Evolution of the west Greenland margin: offshore thermostratigraphic data and modelling

Abstract

The origin and age of topography along the west Greenland margin is a matter of continued debate. Evidence for tectonically driven Neogene uplift has been argued from interpretations of offshore seismic surveys, onshore fission-track data and inferred episodes of cooling. Here, analysis of seismic reflection profiles and 1D modelling of exploration wells along the Greenland margin of Davis Strait demonstrate that the data are consistent with a model of ancient continental topography affected by late Cretaceous-early Palaeocene rifting followed by thermal subsidence where offshore Neogene tectonic uplift is not required. This interpretation for the offshore evolution of the west Greenland margin has implications for the adjacent onshore evolution and for other continental margins developed throughout the Atlantic-Arctic rift system.

Tectonic variation and structural evolution of the West Greenland continental margin

“…Although, subsidence analysis of the margin reveals that Neogene uplift is unrelated to subsidence in offshore areas (McGregor et al, 2012).…”

High resolution mapping of offshore and onshore glaciogenic features in metamorphic bedrock terrain, Melville Bay, northwestern Greenland

“…One such sedimentary basin is Melville Bay graben, tens of kilometers west of the study area and characterized by a thick sedimentary section of early Cretaceous to recent age and a hydrocarbon potential comparable to the large producing fields in the North Sea (Bradbury and Woodburn, 2011;Knutsen et al, 2011;Gregersen et al, 2013). Seafloor spreading continued until the late Paleocene to create today's wide continental shelf (McGregor et al, 2012) that is between 200 and 600 m deep. The moderately sloping shelf is incised by large, cross-shelf troughs formed by massive ice streams during glacial events probably throughout the Quaternary, many of which remain unstudied (Batchelor and Dowdeswell, 2013;Ó Cofaigh et al, 2013a).…”

“…The moderately sloping shelf is incised by large, cross-shelf troughs formed by massive ice streams during glacial events probably throughout the Quaternary, many of which remain unstudied (Batchelor and Dowdeswell, 2013;Ó Cofaigh et al, 2013a). McGregor et al (2012) summarized the topography of the west Greenland margin to be the result of the varying effects of differential glacial erosion acting on the remains from the Proterozoic-Paleozoic orogenies, Mesozoic-Cenozoic rift flank formations, and in some places, magmatic intrusions along the continental margin.…”

“…Seismic studies by Knutsen et al (2011) have shown at least three uplift phases from areas close to the west Greenland coastline from the Eocene to the present, while other factors such as glacio-isostasy and ice off-loading effects could also contribute to fault reactivations. The escarpments may have been formed by tectonic rifting processes during the Cretaceous-Eocene period when extension and stretching of the continental crust occurred as a result of seafloor spreading in Baffin Bay, which eventually formed numerous coast-parallel grabens and halfgrabens, many of which are now filled with sediments (McGregor et al, 2012).…”

Basin evolution in the Davis Strait area (West Greenland and conjugate East Baffin/Labrador passive margins) from thermostratigraphic and subsidence modelling of well data: Implications for tectonic evolution and petroleum systems

“…Balkwill, 1987;Issler and Beaumont, 1987;Roest and Srivastava, 1989;Chalmers et al, 1993;Dam et al, 2000;Chalmers and Pulvertaft, 2001;Dickie et al, 2009;Gerlings et al, 2009;Keen et al, 2012;McGregor et al, 2012). Balkwill, 1987;Issler and Beaumont, 1987;Roest and Srivastava, 1989;Chalmers et al, 1993;Dam et al, 2000;Chalmers and Pulvertaft, 2001;Dickie et al, 2009;Gerlings et al, 2009;Keen et al, 2012;McGregor et al, 2012).…”