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dc.contributor.authorBrothers, Laura L.  Concept link
dc.contributor.authorKelley, Joseph T.  Concept link
dc.contributor.authorBelknap, Daniel F.  Concept link
dc.contributor.authorBarnhardt, Walter A.  Concept link
dc.contributor.authorAndrews, Brian D.  Concept link
dc.contributor.authorLegere, Christine  Concept link
dc.contributor.authorHughes Clarke, John E.  Concept link
dc.date.accessioned2013-02-06T20:35:59Z
dc.date.available2013-02-06T20:35:59Z
dc.date.issued2012-09-27
dc.identifier.citationMarine Geology 329-331 (2012): 34-45en_US
dc.identifier.urihttps://hdl.handle.net/1912/5759
dc.descriptionThis paper is not subject to U.S. copyright. The definitive version was published in Marine Geology 329-331 (2012): 34-45, doi:10.1016/j.margeo.2012.09.006.en_US
dc.description.abstractPockmark fields occur throughout northern North American temperate estuaries despite the absence of extensive thermogenic hydrocarbon deposits typically associated with pockmarks. In such settings, the origins of the gas and triggering mechanism(s) responsible for pockmark formation are not obvious. Nor is it known why pockmarks proliferate in this region but do not occur south of the glacial terminus in eastern North America. This paper tests two hypotheses addressing these knowledge gaps: 1) the region's unique sea-level history provided a terrestrial deposit that sourced the gas responsible for pockmark formation; and 2) the region's physiography controls pockmarks distribution. This study integrates over 2500 km of high-resolution swath bathymetry, Chirp seismic reflection profiles and vibracore data acquired in three estuarine pockmark fields in the Gulf of Maine and Bay of Fundy. Vibracores sampled a hydric paleosol lacking the organic-rich upper horizons, indicating that an organic-rich terrestrial deposit was eroded prior to pockmark formation. This observation suggests that the gas, which is presumably responsible for the formation of the pockmarks, originated in Holocene estuarine sediments (loss on ignition 3.5–10%), not terrestrial deposits that were subsequently drowned and buried by mud. The 7470 pockmarks identified in this study are non-randomly clustered. Pockmark size and distribution relate to Holocene sediment thickness (r2 = 0.60), basin morphology and glacial deposits. The irregular underlying topography that dictates Holocene sediment thickness may ultimately play a more important role in temperate estuarine pockmark distribution than drowned terrestrial deposits. These results give insight into the conditions necessary for pockmark formation in nearshore coastal environments.en_US
dc.description.sponsorshipGraduate support for Brothers came from a Maine Economic Improvement Fund Dissertation Fellowship.en_US
dc.format.mimetypeapplication/pdf
dc.language.isoen_USen_US
dc.publisherElsevier B.V.en_US
dc.relation.urihttps://doi.org/10.1016/j.margeo.2012.09.006
dc.subjectPockmarksen_US
dc.subjectMethaneen_US
dc.subjectRedoximorphic featuresen_US
dc.subjectSwath bathymetryen_US
dc.subjectGulf of Maineen_US
dc.subjectBay of Fundyen_US
dc.titleShallow stratigraphic control on pockmark distribution in north temperate estuariesen_US
dc.typeArticleen_US
dc.identifier.doi10.1016/j.margeo.2012.09.006


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