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G. W. Stewart

Publications and source records attributed to G. W. Stewart.

7 recordsLinked to original sources
USGS1952

Geologic map of the Barnes Hill talc prospect, Waterbury, Vermont

The Barnes Hill talc prospect is in northeastern Waterbury township, Washington County, Vermont, about 2.2 miles N. 35° E. of the road triangle at Waterbury Center. The deposit occurs in a body of ultramafic rock that crops out between the altitudes of 1,150 and 1,190 feet above sea level, near the crest of a broad, low ridge on a gently rolling upland of low relief. The area surveyed is about 46 acres. It is drained on the east by a small tributary of Thatcher Brook and on the west by Bryant Brook. Thatcher Brook empties into the Winooski River at Waterbury; Bryant Brook flows into the Waterbury River, a tributary of the Winooski River. Most of the area is in open pasture, with a few scattered spruce and hemlock, but along the eastern side of the property there is a dense growth of maple saplings and underbrush.

Vermont↗
USGS1945

Structural and economic characteristics of New England mica deposits

In connection with the intensive wartime exploitation of domestic mica deposits, the Geological Survey has been engaged in a comprehensive investigation of New England mica pegmatites. More than 200 pegmatites have been mapped and studied in detail and some hundreds of others have been given brief examination. The opportunity for pegmatite study has been unprecedented, and much new information on the characteristics of pegmatites has been obtained. Geologic analysis of pegmatites has helped to clarify the relationships between mica distribution and structural features and has led to a classification of mica deposits into basic types, of which five are especially important: wall-zone, intermediate-zone, pod, fracture-controlled, and disseminated. In some pegmatites, designated complex deposits, combinations of two or more of the basic types have been found. The different types are described and illustrated and their relative economic importance is shown by production figures. Analyses show clearly that certain types of deposits are far more productive than others and are far more likely to sustain profitable mining operations. Applications of current studies to mica mining, prospecting, and exploration are discussed.

Connecticut, Maine, New Hampshire↗