High Resolution Geologic Mapping of Northeast Southern Michigan
F. Krist, Jr.1 and T. Black2
1Michigan Department of Natural Resources, Roscommon, MI
2Michigan Geological Survey, Gaylord, MI
Improved geologic mapping is possible through the integration of dissimilar data and enhanced processing capabilities found within Geographic Information Systems (GIS). This was demonstrated in part of Alcona, Alpena, Montmorency, and Presque Isle counties in northeastern Lower Michigan. Bedrock topography, drift thickness, bedrock geology, and formation structure surfaces were interpolated from various well data using the TOPOGRID command within the ARC/INFO GIS environment. The TOPOGRID command can generate a “hydrologically correct” topographic map that depicts the bedrock surface including the buried channels found on that surface. These channels are significant for aquifer delineation and protection, and have affected Antrim Shale gas production. Tolerance settings and the ability to turn off the drainage enforcement algorithm within TOPOGRID enable surfaces to be generated for bedrock formed under various conditions.
Michigan’s MIR oil and gas well database was filtered for data on formation top elevations and integrated with water well, outcrop, and geologic test hole data. Errors within the MIR database include multiple formation depth picks, missing elevations, and typos. A semi-manual process of reiteration between the well data, and the simulated structure and geologic surface maps was used to crosscheck and improve the accuracy of the interpolated maps.
AAPG Search and Discovery Article #90900©2001 AAPG Eastern Section Meeting, Kalamazoo, Michigan