Appendix are included in the References at the end 

 of the main text. 



Al 



