Massachusetts Geological Survey, Geologic Map, GM 13-01 Massachusetts Geological Survey Onshore-Offshore Surficial Geologic Map of the Newburyport East and University of Massachusetts, Amherst Northern Half of the Ipswich Quadrangles, Massachusetts, Sheet 3 of 3 2013 Address: 269 Morrill Science Center, 611 North Pleasant Street, Amherst, MA 01003 Phone: 413-545-4814 E-mail:
[email protected] WWW: http://www.geo.umass.edu/stategeologist Evolutionary Model Merrimack Embayment Relative Sea-Level Curve References Stage 1: Stage 2: Uncalibrated Radiocarbon Age (103 yr BP) Balco, G., Stone, J.O.H., Porter, S.C., and Caffee, M.W., 2002. Last Glacial Maximum to Glacial Sea-Level Highstand Shallow 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Cosmogenic-nuclide ages for New England coastal moraine, Martha’s Retreat 17 - 16 ka Vineyard and Cape Cod, Massachusetts, USA: Quaternary Science Reviews, v. till Deposition of 21, p. 2127-2135. ~24 - 17 ka offshore 30 Sea level rises rapidly over the isostatically Data Sources The Laurentide Ice Sheet advances through glaciomarine units Barnhardt, W., Andrews, B., Ackerman, S., Baldwin, W., and Hein, C., 2009. Laurentide depressed region as the ice margin retreats further northern Massachusetts and the Gulf of Maine, north. The maximum synglacial marine limit is High resolution geologic mapping of the inner continental shelf: Cape Ann to Salisbury Beach Massachusetts: U.S. Geological Survey Open-File Report reaching its maximum limit at Long Island (NY) Ice Sheet reached at 17–16 ka (Stone and Borns, 1986; Collins, 1989 Kaye and Barghoorn, 1964 Kirwan et al., 2011 20 McIntire and Morgan, 1964 Oldale et al., 1993 2007-1373, 50 p.