The Wilmarth Correlation Charts

Between 1925 and 1937, Grace Wilmarth (USGS) published a set of correlation charts that she prepared in order to assist in her compilation of the first Lexicon of Geologic Names of the United States (USGS Bulletin 896, 1938, see p. 4). It was Wilmarth's intention for the charts to constitute part of the published Lexicon, but this did not occur. Instead, they were informally released in limited numbers by the USGS Geologic Branch. We are pleased to make them more widely available.

To view other, and especially more recent, statewide stratigraphic charts and lexicons, please see the correlation chart site.