Romoland Quadrangle Geologic Map with Lithology and Age Data

USGS provides a digital geologic map database for the Romoland 7.5' quadrangle in Riverside County, California. The dataset includes ARC/INFO coverages, a Postscript plot file with a topographic base, and PDF documentation. Map units are identified by formationname, age, and lithology, with grain size indicated by subscripted letters.

Use Cases

• Classify landform types using map unit symbols and lithology descriptors like 'Qyfa' for young alluvial fan deposits.
• Analyze spatial distribution of geologic ages and formations across the quadrangle.
• Model sediment composition by parsing grain size indicators (e.g., 'a' for arenaceous, 's' for silt) within unit symbols.
• Create derivative maps by overlaying geologic units from the ARC/INFO coverages onto topographic bases.

Strengths

• Includes a Correlation of Map Units (CMU) and Description of Map Units (DMU) diagram for interpretation.
• Map units are defined by multiple standard geologic criteria: formationname, age, and lithology.

Limitations

• Test plots have not produced precise 1:24,000-scale map sheets, affecting cartographic accuracy.
• The Correlation of Map Units is in USGS editorial format but has not been edited to comply with full I-map standards.
• Specific quantitative metrics like row count, file size, and temporal coverage are unknown.

Provenance

Source

CEOS_EXTRA, likely originating from USGS (United States Geological Survey) based on format description.

Collection Method

Digital compilation and creation of ARC/INFO coverages and graphic files from geologic mapping.

Time Range

null

Freshness

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Geography

Romoland 7.5' quadrangle, Riverside County, California.