Location and area. The territory covered in this report is a roughly rectangular area of about fifty square miles. It is situated partly in Marlboro and partly in Brattleboro township, in Windham county, southeastern Vermont. It runs from 42° 50' to 42° 55' north latitude and from 72° 37' to 72° 47' west longitude. Geologically the region is a part of the Green Mountains while physiographically the area is in the New England Upland section.
Statement of the Problem and Methods. The origin, history and correlation of the country rock of the region is the particular problem with which this thesis is concerned. Some attention has been directed toward the physiographic problems and the economic resources of this section of Vermont.
During the summer of 1930, the Oberlin Geologic Survey spent seven weeks in Marlboro township, Vermont. Hand specimens of the various rock types were collected, and the field relations of the formations were studied. Following the return from the field, about a hundred thin sections made from hand specimens were examined with the petrographic microscope, and a qualitative chemical analysis was made from a few of the more important minerals. The aim of this thesis is state and to interpret the results obtained from these lines of investigation.