REGIONAL GEOLOGY OF THE SOUTHERN LAKE ERIE (OHIO) BOTTOM: 

 A SEISMIC REFLECTION AND VIBRACORE STUDY 



by 



Charles E. Carter, S. Jeffress Williams, 

 Jonathan A. Fuller, and Edward P. Meisburger 



I . INTRODUCTION 



1. Background and Scope . 



The construction, improvement, and periodic maintenance of beaches and 

 dunes by the placement (nourishment) of suitable sand along the shoreline is 

 an important means of counteracting coastal erosion and enhancing recreational 

 facilities. However, it has become increasingly difficult in recent years to 

 obtain suitable sand from traditional sources such as lagoons and inland 

 deposits because of economic and ecological factors. This problem led the 

 U.S. Army Coastal Engineering Research Center (CERC) to initiate a search for 

 offshore sand deposits. Exploratory efforts to locate and inventory deposits 

 suitable for future fill requirements began in 1964 with a survey off the New 

 Jersey coast (Duane, 1969) . Subsequent data collection surveys have included 

 the Inner Continental Shelf areas off New England, Long Island, Delaware, 

 Maryland, Virginia, Florida, the Cape Fear region of North Carolina, eastern 

 Lake Michigan, and southern California. This program, formerly known as the 

 Sand Inventory Program, is now known as the Inner Continental Shelf Sediment 

 and Structure (ICONS) program. 



The type of data collected for the ICONS program is not only useful in 

 locating potential borrow areas but is of further value in providing geological 

 information for planning, design, and environmental impact evaluation of coastal 

 engineering works. The results of the ICONS studies are normally presented in 

 two separate but complementary reports: one covering sand resources, the other 

 covering the regional geology. 



This study is unique from the previous ICONS studies in that it was con- 

 ducted in cooperation with a State geological survey, the Ohio Department of 

 Natural Resources, Division of Geological Survey (DCS). The report deals 

 primarily with the bottom and subbottom deposits in the Ohio waters of Lake 

 Erie as mapped largely from high-frequency seismic reflection profiles and 

 vibracores between Conneaut (at the Ohio-Pennsylvania border) and Marblehead. 

 The report does not include the reach between Marblehead and Toledo. Seismic 

 profiling of this reach was done, but no vibracores were taken and the seismic 

 records are difficult to interpret because of the lack of well-defined reflec- 

 tors. The lack of well-defined reflectors on the records between Vermilion and 

 Marblehead also precluded mapping of the subbottom deposits along this stretch 

 of shore. This report follows a report on sand resources in Ohio (Williams, 

 et al., 1980) and another report on the Pennsylvania part of Lake Erie 

 (Williams and Meisburger, 1982) . 



The study area encompasses a zone ranging from 1 to 16 kilometers offshore 

 between Conneaut and Marblehead (Fig. 1). Survey coverage of the area is shown 



