| Title | Regional stratigraphic understanding of the Labrador-Baffin Seaway |
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| Author | Dafoe, L T ;
Williams, G L; Dickie, K; Gregersen, U; Knutz, P C; Dam, G; Pedersen, G K; Nohr-Hansen, H; Haggart, J W; DesRoches, K |
| Source | GSA 2020 Connects Online; Geological Society of America, Abstracts With Programs vol. 52, no. 6, 200-5, 2020 p. 1, https://doi.org/10.1130/abs/2020AM-355218 |
| Year | 2020 |
| Alt Series | Natural Resources Canada, Contribution Series 20200616 |
| Publisher | Geological Society of America |
| Meeting | GSA 2020 Connects Online - Geological Society of America Annual Meeting; October 26-30, 2020 |
| Document | serial |
| Lang. | English |
| Media | digital; on-line |
| File format | html; pdf |
| Province | Newfoundland and Labrador; Eastern offshore region |
| Subjects | environmental geology; general geology; geochronology; geophysics; marine geology; Nature and Environment; stratigraphy; tectonics; Lower Cretaceous; stratigraphic analyses; geophysical interpretations;
lithology; paleoenvironment; unconformities; Labrador Sea; Davis Strait; Baffin Bay Basin; Cretaceous; Cenozoic |
| Program | GEM2: Geo-mapping for Energy and Minerals Baffin Region |
| Released | 2020 10 29 |
| Abstract | The Labrador-Baffin Seaway which includes the Labrador Sea, Davis Strait, and Baffin Bay began forming during Early Cretaceous rifting between the paleo-North American and Greenland plates. Regional
geophysical and stratigraphic studies of the resultant offshore and associated onshore basins have been undertaken for decades, but our understanding of the tectonostratigraphic evolution and relationship of the two margins of the seaway is somewhat
uncertain. To resolve this, we integrated interpretations from the conjugate margins and divided the stratigraphy into Cretaceous, lower Cenozoic, and upper Cenozoic intervals, with relationships illustrated in conjugate margin profiles and
distribution maps. We correlated the lithology, ages, paleoenvironments, and unconformities and integrated seismic stratigraphic frameworks from each margin. During the Early Cretaceous, localized basins formed and were infilled with nonmarine and
shallow marine strata, succeeded by a transgressive, Upper Cretaceous marine mudstone and localized sandstone succession as rifting continued and widespread subsidence ensued. Seafloor spreading began in the central Labrador Sea in the Maastrichtian,
but propagated regionally by the Early Paleocene along with significant volcanism centered in the Davis Strait. At about the same time, regional regression took place, with a localized middle Paleocene unconformity developed along the western margin
of the seaway, but significant missing section to the east. The overlying lower Cenozoic interval is middle Paleocene to Middle Miocene and includes a period of basin inversion starting in the late Paleocene, due to strike-slip motion related to a
regional change in the seafloor spreading direction. Initial shallow marine and nonmarine strata are succeeded by a Lower Eocene transgressive phase. Spreading finally ceased in the Late Eocene, but the top of the lower Cenozoic interval is marked by
missing section at the base of major clinothems developed within the upper Cenozoic interval. Progradation during this latest interval built parts of the shelf and blanketed the deep water. Our regional correlations help to construct a more complete
understanding of the tectonostratigraphic evolution of the region, as well as highlight margin-specific and localized events. |
| Summary | (Plain Language Summary, not published)
This work outlines the integrated stratigraphic framework for the Labrador Sea, Davis Strait and Baffin Bay region, which is related to the opening of
the ocean and related sedimentary basins. Basins are infilled with primarily sedimentary rocks as old as Lower Cretaceous, with the youngest rocks of Cenozoic age blanketing much of the seafloor. Both offshore and localized onshore basins were
integrated in terms of the stratigraphy and seismic framework to provide regional comparisons and an improved understanding of the tectonostratigraphic history. Seismic sections and distribution maps are used to illustrate these
relationships. |
| GEOSCAN ID | 327880 |
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