The Charles W. Martin collection is composed of topographic base maps, detailed geologic maps, thin sections, thin section notes, and field notes collected during Professor Martin’s years as a graduate student in the late 1950s at the University of Wisconsin-Madison and continuing through part of his career as a Professor of Geology at Earlham College. These research materials support Professor Martin’s authorship of three of the bedrock geology quadrangle maps in Connecticut: the Winsted quadrangle, the Waterbury quadrangle, and the Torrington quadrangle in addition to supporting research for the Litchfield, New Preston, and Roxbury quadrangle geologic maps.

Box 1 contains lithologic descriptions of the medium-high grade metamorphic rocks studied by Professor Martin during his graduate research along with field notes from later mapping work in the Waterbury, Winsted and Torrington quadrangles. Box 2 contains additional field notes from these areas spanning a range of time from the late 1950s to the early 1970s. Box 3 contains thin sections from Professor Martin’s graduate research (boxes with sample numbers beginning with “M”) as well as thin sections from the Waterbury, Winsted, and Torrington quadrangles along with various photomicrographs of some of these rocks. In addition, Box 3 contains a thin section collection of primarily carbonate rocks collected by Helen Hay, a professor in the Earlham College Geology Department until her death in 1995. Box 4 contains the topographic base maps used for field mapping as well as detailed hand-drawn geologic maps of Professor Martin’s research areas.

These materials comprise original research for the current bedrock geologic maps of this region. The field notes and thin sections are irreplaceable and would be helpful for any scholar wishing to see the original data upon which the geologic maps of this area in Connecticut are based. The thin sections are quite delicate, with the epoxy holding the cover slips breaking easily. However, petrographic analysis is still possible using this collection.

Written by Dr. Meg Streepey-Smith, Professor of Geology.