The role of thermal anomalies in the breakup evolution along the conjugate margins of the Fram Strait

The Eurekan Belt is an intraplate orogen that extends for nearly 2000 kilometres across the Arctic Realm and is closely linked to large-scale transform faults. After orogenic movements ceased, the Eurekan Belt became dissected, the affected margins of Greenland and the Barents Sea became passive and the Arctic-North Atlantic gateway, the Fram Strait, opened.

To obtain information on the thermal imprint of rifting and continental breakup processes along a sheared margin, we investigated highly mature sedimentary rocks exposed along both of the conjugate margins using apatite fission track and (U‐Th)/He thermochronology.

Our data suggest that a large transform fault system played a major role in the development of the Eurekan Belt and the subsequent formation of the Barents and Greenland margins: along segments of the transform fault system heating occurred prior to and during the Eurekan Orogeny. Heat transfer may have caused or contributed to lithospheric weak zones which focussed deformation during the intraplate orogeny. Movements along the transform fault system continued after the end of the Eurekan Orogeny and caused further structural weakening of pre‐existing fault zones. These were utilised during the final continental breakup leading to the opening of the Fram Strait.