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Title: A buried marine depositional sequence (Presumpscot FM. ) N. of the marine limit, Waterboro, Maine

Subsurface investigations conducted in Waterboro, ME (York Co.) in connection with studies of two hazardous waste sites and a municipal water supply exploration project, have demonstrated that a laterally extensive sequence of marine deposits underlies surficial sediments mapped as non-esker ice contact glacio-fluvial deposits. The marine deposits consist of a fining-downwards sequence of grey, micaceous sands (fine to medium, grading down to a silty-fine sand), which grade downward into a thick ([plus minus] 30 feet) grey silt/clay unit, which itself shows a fining-downward trend. The stratigraphy is likely correlative to the Presumpscot Formation, as described by Bloom (1963). The bottom of the regressive marine sequence is marked at several locations by a thin layer of sand-sized biotite mica. Lodgement till was encountered only at scattered localities (in boreholes) at each site. The bedrock surface is of considerable relief, with changes of 200--300 feet over short distances detected. The sequence appears to be the record of a rapidly transgressing sea which inundated a valley where outwash had been deposited by meltwater ahead of retreating ice. As the sea retreated, up to 70 feet of sediment was deposited in a continuous, coarsening-upwards sequence. Subsequent to the marine regression, the sediments were reworkedmore » in a subaerial (braided stream) environment. The Surficial Geologic Map of Maine shows that the inland limit of late-glacial marine submergence is located approximately 8 miles southwest of Waterboro, in Alfred, Maine. The marine limit in Alfred takes the form of a NNE trending, blunt-ended embayment. The results of this study suggest that the marine embayment once extended northward from Alfred, and is now a buried feature, possibly representing a preglacial valley, which hosted an estuary in late Wisconsonian time.« less
Authors:
 [1]
  1. (Caswell, Elchler and Hill, Inc., Portsmouth, NH (United States))
Publication Date:
OSTI Identifier:
5504777
Report Number(s):
CONF-9303211--
Journal ID: ISSN 0016-7592; CODEN: GAAPBC
Resource Type:
Conference
Resource Relation:
Journal Name: Geological Society of America, Abstracts with Programs; (United States); Journal Volume: 25:2; Conference: 28. annual Geological Society of America (GSA) Northeastern Section meeting, Burlington, VT (United States), 22-24 Mar 1993
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; 54 ENVIRONMENTAL SCIENCES; GEOLOGIC FORMATIONS; DEPOSITION; STRATIGRAPHY; MAINE; ALLUVIAL DEPOSITS; CLAYS; GEOLOGY; HAZARDOUS MATERIALS; MAPPING; MORAINES; SAND; SITE CHARACTERIZATION; SPATIAL DISTRIBUTION; DEVELOPED COUNTRIES; DISTRIBUTION; GEOLOGIC DEPOSITS; MATERIALS; NORTH AMERICA; USA 580000* -- Geosciences; 540250 -- Environment, Terrestrial-- Site Resource & Use Studies-- (1990-)