CONTENTS 



Page 



CONVERSION FACTORS, U.S. CUSTOMARY TO METRIC (SI) 6 



I INTRODUCTION 7 



Scope " 10 



II BACKGROUND 10 



1. Equipment and Field and Laboratory Procedures .... 10 



2. Geographic Setting 23 



3. Geologic Setting and Regional Stratigraphy 24 



III RESULTS 28 



1. Continental Shelf Morphology 28 



2. Shallow Subbottom Structure and Stratigraphy 28 



3. Primary Sediment Classes 31 



4. Suitability o£ Sandfill for Beach Nourishment .... 36 



5. Dredging Effects on the Shore 36 



6. Potential Offshore Sand Borrow Sites 38 



IV SUMMARY AND RECOMMENDATIONS 49 



LITERATURE CITED 50 



APPENDIX 



A CORE SEDIMENT DESCRIPTIONS 53 



B GRANULOMETRIC DATA AND CUMULATIVE CURVE PLOTS 71 



TABLES 



1 Grain-size scales (soil classification) 34 



2 Characteristics of possible borrow sites 41 



FIGURES 



1 Sections of the Texas gulf coast from High Island to Freeport 



which are experiencing severe beach erosion 8 



2 Photo showing the effects of beach erosion at Surf side Beach. . . 9 



3 Bathymetric map of the Texas inner shelf between High Island 



and Freeport H 



4 Schematic of a seismic reflection instrument being towed along 



a profile line l-^ 



5 The Galveston District survey boat, Vollevt, used to collect 



the seismic reflection data and to locate core sites for 



phase II • ■'■4 



