The sand percent contours were produced by the Louisiana Geological Survey and were digitized from Chapter 11, Cenozoic, in The Gulf of Mexico Basin, Volume J, The Geology of North America (1991). The data are provided in three shapefiles--one for each stage (Lower, Middle and Upper) of the Miocene series.

These datasets contain basic data and interpretations developed and compiled by the U.S. Geological Survey's Framework Studies and Assessment of the Gulf Coast Project. Other major sources of data include publicly available information from state agencies as well as publications of the U.S. Geological Survey and other scientific organizations. In cases where company proprietary data were used to produce various derivatives such as contour surfaces, the source is cited but the data are not displayed.

This is a region dataset delineating the areas of offshore Louisiana and Texas having Regional Response Team VI (RRT 6) pre-approval for the use of dispersants to break up an oil spill. This area is defined as that area of no less than 10 meters depth and at least three nautical miles from the nearest shoreline, out to the limit of the Exclusive Economic Zone. Three nautical miles from the nearest shoreline for Louisiana corresponds to the state's territorial limits. This data set is bounded on the west by the Galveston Marine Safety Office zone and on the east by the Mobile Marine Safety Office zone. The attributes of the boundary arcs indicate the source of each section of the boundary.