Pockmarks in Passamaquoddy Bay, New Brunswick, Canada

Laura L. Brothers; Christine Legere; J.E. Hughes Clark; J.T. Kelley; Walter Barnhardt; Brian Andrews; D.F. Belknap

doi:10.1144/m46.60

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Pockmarks in Passamaquoddy Bay, New Brunswick, Canada

Laura L. Brothers·Christine Legere·J.E. Hughes Clark·J.T. Kelley·Walter Barnhardt·Brian Andrews·D.F. Belknap

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Abstract

Pockmarks are seafloor depressions associated with fluid escape ( Judd & Hovland 2007 ). They proliferate in the muddy seafloors of coastal Gulf of Maine and Bay of Fundy, where they are associated with shallow natural gas likely of biogenic origin ( Ussler et al. 2003 ; Rogers et al. 2006 ; Wildish et al. 2008 ). In North America, shallow-water pockmark fields are not reported south of Long Island Sound, despite the abundance of gassy, muddy estuaries. The absence of pockmarks south of the limit of North American glaciation suggests that local and regional heterogeneities, possibly related to glacial or sea-level history or bedrock geology, influence pockmark field distribution. In shallow-water embayments, such as Passamaquoddy Bay, New Brunswick, pockmarks can be large (>200 m diameter) and number in the thousands.

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Geological Society, London, Memoirs Article

Source-reported bounding extent: 44.91668060637917° to 45.188812246819055° latitude; -67.181396484375° to -66.86141967773438° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Laura L. Brothers, Christine Legere, J.E. Hughes Clark, J.T. Kelley, Walter Barnhardt, Brian Andrews, D.F. Belknap. 2016-11-30. Pockmarks in Passamaquoddy Bay, New Brunswick, Canada. https://doi.org/10.1144/m46.60

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