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Woodrow B. Thompson

Publications and source records attributed to Woodrow B. Thompson.

5 recordsLinked to original sources
USGS2005

Quaternary Geologic Map of Connecticut and Long Island Sound Basin

The Quaternary geologic map (sheet 1) and explanatory figures and cross sections (sheet 2) portray the geologic features formed in Connecticut during the Quaternary Period, which includes the Pleistocene (glacial) and Holocene (postglacial) Epochs. The Quaternary Period has been a time of development of many details of the landscape and of all the surficial deposits. At least twice in the late Pleistocene, continental ice sheets swept across Connecticut. Their effects are of pervasive importance to the present occupants of the land. The Quaternary geologic map illustrates the geologic history and the distribution of depositional environments during the emplacement of glacial and postglacial surficial deposits and the landforms resulting from those events.

Scientific Investigations Map↗
USGS1992

Surficial materials map of Connecticut

The unconsolidated deposits overlying bedrock in Connecticut range from a few feet to several hundred feet in thickness. These earth materials significantly affect human development of the land. Most of the unconsolidated materials are deposits of continental glaciers that covered all of New England at least twice during the Pleistocene ice age. These glacial deposits are divided into two broad categories, glacial till and glacial stratified deposits. Till, the most widespread glacial deposit, was laid down directly by glacier ice and is characterized by a nonsorted matrix of sand, silt, and clay with variable amounts of stones and large boulders. Glacial meltwater deposits are concentrated in both small and large valleys· and were laid down by glacial meltwater hi streams and lakes in front of the retreating ice margin during deglaciation. These deposits are characterized by layers of well-sorted to poorly sorted gravel, sand, silt, and clay. Postglacial sediments, primarily floodplain alluvium and swamp deposits, make up a lesser proportion of the unconsolidated materials of Connecticut. Alluvium is largely reworked from glacial materials and has similar physical characteristics.

Connecticut↗
USGS1971

The drainage and glacial history of the Still River Valley, southwestern Connecticut

The Still River is located in southwestern Connecticut. From its origin on the New York border, it passes through Danbury and flows northward to its junction with the Housatonic River in New Milford. Interpretation of the Still River's history is based on its surficial geology and bedrock topography. High bedrock surfaces to the south, east, and west of the river show that its preglacial direction was probably to the north. The Still River has developed along the easily eroded Inwood Marble as a subsequent tributary to the Housatonic. Pleistocene glaciation left a variety of deposits in the Still Valley. The oldest of these is the 'lower' till, of either Illinoian or Altonian age. This till unit is overlain in turn by the Woodfordian 'upper' till. The upper till has basal and ablation facies. Ice-contact deposits formed in the fringing stagnation zone of the last retreating ice sheet. As the glacier withdrew along the Still Valley, preglacial Lake Danbury was impounded against the highlands to the south. Glacial retreat opened progressively lower outlets for this lake. Its final stage was contained by a till (?) barrier at the Housatonic Gorge in New Milford. Filling of the lake by glacial outwash was soon followed by downcutting of the dam and establishment of the modern Housatonic and Still River channels.

Open-File Report↗