Mid to Late Cenozoic Development of Baffin Bay - Northwest Greenland Margin

Paul Knutz, John R. Hopper, and Ulrik Gregersen
Geophysics, GEUS, Copenhagen, Denmark.

We present results from recent seismic mapping performed by GEUS in the Baffin Bay region, with focus on the mid-late Cenozoic basin development. Seismic interpretation, principally using TGS 2D lines collected 2007-2009, demonstrates an upper strata package composed of 5 major units (A-E) and numerous sub-units. A chronological framework for the seismic stratigraphy is proposed, based on a tie between ODP 645 and TGS data collected in Canadian waters. The unit geometries, bounding unconformities and internal seismic facies are interpreted with respect to tectonic, oceanographic and climatic development in the region.

The Baffin Bay fan represents a major depocentre, extending from the Nares Strait southward into the deep basin. The early progression of this fan complex, from Paleocene?-early Eocene and presumably into early Oligocene (units E-D), is linked to the Eurekan Orogeny in Ellesmere Island and the Nares Strait. A system of channelized deposits and distal fan units, is interpreted as the sedimentary response to the tectonic culmination of the Greenland-North American collision. The Baffin Bay fan complex continues to evolve in successive stages of progradation and aggradation into the late Neogene and Quaternary (units C-A), suggesting major changes in relative sea-level.

During the early Neogene, hemipelagic marine shales infilled the Melville Bay inversion grabens (unit D). This regime is terminated at the Mid-Miocene boundary and replaced by mass-flow dominated deposition in the deep basin and build-up of contourite drifts over and along the Greenland shelf margin (unit C-B). The final development phase (unit A) is manifest by shelf progradation and construction of glacigenic trough-mouth fans, extending basinward into thick debrite units, that demarcate the seaward expansion of the Greenland Ice Sheet. Unconformable strata boundaries, indicative of rapid base level adjustments, are tentatively correlated with evidence of continental uplift in West Greenland.

 

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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