Appendix A 



Glossary of Geologic Terms 



ANGLE OF REPOSE The maximum slope at which cohesionless sediments 

 are stable. 



ARCH A rock feature in the form of an arch lying close offshore. The form 

 and isolation are products of marine erosion. 



AVULSION A tearing away. Often refers to a rapid change in a river's 

 course. 



BACK BARRIER Pertaining to the lagoon-raarsh-tidal creek complex in the 

 lee of a coastal barrier island, barrier spit, or baymouth barrier. 



BARCHAN DUNE A dune of crescentic shape with the convex side facing 

 the prevailing wind. 



BEACH CUSPS One of a series of low mounds separated by crescentic- 

 shape troughs spaced at regular intervals along a beach. 



BEDFORMS Any deviation from a flat bed that is readily detected by eye, 

 e.g., ripple marks, sand waves. 



BIOEROSION Erosion of rocks or sediment created by biological activity, 

 especially boring organisms. 



BIOGENIC Of biological origin. Usually sediments composed of the hard 

 parts of plants or animals and organic reef masses. 



BIOTURBATION The disturbance of sediment bedding by the activities of 

 burrowing organisms. 



BLOWOUTS Places in vegetated dunes or sand flats where bare spots occur 

 and are subjected to wind erosion. 



BRYOZOA Invertebrate belonging to the Phylum Bryozoa and characterized 

 by colonial growth and a branching, twiglike skeleton. 



Appendix A Glossary of Geologic Terms 



A1 



