Seafloor expression and shallow structure of a fold-and-thrust system, Isfjorden, west Spitsbergen

Seafloor expression and shallow structure of a fold-and-thrust system, Isfjorden, west Spitsbergen

Blog Article

A detailed map of the structure of the west Spitsbergen fold-and-thrust belt in the Isfjorden area, Spitsbergen, is presented.The map was constructed from a dense grid of two-dimensional multichannel reflection seismic and bathymetric data.Joint interpretation of two data sets allowed a comparison of tectonic structures detected along the uppermost parts of 30x24x24 wall cabinet the seismic sections and those reflected in the morphology of the seafloor.

Three major, predominantly north-west–south-east striking faults were identified.The westernmost fault (T1) is a hinterland-directed (most likely out of sequence) thrust, while the central and easternmost faults (T2 and T3) are foreland-directed (in-sequence thrusts).The thrusts divide Isfjorden into three subareas.

Subarea 1 is bounded by thrust faults T1 and T2 and comprises Tertiary rocks surrounded by Jurassic–Cretaceous strata.The structural signature of Subarea 1 is that of a system of hinterland- and foreland-directed thrust faults, resulting in a seafloor relief characterized by parallel ridges and troughs.Subarea 2 is limited by thrust faults T2 and T3 and shows Jurassic–Cretaceous outcrops on the seafloor.

Subarea 3 is situated merrick backcountry wet cat food east of the main thrust fault T3 and mainly involves outcrops of Triassic–Jurassic rocks.Together, Subareas 2 and 3 are dominated by foreland-directed, north-west–south-east and NNW–SSE-striking thrusts that are hardly detectable in bathymetric data.