The Atlantic - Arctic Connection; Kinematic Linkage of Mesozoic and Cenozoic Rifting and Rifted Margin Formation
TNE RD EXP GBA, Statoil, Oslo, Norway.
The plate kinematic evolution of the North Atlantic and Arctic oceans demonstrates tectonic and magmatic processes that are important for the petroleum prospectivity in the region. The Late Triassic to Early Cretaceous rifting in the N and NE Atlantic formed a system of spatially and temporally overlapping rift zones from the Central Atlantic to the Barents Sea. The Late Jurassic-Early Cretaceous phase of this development occurred contemporaneously with the rift to drift development of the Canada and the Makarov basins in the Arctic, and with the probable arrival of a proto Icelandic plume, causing widespread igneous activity in the Sverdrup and the Barents Sea basins (~130 Ma). When late Jurassic-Early Cretaceouis extension between Greenland and Eurasia ceased, the deformation was redirected to the Labrador Sea, reaching all the way north causing initial separation between the Lomonosov Ridge and the Barents shelf. During Labrador Sea opening renewed rifting occurred between Greenland and Eurasia, establishing a R-T-F triple junction north of Greenland to link the deformation along the Eurasia Basin Rift (R), the Eurekan Orogeny (T) and the Hornsund Transform (F), and Iceland Plume impinged beneath western Greenland, causing widespread igneous activity both in west Greenland and in the British Igneous province (63-62 Ma). As breakup eventually occurred between Greenland and Eurasia (55-54 Ma) large volumes of igneous rocks were emplaced as sills and flows along the incipient plate boundary, eventually forming the well recognized NE Atlantic volcanic margins. The R-T-F triple junction was abandoned when seafloor spreading in the Labrador system ceased (~33 Ma), causing the Hornsund transform to develop into a rifted margin allowing the opening of the Fram Strait. The opening history of the Amerasia Basin is still speculative, but new magnetic data (EMAG2; Maus et al., 2007) seem to agree with the suggestion of a bounding transform between the Makarov Basin and the Lomonosov Ridge. During the early stage development two overlapping rift zones caused the Chukchi Plateau to be rotated away both from the Canadian Arctic and the Siberian shelf (Lawver et al., 2002), eventually joining into one spreading system as the Chukchi Plateau was fully separated from the Canadian Arctic. The Alpha-Mendeleev Ridge likely represent a plume trail left by the proxy to the proto-Iceland plume, although the position of the plume centre was located beneath the Ellesmere Islands during the opening of the Makarov Basin (Lawver and Muller, 1994). Plumes at sub-lithospheric levels are presumed to cause regional uplift, and the propagating surface motion may cause significant tectonic deformation that can be recognized in areas where 3D seismic data provide the needed details. The uplift, tectonism and the associated widespread igneous activity are all factors that may significantly impact the prospectivity of a region.
AAPG Search and Discovery Article #90130©2011 3P Arctic, The Polar Petroleum Potential Conference & Exhibition, Halifax, Nova Scotia, Canada, 30 August-2 September, 2011.����������������������������������������������������������������������