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Plate reorganization: a cause of rapid late Neogene subsidence and sedimentation around the North Atlantic?

S. CLOETINGH, F. M. GRADSTEIN, H. KOOI, A. C. GRANT and M. KAMINSKI
Journal of the Geological Society, 147, 495-506, 1 May 1990, https://doi.org/10.1144/gsjgs.147.3.0495
S. CLOETINGH
1Institute of Earth Sciences, Free University, PO Box 716, 1007 MC Amsterdam, The Netherlands
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F. M. GRADSTEIN
2Atlantic Geoscience Centre, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada
3Geology Department, Dalhousie University, Halifax, Nova Scotia, Canada
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H. KOOI
1Institute of Earth Sciences, Free University, PO Box 716, 1007 MC Amsterdam, The Netherlands
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A. C. GRANT
2Atlantic Geoscience Centre, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada
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M. KAMINSKI
3Geology Department, Dalhousie University, Halifax, Nova Scotia, Canada
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Abstract

Subsidence analysis of wells in the central North Sea and Labrador-Grand Banks and oft the West Greenland, Scotian shelf and United States Atlantic margin shows distinct quantitative stratigraphic correlation patterns of circum North Atlantic sites. A significant departure from the overall decrease in subsidence for the Pliocene occurs in many wells, when the rate is found to have increased one or more orders of magnitude from Oligocence/Miocene rates. Wells were selected along transects from shore to basin to find if relative basin position is influenced by differential basin subsidence. Although stratigraphic resolution is not detailed, more basinward sites experienced up to four times larger subsidence rates in the late Neogene than in the Oligocene/Miocene, with a peak in the Pliocene. Wells at the basin edge experienced much less subsidence or showed uplift. The observations are consistent with a rapid change of intraplate stress at the cause for this observed transition in Neogene subsidence. Major reorganizations of spreading direction and rate occurred during the Pliocene along the entire Atlantic spreading system, possibly in conjunction with more global changes in plate motions. We propose that the associated changes in intraplate stress caused the excess margin subsidence. Relative uplift along basin edges is consistent with this mechanism of relative movement and may explain apparent eustatic changes in sea level.

  • © Geological Society of London 1990

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Journal of the Geological Society: 147 (3)
Journal of the Geological Society
Volume 147, Issue 3
May 1990
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Plate reorganization: a cause of rapid late Neogene subsidence and sedimentation around the North Atlantic?

S. CLOETINGH, F. M. GRADSTEIN, H. KOOI, A. C. GRANT and M. KAMINSKI
Journal of the Geological Society, 147, 495-506, 1 May 1990, https://doi.org/10.1144/gsjgs.147.3.0495
S. CLOETINGH
1Institute of Earth Sciences, Free University, PO Box 716, 1007 MC Amsterdam, The Netherlands
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F. M. GRADSTEIN
2Atlantic Geoscience Centre, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada
3Geology Department, Dalhousie University, Halifax, Nova Scotia, Canada
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H. KOOI
1Institute of Earth Sciences, Free University, PO Box 716, 1007 MC Amsterdam, The Netherlands
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A. C. GRANT
2Atlantic Geoscience Centre, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada
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M. KAMINSKI
3Geology Department, Dalhousie University, Halifax, Nova Scotia, Canada
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Plate reorganization: a cause of rapid late Neogene subsidence and sedimentation around the North Atlantic?

S. CLOETINGH, F. M. GRADSTEIN, H. KOOI, A. C. GRANT and M. KAMINSKI
Journal of the Geological Society, 147, 495-506, 1 May 1990, https://doi.org/10.1144/gsjgs.147.3.0495
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