Skip to Main Content
Book Chapter

Late Quaternary Sea-Level Changes in Maine

By
Daniel F. Belknap
Daniel F. Belknap
Department of Geological Sciences and Center for Marine Studies, University of Maine, Orono, ME 04469
Search for other works by this author on:
Bjorn G. Andersen
Bjorn G. Andersen
Institute for Quaternary Studies, University of Maine, Orono, ME 04469
Search for other works by this author on:
R. Scott Anderson
R. Scott Anderson
Department of Botany, University of Maine, Orono, ME 04469
Search for other works by this author on:
Walter A. Anderson
Walter A. Anderson
Maine Geological Survey, State House Station 22, Augusta, ME 04333
Search for other works by this author on:
Harold W. Borns, JR.
Harold W. Borns, JR.
Department of Geological Sciences and Institute for Quaternary Studies, University of Maine, Orono, ME 04469
Search for other works by this author on:
George L. Jacobson
George L. Jacobson
Department of Botany and Institute for Quaternary Studies, University of Maine, Orono, ME 04469
Search for other works by this author on:
Joseph T. Kelley
Joseph T. Kelley
Department of Geological Sciences and Institute for Quaternary Studies, University of Maine, Orono, ME 04469 and Maine Geological Survey, State House Station 22, Augusta, ME 04333
Search for other works by this author on:
R. Craig Shipp
R. Craig Shipp
Center for Marine Studies, University of Maine, Orono, ME 04469
Search for other works by this author on:
David C. Smith
David C. Smith
Department of History and Institute for Quaternary Studies, University of Maine, Orono, ME 04469
Search for other works by this author on:
Robert Stuckenrath, JR
Robert Stuckenrath, JR
Radiocarbon Laboratory and Smithsonian Environmental Research Center, Rockville, MD 20852-1773
Search for other works by this author on:
Woodrow B. Thompson
Woodrow B. Thompson
Maine Geological Survey, State House Station 22, Augusta, ME 04333
Search for other works by this author on:
David A. Tyler
David A. Tyler
Department of Civil Engineering, University of Maine, Orono, ME 04469
Search for other works by this author on:
Published:
January 01, 1987

Abstract:

On the Maine coast, evidence of local relative sea level 12.5 ka is now exposed 60-80 m above present sea level. At that time, eustatic sea level was at least 70 m below present in most parts of the world. The difference is due to isostatic depression of the Maine coast by the weight of glacial ice. During deglaciation, the sea advanced inland in contact with the retreating margin of the marine-based ice sheet. Due to isostatic rebound and the contours of the land, the ice sheet grounded as much as 150 km inland of the present coast, glaciomarine deltas formed, and the transgression reached a stillstand at what is termed the upper marine limit. Due to differential tilting during rebound, this marine limit is now over 132 m in elevation at its farthest inlet extent. As rebound became dominant, sea level reached to 65 m below present at about 9.5 ka. At that time rebound slowed to about the same rate as that of eustatic sea-level rise. Shorelines were cut and deltas were formed at this lower marine stillstand position. Subsequently, eustatic rise became the predominant mode. Radiocarbon dates on fossil marine mollusks provide timing for this onlap and offlap.

From 7.0 ka to the present, radiocarbon dates on wood and salt marsh peats provide a relatively precise sea-level curve. During the period 4.2--1.5 ka, sea level rose at 1.22 m/1,000 yrs. Before that period, it may have risen more than twice as fast. After 1.5 ka, it slowed to half the mid-late Holocene rate. Recent tide-gauge records show an acceleration in rate to 2--3 mm/yr for the past 40 yrs. Releveling, tide gauges, and other evidence (Anderson and others, 1984) suggest that the coast is being warped downward to the east, possibly due to non-glacially induced neotectonics.

You do not currently have access to this article.

Figures & Tables

Contents

SEPM Special Publication

Sea-Level Fluctuation and Coastal Evolution

Dag Nummedal
Dag Nummedal
Department of Geology and Geophysics Louisiana State University, Baton Rouge, Louisiana
Search for other works by this author on:
Orrin H. Pilkey
Orrin H. Pilkey
Department of Geology Duke University, Durham, North Carolina
Search for other works by this author on:
James D. Howard
James D. Howard
Skidaway Institute of Oceanography Savannah, Georgia
Search for other works by this author on:
SEPM Society for Sedimentary Geology
Volume
41
ISBN electronic:
9781565760950
Publication date:
January 01, 1987

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal