A natural transect of the Tertiary fold-and-thrust belt along Spitsbergen's west coast is exposed on Midterhuken peninsula. The deformation involves two main geologic sequences. Basement rocks on Midterhuken's western tip (Hecla Hoek sequence) were metamorphosed and penetratively deformed during the Caledonian orongeny, and were uplifted and tilted during Tertiary deformation. To the east is a Lower Carboniferous to Cretaceous plaatform cover sequence (2 km thick) of unmetamorphosed carbonate and clastic rocks; it unconformably overlies the Hecla Hoek rocks, and forms a northeast-dipping homocline with locally complex structures. Except for one significant structural repetition of beds, successively younger stratigraphic units are exposed eastward. Tertiary tectonism occurred as the Barents Shelf moved dextrally past northeast Greenland on a transform fault linking spreading in the Arctic and Norwegian-Greenland Seas. The transcurrent plate setting and the compression nature of Tertiary deformation along Spitsbergen's west coast are reconciled by postulating that transpression (combined strike-slip and convergent plate movement) was decoupled. The strike-slip movement is largely concealed offshore and the lateral compression is exposed onshore.
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- Structural Properties (Geology);
- Geological Faults;
- Gravitational Effects;