Kentucky Geological Survey Categorizing and Documenting Geologic Map Discontinuities

Abstract: Kentucky Geological Survey Categorizing and Documenting Geologic Map Discontinuities Doug Curl, PI and William Andrews, Kentucky Geological Survey ([email protected], [email protected] ) The Kentucky Geological Survey proposes to utilize our existing detailed statewide digital geologic map dataset—digitized from hard copy maps produced in a USGS-KGS effort from 1960 to 1978—to identify and categorize the conceptual origins of polygon busts, compile best-practice options for resolution of busts, and develop appropriate metadata and documentation. The original mapping process included more than 200 geologic field mappers over 18 years, and multiple sources for quadrangle-boundary disagreements developed. This project will reexamine each “bust,” identify the conceptual origin of the bust (eg. Nomenclature change, geologic marker bed transition, expanding/collapsing stratigraphic section, lumping/splitting, etc). For each different type of bust origin, we will explore the best options for resolution including reconciliation with GeoLex and adjacent published geologic maps. We will develop a model of metadata and documentation to identify the type and origin of busts identified. Taken together, these products can provide a strong basis for a national consideration of the necessary tasks for reconciling the State Geologic Map Compilation or similar multi-jurisdictional compilation datasets. This project will focus on intra-state issues developed from the original field mapping and subsequent (and separate) digitization process. To achieve our objective, KGS will hire a Temporary Geologist GIS Technician to examine the contact line and geologic unit polygons from the KGS Digital Vectorized Geologic Quadrangle (DVGQ) data and develop metadata at the feature level describing why decisions were made to eliminate geologic unit busts, and also create features and metadata describing why decisions were made to maintain busts between quadrangle boundaries. Curl, Andrews, and KGS stratigrapher, Steve Greb, will provide input and consult about GIS techniques and software, geologic mapping questions, and stratigraphic issues. Along with updated DVGQ data, KGS will also develop a data schema and metadata structure for handling this type of information, which other geologic surveys could adopt for similar issues. Based on this work KGS will also develop a nomenclature and rubric for describing bust types.