Coaxial Stretching or Lithospheric Simple Shear in the North Sea? Evidence from Deep Seismic Profiling and Subsidence
Published:January 01, 1989
Simon L. Klemperer, Nicky White, 1989. "Coaxial Stretching or Lithospheric Simple Shear in the North Sea? Evidence from Deep Seismic Profiling and Subsidence", Extensional Tectonics and Stratigraphy of the North Atlantic Margins, A. J. Tankard, H. R. Balkwill
Download citation file:
The mechanism of lithospheric extension within the North Sea rift system is a matter of considerable controversy: did the basin form by coaxial stretching of the crust and lithospheric mantle (pure shear) or by lithospheric simple shear? Interpretations of deep seismic-reflection profiling have been used to support lithospheric simple shear, using as evidence basin polarity, crustal reflectors possibly from shear zones, and asymmetry of mantle reflectors. We believe that all this evidence is equivocal and may equally support coaxial stretching. A recently released deep seismic profile across the Central graben is used to illustrate the possible tectonic models and to demonstrate that the deep reflection data are also consistent with a stretching (pure shear) model. The results of numerical modeling indicate that the lithospheric simple-shear model and other noncoaxial extension models fail to account for the observed distribution of subsidence in the North Sea, which is best explained by coaxial stretching.
Figures & Tables
Extensional Tectonics and Stratigraphy of the North Atlantic Margins
Stimulated by the wealth of frontier exploration data and deep seismic surveys about the North Atlantic margins, this publication was crafted to provide a comprehensive analysis of North Atlantic extension. The 40 papers in this volume are divided into 6 sections: concepts, North Atlantic perspectives, North American margins, European-African margins, North Sea and Barents Shelf, and analogs. This book is concerned primarily with the circum-North Atlantic data base. It is largely biased toward presentation and interpretation of data rather than being model driven. The book includes comparative stratigraphic columns for basins of the North Atlantic margins.