Seismic stratigraphy and tectono-structural framework of the Bjarni area, Hopedale Basin, Labrador Sea

• Main Author: Martin, Michelle Rae
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2007
• Subjects: Newfoundland; Labrador Shelf; Okak; Hopedale; Labrador Sea; University of Newfoundland
• Online Access: https://research.library.mun.ca/6944/; https://research.library.mun.ca/6944/1/MichelleRaeMartin.pdf; https://research.library.mun.ca/6944/3/MichelleRaeMartin.pdf

The Labrador shelf and slope Mesozoic sedimentary area is divided by the Okak Arch into two large basins, the Saglek Basin and the Hopedale Basin. The Hopedale Basin is the more southerly basin and extends from the Cartwright Transfer Fault Zone (CTFZ) in the south to the Okak Arch in the North: a distance of approximately 500 kilometres from 55° to 59° latitude North. It is part of a large, oval, tectonic depression having an area of about 175 000 square kilometres. The basin has an uneven basement floor consisting of stretched continental crust, exhumed continental mantle (transitional crust) and oceanic crust. The thickest sediment accumulation is located on the outer shelf and inner slope. -- A recent seismic grid collected by Geophysical Service Incorporated (GSI) during 2003, 2004 and 2005 has produced a regional 2D seismic coverage adequately covering this vast area that contains the giant Bjarni/North Bjarni gas field. These non-exclusive seismic lines were graciously donated to Memorial University of Newfoundland to be used for regional tectonic, structural and seismic stratigraphic investigations and mapping. -- Using these donated data, several seismic sequences were defined, correlated to well information and mapped throughout the area surrounding the Bjarni/North Bjarni field. The study indicates that the Lower Cretaceous Bjarni Formation is widespread, was deposited in a large rifted area and contains the basin's main reservoir and source rock. Seismic correlations indicate that the Bjarni reservoir extends beyond the shelf and into the outer slope region. This new interpretation increases the probability that there are still many undrilled Bjarni plays on the shelf and on the slope. -- On the basis of seismic character observed on lines that extend into deepwater, it is apparent that there was a significant amount of postrift mantle exhumation on the Labrador margin expressed as serpentinized ridges as well as predrift lava flows mapped on continental and transitional crust domains. Thick syndrift ...