USGS1987
This map brings together data from all known reports on landslides in Alabama mentioned by Alger and Brabb (1985) and information provided by State and County Highway Departments in response to a questionnaire sent in 1981 by K. F. Rheams. Additional landslide data from the northern part of the state and from Jefferson County were added by Fred Taylor and E. E. Brabb from reports by Pomeroy (1982), Thomas (1979, 1982), and Szabo and others (1979). The locations of two landslides were provided by the U.S. Forest Service (written commun., 1982), and a few more additional landslide locations were noted by K. F. Rheams in 1981 and by E. E. Brabb in 1982. Locations of landslides from the various data sources were transferred to this map by measuring the distance from known landmarks. Substantial differences in scale, differential swelling and shrinking of paper source maps, and other technical problems in transferring the landslide data may have led to errors of as much as one mile in plotting the locations. The landslide locations, therefore, are located only approximately. Many more landslides exist in Alabama but have not yet been recognized or recorded in public documents. The absence of a landslide symbol on this map, therefore, does not indicate that an area is necessarily free of landslides. Conversely, the clustering of landslide symbols in an area should not be used to indicate that the area is unsafe, but rather that many landslides have been reported and that investigation of the problem by qualified geologists and engineers is prudent before development takes place. This map should be considered preliminary in the sense that a systematic evaluation of all areas in Alabama for landslides using standard photographic interpretation techniques has not yet been done. The user of this map is referred to Pomeroy and Thomas (1935) for a discussion of slope—stability problems in northern Alabama.