Analysis of fault populations in western Spitsbergen: implications for deformation partitioning along transform margins

Mesoscale faults are used to define the history of continental deformation associated with the development of the transform system that accompanied the opening of the Eurasian basin and the Norwegian-Greenland Sea. A fundamental change in the orientation of faults from dominantly north-south in the basal part of the basin to northeast striking in the upper units broadly correlates with a major shift in plate motion during the late Palaeocene-early Eocene time. The two main populations of faults are interpreted as extension fractures that were variably reactivated as shear fractures and formed in response to north-south compression followed by northeast-southwest compression. This study offers documentation of deformation partitioning during the evolution of a transform margin. -from Authors