Cretaceous Strata on the Baffin Island Shelf

Brian MacLean¹, Graham Williams¹, and Shunxin Zhang^2
1Natural Resources Canada, Geological Survey of Canada, Atlantic, Dartmouth, NS, Canada.
²Canada-Nunavut Geosience Office, Iqaluit, NU, Canada.

Extensive investigations of the surface and near surface bedrock of the Baffin Island continental shelf have been conducted by the Geological Survey of Canada using shallow and high resolution seismic systems and by borehole drilling using an underwater electric drill with 10 m seabed penetration capability. Early studies revealed the presence of rocks that included Precambrian gneisses and Ordovician limestones on the Southeast Baffin Shelf and volcanics in mid-Davis Strait, but most important from a regional petroleum perspective, Cretaceous (Albian - Cenomanian) organic rich mudstones and siltstones were found to occur in Cumberland Sound, and Upper Cretaceous mudstones on the Northeast Baffin Shelf. New palynological studies, based on more sophisticated sample processing and comparison of assemblages with those from Bylot Island sections and from Greenland wells, now give us more precise age control on these samples. The cores of Upper Cretaceous mudstones from Home Bay and Buchan Gulf and from Upper Cretaceous black shale at the oil seep locality offshore Scott Inlet range in age from Turonian to Campanian. The presence of these strata at these widely separated localities is indicative of their widespread occurrence in the subsurface of the Northeast Baffin Shelf. A sample of sandstone of Albian - Cenomanian age suggests that Cretaceous strata are involved in northeastward trending diapiric ridge structures on the Southeast Baffin Shelf seaward from Cumberland Sound. Geophysical data suggest these structures were formed by intrusion of volcanic material at depth as rifting occurred during the Tertiary. We are now integrating results of the new biostratigraphic data with the results of 2010 maturation studies of samples from the cores.

 

AAPG Search and Discovery Article #90130©2011 3P Arctic, The Polar Petroleum Potential Conference & Exhibition, Halifax, Nova Scotia, Canada, 30 August-2 September, 2011.

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