Saint Charles Bay Quadrangle, Texas

OFM0225. Geologic Map of the Saint Charles Bay Quadrangle, Texas Gulf of Mexico Coast, by J. G. Paine and E. W. Collins. Oversize color geologic map on topographic base, map scale 1:24,000, 2016.

To purchase this map as a downloadable PDF, please order OFM0225D.

About This Map
This map illustrates the geology at the eastern margin of Copano Bay and includes part of the Aransas National Wildlife Refuge and Goose Island State Park. The area also includes the 1.5-mi-wide Saint Charles Bay. Geology of the quadrangle consists of sediments deposited within a Pleistocene barrier system and a Holocene bay-estuary system. Pleistocene Beaumont fluvial–deltaic clay-rich facies occur at the northwest part of the map. Surface expression of the Pleistocene barrier sediments indicates closed basins, drainageways, and southwest–northeast-trending ridges and swales. Holocene tidal-flat and bay-margin deposits—including spit, beach, washover-fan and clay-dune deposits—occur along Saint Charles Bay, Carlos Bay, and the Intracoastal Waterway. Man-made features mapped include pits and excavations, selected canals and channels dug for navigation or drainage, land artificially elevated by fill, dredged material, and a protective rock structure.


Keywords: maps, geologic maps, quadrangle maps, Saint Charles Bay, Copano Bay, Carlos Bay, Intracoastal Waterway, Texas Coast, Aransas National Wildlife Refuge, Goose Island State Park

Citation
Paine, J. G., and Collins, E. W., 2016, Geologic Map of the Saint Charles Bay Quadrangle, Texas Gulf of Mexico Coast: The University of Texas at Austin, Bureau of Economic Geology, Open-File Map No. 225, map scale 1:24,000.