Skip to Main Content
Book Chapter

A ground penetrating radar investigation of a glacial-marine ice-contact delta, Pineo Ridge, eastern coastal Maine

By
Anna K. Tary
Anna K. Tary
1
Department of Natural Sciences, Bentley College, Waltham, Massachusetts 02452, USA
Search for other works by this author on:
Duncan M. FitzGerald
Duncan M. FitzGerald
2
Department of Earth Sciences, Boston University, Boston, Massachusetts 02215, USA
Search for other works by this author on:
Thomas K. Weddle
Thomas K. Weddle
3
Maine Geological Survey, State House Station 22, Augusta, Maine 04333, USA
Search for other works by this author on:
Published:
January 01, 2007

In eastern coastal Maine, many flat-topped landforms, often identified as glacial-marine deltas, are cultivated for blueberry production. These agriculturally valuable features are not exploited for aggregate resources, severely limiting stratigraphic exposure. Coring is often forbidden; where permissible, coarse-grained surficial sediments make coring and sediment retrieval difficult.

Ground penetrating radar (GPR) has become an invaluable tool in an ongoing study of the otherwise inaccessible subsurface morphology in this region and provides a means of detailing the large-scale sedimentary structures comprising these features. GPR studies allow us to reassess previous depositional interpretations and to develop alternative developmental models.

The work presented here focuses on Pineo Ridge, a large, flat-topped ice-marginal glacial-marine delta complex with a strong linear trend and two distinct landform zones, informally termed East Pineo and West Pineo. Previous workers have described each zone separately due to local morphological variation. Our GPR work further substantiates this geomorphic differentiation. East Pineo developed as a series of deltaic lobes prograding southward from an ice-contact margin during the local marine highstand. GPR data do not suggest postdepositional modification by ice-margin re-advance. We suggest that West Pineo has a more complex, two-stage depositional history. The southern section of the feature consists of southward-prograding deltaic lobes deposited during retreat of the Laurentide ice margin, with later erosional modification during marine regression. The northern section of West Pineo formed as a series of northward-prograding deltaic lobes as sediment-laden meltwater may have been diverted by the existing deposits of the southern section of West Pineo.

You do not currently have access to this article.

Figures & Tables

Contents

GSA Special Papers

Stratigraphic Analyses Using GPR

Gregory S. Baker
Gregory S. Baker
Search for other works by this author on:
Harry M. Jol
Harry M. Jol
Search for other works by this author on:
Geological Society of America
Volume
432
ISBN print:
9780813724324
Publication date:
January 01, 2007

References

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal