A variety of map formats can display basic geologic and related environmental data derived from aerial photographs, detailed field investigations, and published and unpublished studies. These depictions provide information on natural environments for various types of environmental maps directed toward selected uses and audiences. Examples include:

1. Geology and Natural Environments of Padre Island National Seashore, Texas, which employs a typical map format of colors, symbols, and written descriptions to show the location and distribution of barrier-island and lagoon environments. Color photographs of each mapped environment provide visual reference for the intended popular audience composed of National Seashore visitors.

2. Sediment Distribution, Bathymetry, Faults, and Salt Diapirs: Submerged Lands of Texas, Galveston-Houston Sheet, which displays surficial sediments, water depth, and structural features using contours, colors, and symbols, with colors keyed to a unique color-coded

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sediment-classification diagram. The map also depicts the precise locations of the hundreds of sediment-sampling points from which data were obtained.

3. Composite Environmental Suitability Map: Brazoria County Geopressured-Geothermal Prospect Area, which uses a series of transparent-translucent overlay sheets on which specific environmental characteristics are shown in varying shades (intensities) of gray to map relative environmental suitability for geopressured-geothermal fluid production and disposal activities.

4. Lavaca and Lower Guadalupe River Basins Environmental Geologic Map, which consists of units that are defined in terms of substrate lithology, soils, landscape morphology, biologic assemblages, and geologic processes. Derivative maps prepared from the environmental geologic map include substrate materials, active geologic processes, and biologic assemblages.

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