Shoreline Characterization of the Geomorphological Impact of Hurricane Georges on the Chandeleur Islands: Southeast Louisiana
J. Koch1 and S. Penland2
1Florida State University, Tallahassee, Florida
2University of New Orleans, New Orleans, LA
The Chandeleur Islands located in southeast Louisiana are the oldest and longest transgressive barrier island arc in the Mississippi River Delta plain. This barrier island system was created as a result of the abandonment and transgression of the St. Bernard Delta Complex of the Mississippi River. The St. Bernard Delta Complex was abandoned 1.8 ka due to the process of delta switching which resulted in the formation of the Chandeleur Island barrier arc system. The Chandeleur Islands are the subaerial portion of an extensive sand body that overlies a thick sequence of lagoonal deposits deposited atop the subsiding St. Bernard Delta Complex. The Chandeleur Islands are a Stage II transgressive barrier island arc. The overall objectives of this study are to document the geomorphological impact of Hurricane Georges on the Chandeleur Islands and to document initial island recovery. These objectives will be achieved by utilizing aerial videotape surveys. Hurricane Georges impacted Chandeleur Island on September 27-29, 1998, causing extensive erosion and landscape changes. Hurricane Georges created numerous erosional and depositional features, including washover channels and fans and scour holes with channels and depositional rims. The dunes were completely destroyed. The beaches narrowed. With initial recovery, beaches began to build back and spits formed to close some of the channels. Hurricane Georges also created numerous wave dominated tidal inlets through which sediments were transported onto the back barrier platform. This study documents the importance of the prestorm barrier island geomorphology in controlling the location and distribution of storm impact features.
AAPG Search and Discovery Article #90901©2001 GCAGS, Annual Meeting, Shreveport, Louisiana