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The generation of Digital Elevation Models from stereographic pairs of aerial photographs at 1:50,000 scale and their combined analysis allowed to draw an updated geological map in the central-western part of Dicksonland forming the south-eastern termination of the N-S Devonian basin of Spitsbergen (Svalbard archipelago). From complementary field observations and analysis of microstructural data, we have precised both the structural style and the timing of deformation. We have identified three tectonic stages during the Devonian-Early Carboniferous time interval. The first one corresponds to extension during Devonian, as shown by normal faults affecting the Wood Bay formation (Early Devonian) that are sealed by the Early Carboniferous. The second stage of deformation is characterized by folding and thrusting of the Devonian sediments. Compressional deformation can be related either to compression between the Late Devonian and the Early Carboniferous or to extension during the Late Devonian. Such extension can be related to the eastward gravity sliding of soft sediments that bumped into the N-S Billefjorden fault foming the eastern boundary of the Devonian trought. The third stage of deformation corresponds to NE-SW extension during the Early Carboniferous, meaning that the rifting continued to develop after the Devonian. This late extension is responsible for transtensional motions along N-S-trending and E-W-trending faults bounding horsts and grabens. The main areas of subsidence in the southwest trapped the Early Carboniferous sediments, whose thickness progressively diminishes towards the northeast.
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