Bedrock Geology GIS Map of the Twin Bridges Quadrangle, Tennessee at 1:24,000 Scale

A digital bedrock geologic-GIS map of the Twin Bridges Quadrangle in Tennessee, composed of GIS data layers and tables. The dataset was completed by the National Park Service's Geologic Resources Inventory program, adapted from a 1965 Tennessee Division of Geology map. It is available in multiple GIS formats including an ESRI file geodatabase and an OGC geopackage.

Use Cases

• Conducting geologic unit analysis based on the provided bedrock geologic units and contacts.
• Creating geologic maps for the Obed Wild and Scenic River area based on the included GIS data layers.
• Assessing locational accuracy of geologic features based on the documented 12.2-meter horizontal accuracy standard.
• Integrating geologic unit descriptions into a GIS workflow using the ancillary PDF documentation.

Strengths

• Includes multiple GIS formats (ESRI file geodatabase, OGC geopackage) and supporting ArcGIS Pro and QGIS files.
• Provides ancillary documentation with geologic unit descriptions and metadata in user-friendly FAQ PDF format.
• Documents a horizontal locational accuracy of 12.2 meters based on the source map scale of 1:24,000.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Data may reflect geographic bias inherent to the specific Twin Bridges Quadrangle area.
• Last updated 2026-03-04 01:03:29.467356; freshness should be verified.

Provenance

Source

National Park Service (NPS) Geologic Resources Inventory (GRI) program, adapted from Tennessee Division of Geology source maps.

Collection Method

Digitized and adapted from a Tennessee Division of Geology Geologic Quadrangle Map by Coker (1965).

Time Range

Source map from 1965.

Freshness

Last updated 2026-03-04 01:03:29.467356.

Geography

Twin Bridges Quadrangle, Tennessee, United States.