INTRODUCTION
A principal concern of the Committee Advisory to the U.S. Geological Survey (USGS) was that the activity that lends its name to both federal and state geological surveys appears to be declining in the federal survey. This is particularly disturbing because it is the committee’s perception that the need for a vigorous geologic mapping program is great, although the extent of need has not been determined. In the most fundamental terms, the federal and state surveys were created to conduct geological surveys and to prepare maps and reports based on their findings. The initial objective was assessment of mineral resource potential. Today geologic maps—the fundamental geologic information—serve a significantly expanded role and are a principal guide to most human interactions with the Earth, including the environment, land use, energy and mineral resources, natural hazards, and water resources. However, less than 20 percent of the nation is mapped at the standard 1:24,000 scale.
Because of the constant acquisition of new information, changing concepts, changing technology, and evolving needs, geology is an unending subject of research; and geologic maps are subject to constant review and periodic revision.
For the purposes of program analysis, the committee defines geologic mapping as the preparation of a map from field surveys and other sources of information on which is recorded geologic information such as the distribution, nature and age of rock units, and the occurrence of structural features, mineral deposits, and fossil localities. As such, geologic maps present carefully and competently compiled and well organized geologic information of a basic and/or interpretive nature.
A geologic mapping program should be responsive to society’s needs. Given that these needs have changed and will continue to change, it seems equally apparent that those responsible for geologic mapping should recognize the changing character of this “need” and that it be periodically reexamined and redefined. An NRC committee surveyed the mapping needs of the general geologic community; the final report is in preparation.
The principal elements of a geologic mapping program follow logically from a need and should include a clearly defined statement of mission and objectives, a listing of priorities, and a plan.
