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25Stratigraphic records from northwestern Pangea provide unique insight into global processes 26 that occurred during the Latest Permian Extinction (LPE). We examined a detailed geochemical 27 record of the Festningen Section, Spitsbergen. A stepwise extinction is noted: 1) loss of 28 carbonate shelly macrofauna, 2) loss of siliceous sponges in conjunction with an abrupt change 29 in ichnofabrics as well as dramatic change in the terrestrial environment, and 3) final loss of all 30 trace fossils. We interpret loss of carbonate producers as related to higher latitude shoaling of 31 the lysocline in relationship to building atmospheric CO 2 in higher latitiudes The loss of siliceous 32 sponges is coincident the global LPE event and is related to onset of high loading rates of toxic 33 metals (Hg, As, Co) that we suggest are derived from Siberian Trap eruptions. The final 34 extinction stage is coincident with redox sensitive trace metal and other proxy data which 35 suggest onset of anoxia, after the other extinction events. These results show a remarkable 36 record of progressive environmental deterioration in NW Pangea during the extinction crises. 37

In NW Spitsbergen, the Late Silurian to Late Devonian infill of an Old Red Sandstone (ORS) basin was affected by west-vergent folding and west-directed thrusting during the Early Carboniferous (Tournaisian) Svalbardian deformation. The brittle, predominantly compressional structures of the Svalbardian Fold-and-Thrust Belt are concentrated along at least five narrow, more or less north-south-trending zones. Three zones are exposed in the Devonian infill of the ORS basin. The involvement of the post-Caledonian ?Late Silurian to Earliest Devonian Viggobreen weathering zone and deposits Early Devonian in two thrust zones within the basement of the western basin margin indicates that the Svalbardian deformation also affected the basement areas along the west coast of NW Spitsbergen. Structures of the Svalbardian Fold-and-Thrust Belt are exposed within an area at least 100 km wide between the Billefjorden Fault Zone in the east and the west coast of NW Spitsbergen. Therefore, the Svalbardian deformation represents a much more important fold belt than previously recognized. On the basis of the timing, the large extent and the orientation of the fold-and-thrust zones, the Svalbardian Fold-and-Thrust Belt appears to represent the eastern continuation of the Ellesmerian Fold Belt in North Greenland and the Canadian Arctic Archipelago.

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In NW Spitsbergen, the infill of a large Old Red Sandstone (ORS) basin was affected by the Svalbardian deformation shortly after the sedimentation of the uppermost ORS units. In the Billefjorden area, along the eastern margin of the basin, folded and thrustfaulted Devonian deposits are unconformably overlain by undeformed Carboniferous clastic sediments and platform carbonate deposits. To re-examine the age of the Svalbardian deformation, samples for palynological investigations were taken from the youngest deformed ORS strata and the oldest post-Svalbardian sediments. The results of palynological investigations show that the folded and thrust-faulted uppermost ORS unit, the Plantekløfta member of the Mimerdalen Formation (Andrée Land Group), is Late Famennian in age. The lowermost undeformed and unconformably overlying post-ORS unit, the Triungen member of the Hørbyebreen Formation (Billefjorden Group), is ?Late Tournaisian to Viséan but not Famennian in age. Thus, the compressional west-directed folding and thrusting of the Svalbardian deformation took place after Late Famennian and before Late Tournaisian time.

Besides the ∼W‐E trending Kap Cannon Thrust Zone and Harder Fjord Fault Zone, the 300 km long and NW‐SE striking Wandel Hav Mobile Belt represents the third major fault zone in north Greenland. Structural analyses in several areas of this belt suggest that compressive deformation is characterized by transpressive dextral strike‐slip kinematics. This is demonstrated by a combination of folding around ∼W‐E axes, approximately north and south directed reverse faulting, and dextral strike‐slip displacements along NW‐SE trending fault lines. The initial formation of the long, linear faults is interpreted to be related to deformational events in Late Paleozoic, Triassic‐Jurassic, and Late Cretaceous times. Due to the lack of structural evidence, we assume that deformations led to the generation of extension faults which probably were reactivated during dextral strike‐slip tectonism. It is suggested that dextral transpressive deformation was coeval with ∼N‐S compression at the Harder Fjord Fault Zone and Cap Cannon Thrust Zone and took place during Eocene (Eurekan) times. Dextral strike‐slip tectonism in the Wandel Hav Mobile Belt was the result of ∼N‐S compression due to a general northward movement of the Greenland plate. As a zone of crustal weakness, the belt can be interpreted as the onshore equivalent of the main transcurrent fault zone (De Geer Fault) which caused the intracontinental dextral slip of Svalbard (Barents Shelf) relative to north Greenland during Early Tertiary (Eurekan) times and prior to their separation. In this configuration, it represents one part of the belt of Eurekan deformation which extends from the Canadian Arctic islands over north Greenland to the Barents Shelf where compressive deformation is recorded in the West Spitsbergen Fold‐and‐Thrust Belt.