The Geologic Mapping Act was reauthorized by the Congress and was signed by the President in 1997 (Public Law 105-36). This was a clear signal that our national leadership continues to recognize the urgent need for up-to-date, accurate, and detailed geologic mapping in the United States of America. The Association of American State Geologists (AASG) strongly supports and advocates accelerated geologic mapping throughout the nation. Both the U.S. Geological Survey (USGS) and AASG recognize that modern geologic maps are essential for dealing with critical public concerns including ground-water supplies, energy and mineral resources, geologic hazards, waste management, and environmental protection.
In addition, the USGS and AASG recognize that today's electronic world requires delivery of geologic-map information in digital form so that it can be used in geographic information systems (GIS). In response to that need and to the requirements of the Geologic Mapping Act, the USGS established the National Geologic Map Database (NGMDB) Project to deliver geologic spatial data in digital form. This requires the development of a whole suite of standards so that, "...archival information can be accessed, exchanged, and compared efficiently and accurately..." (PL 105-36). The AASG also responded by establishing the Digital Geologic Mapping Committee to help establish and construct the NGMDB in cooperation with the USGS. Six cooperative NGMDB working groups were formed in 1996 and the progress of those groups is elaborated in Progress Toward Development of the National Geologic Map Database by Soller and Berg in this collection of papers.
In 1997, the Data-Capture Working Group convened a Digital Mapping Techniques '97 (DMT'97) workshop at Lawrence, Kansas (hosted by the Kansas Geological Survey). The workshop, which was documented in USGS Open-File Report 97-269, was so successful that a second USGS-AASG Digital Mapping Techniques '98 (DMT'98) workshop was held in Champaign, Illinois, hosted by the Illinois State Geological Survey. The results of the DMT'98 workshop are documented in this collection of papers. As the Digital Mapping Techniques workshops are evolving, one aspect seems to be very important in their success --- informality. Lots of time is available for one-on-one discussions, and personal experience in the digital-mapping world is freely shared. We look forward to DMT'99.