Data Mining Ammonite Localities to Build Chronostratigraphic Frameworks in the Western Interior Basin

Abstract

Geologic datasets are increasingly easier to access due to ongoing digitization efforts, yet utilization is still difficult due to the text- and figurebased nature of geologic data. Luckily, recent hardware and software advances enable geoscientists to integrate these datasets much faster and easier than before. To illustrate the power of data mining, a recommended workflow is presented which integrates newly-digitized USGS fossil localities with previously published datasets to create robust chronostratigraphic frameworks within the Western Interior basin. The workflow comprises six stages: (1) data compilation, (2) duplication of published well log correlations, (3) subsurfaceto- outcrop data integration, (4) standardization of interpretations, (5) data 41 Wyoming Geological Association – September 15-18, 2019 infilling, and (6) data expansion. To begin, the user needs to define a stratigraphic unit-of-interest (UOI) and geographic area for the project. Through an extensive literature search, well log correlations, stratigraphic sections, and geologic maps which include the UOI are tabulated and integrated using spreadsheets and a business analytics software package. The data is then overlain to define an initial area-of-interest (AOI) and a subsurface geological model is created by duplicating published well log correlations. These correlations are then integrated with outcrop data by creating a crosssection grid tied to stratigraphic sections. Geologic maps are utilized simultaneously to guide well log correlations, and ammonites are employed to troubleshoot incorrect correlations and standardize interpretations. Once a satisfactory answer has been reached, the AOI is infilled with additional data and expanded. Although the workflow is not inherently novel, it defines a systematic approach to data mining within the Western Interior Basin that highlights contradictory subsurface correlations and stratigraphic nomenclature. To demonstrate the process, a case study is presented which applies the recommended workflow to the Castlegate Member, Piceance basin, Colorado.

AAPG Datapages/Search and Discovery Article #90357 ©2019 AAPG Rocky Mountain Section Meeting, Cheyenne, Wyoming, September 15-18, 2019