Application of Geographic Information System to Exploration Studies in Sedimentary Basins

Betty M. Miller

The U.S. Geological Survey (USGS) is currently exploring the feasibility of applying Geographic Information Systems (GIS) technology to the development of a working prototype system that will provide the framework for three-dimensional analysis of sedimentary basins. GIS technology involves the integration of mapping and database functions that enable the user not only to integrate and manipulate spatial (coordinate) data with attribute (thematic) data to combine complex geographic, geologic, and geophysical data sets into resultant overlay and composite maps but also to conduct multivariate exploratory data analysis and have access to a variety of options for analyzing these databases.

The San Juan basin, a 13,500-mi² Laramide structural basin in northwestern New Mexico and southwestern Colorado, was chosen for the pilot project. The basin encompasses a maximum of over 15,000 ft of Paleozoic to Eocene sedimentary rock and contains economic deposits of natural gas, oil, coal, and uranium. Successful exploration in this basin requires an understanding of the complex stratigraphy and structural geology controlling the distribution of these resources.

GIS technology applied to the San Juan basin includes both surface and subsurface data sets that establish a three-dimensional perspective of the basin's fundamental stratigraphic and structural framework and aid in the identification of the basins temporal and tectonic relationships relative to origin and occurrence of its resources. Among the digital databases used for surface mapping is the US GeoData system from the USGS's National Mapping Program, which includes Digital Elevation Models (DEM) for terrain elevations; Digital Line Graphs (DLG) for planimetric information on boundaries, transportation, hydrography, and the U.S. Public Land Survey System; and Land Use and Land Cover (LULC) data. Additional databases used for surface mapping include surficial geology, locations of oil and gas wells, well status, and oil and gas fields. Databases for subsurface mapping include structure contour, isopach, and facies maps for the major oil- and gas-producing formations (Pictured Cliffs, Gallup and Dakota Sandstones, and Mesaverde Group); cross sections; paleogeographic reconstructions; geophysical and geochemical maps; and composited map products. Current technology and software being used include the GIS ARC/INFO system on the PRIME computer, the Petroleum Information-Well History Control System (PI-WHCS) well database, and mapping software such as Interactive Surface Modeling (ISM) and Triangulated Irregular Network (TIN).

GIS technology provides the geologist with new tools for innovative research in geologic interpretation, for updating information databases, for development of new concepts in basin analysis, and for applications to new resource appraisal methodology.

AAPG Search and Discovery Article #91023©1989 AAPG Eastern Section, Sept. 10-13, 1989, Bloomington, Indiana.