Evidence for Eurekan deformation within and around the Morris Jesup Plateau, Arctic Ocean

The Morris Jesup Plateau is located offshore North Greenland and includes the Morris Jesup Rise in the west and the Morris Jesup Spur in the east. The Yermak Plateau north of Svalbard represents the conjugate margin of the Morris Jesup Plateau. Both margins are separated by the southernmost part of the Eurasia Basin with the Gakkel Ridge. The wider Eurasia Basin started to open in Paleocene-Eocene times. At those times, Greenland moved northwards due to active spreading both in the NE Atlantic and the Labrador Sea. This northward motion of Greenland resulted in the Eurekan compressional deformation between Greenland and Svalbard and limited or strongly influenced the opening of the Eurasia Basin towards the southwest. Only with the cessation of the Eurekan deformation in late Eocene times, the spreading system of the Eurasia Basin advanced southwards and finally separated the Yermak and Morris Jesup plateaus.While Eurekan deformation is well documented onshore across the West Spitsbergen Fold-and-Thrust Belt and complex thrust and strike-slip zones in North and NE Greenland, only little is known about how these compressional/transpressional structures continue offshore across the North Greenland continental margin towards the Morris Jesup Plateau. Furthermore, the extent to which the Morris Jesup Plateau was affected by extension prior to its separation from the Yermak Plateau in the early Oligocene is poorly resolved. Answering these questions is essential to determine where the Morris Jesup and Yermak plateaus were situated along the North American margin in the late Mesozoic and earliest Cenozoic. Was the opening of the Eurasia Basin compensated by deformation within the plateaus, or did strike-slip movements reactivate the ancient Paleozoic Canadian Arctic transform system? Are there any indications for initial subduction to the North of Greenland as previously proposed on base of potential field data?Here we report on the first multichannel seismic survey along with magnetic data of the southern Morris Jesup Plateau. The seismic data image transpressional and transtensional deformation likely associated with the two Eurekan deformation episodes, the transition to passive margin evolution as well as glacial sedimentation. We compare the results with two seismic lines of the northern Morris Jesup Plateau, which allow to discuss structural variations along the Morris Jesup Spur.