Talks at Colorado Scientific Society Meetings in 2025
CSS January 2025 Meeting
Geologic Map Derivatives: From Pen and Paper to Digital Databases
Thursday, January 16, 2025 at 7:00 pm
Michael Frothingham, U.S. Geological Survey, Geosciences and Environmental Change Science Center
This meeting was held at Calvary Church Golden.
Geologic Map Derivatives: From Pen and Paper to Digital Databases
Abstract: Geologic maps are venerable hallmarks of earth science. While traditional pen and paper maps have impressively withstood the test of time, they are currently undergoing a revolution as maps are compiled into integrated databases. These new digital databases are becoming increasingly accessible and user friendly, with queryable data that enables new scientific applications and analysis. I present three examples of derivative geologic maps, generated from geologic map data compiled in the Seamless Integrated Geologic Mapping extension to the Geologic Map Schema (SIGMa GeMS). Using attribute queries and spatial intersections in a geographic information system, derivative maps are created from 1:100,000-scale geologic map compilations within the footprints of Cortez, Durango, Trinidad, and Aztec 1×2 degree quadrangles in Utah, Colorado, and New Mexico. The derivative maps include: (1) an aggregate and infrastructure map, (2) a sand dune/sheet and infrastructure map, and (3) a surficial mass wasting deposits versus bedrock geology map. These maps illustrate where aggregate resources (e.g., unconsolidated gravel and sand) occur relative to civil infrastructure, identify areas where mobile landforms (e.g., sand dunes or sand sheets) pose potential future risks to roads, and explore correlations between surficial mass wasting deposits (e.g., landslides, rockfalls, debris flows, etc.) and the underlying bedrock geology. These examples demonstrate the utility of modern geologic map databases, highlight opportunities for improving subsequent mapping, and inspire the development of future derivative maps to address pressing geological problems and societal needs.
Michael G. Frothingham, PhD, joined the USGS in 2022 as a part of the Geologic Framework of the Intermountain West project in Denver, Colorado. His interdisciplinary research involves collaborations among structural geologists and geophysicists to study how seismic waves interact with structural features such as faults, shear zones, plutons, and foliated rocks from Earth’s surface to the deep crust. Michael’s research tools include GIS geologic mapping, microscope petrography, Electron Backscattered Diffraction, quantitative structural analysis, geophysical modeling, and boots-on-the-ground field geology.
