The New Orleans Barrier Island underlying the City of New Orleans has been sampled in surface exposures and by coring throughout 10 miles of its length which lies approximately east-west. Its width is 3 miles. Maximum thickness is 35 feet.

Radiocarbon dates demonstrate that this island was a contemporary of Maringouin and Teche phases of the Mississippi River and was buried by the younger sediments that built the Metairie subdelta.

Additional features are the associated fauna of open-gulf types; median grain size too large to be ascribed solely to a Mississippi River source, and a sequence of

End_Page 1963------------------------------

grain-size increase from bottom to top; heavy-mineral content related to an Eastern Gulf source; and sedimentary structures comprising mainly cross-bedding of shallow dip to horizontal bedding.

End_of_Article - Last_Page 1964------------