ABSTRACT
The Mississippi-Alabama Marine Ecosystem Study was a multidisciplinary benchmark survey of the middle and Outer Continental Shelf south of the coasts of those states, funded by the Minerals Management Service of the Department of the Interior. From prior geophysical and geological studies it was known that the region contains topographic features and "hardbottoms". Geological characterization of the study area was based on two types of data, side-scan sonar acoustic images of the sea floor and high-resolution reflection profiles of the upper sediment layers. Two primary types of sea floor backscatter were identified within the study area: homogeneous and patchy. Sea floor producing homogeneous backscatter is uniform in appearance on the side-scan sonar images and has been subdivided into four classes by return strength: low, moderate, moderate-high, and high. Patchy backscatter ranges in appearance from random "splotches" to regular sublinear "waves".
