Structural analysis of the Knølegga Fault Complex, NW Barents Sea

• Main Author: Ur-Rehman, Attiq
• Other Authors: Prof. Roy Helge Gabrielsen, Prof. Jan Inge Faleide, Dr. Michael Heeremans
• Format: Master Thesis
• Language: English
• Published: 2012
• Subjects: VDP::450; Barents Sea; Greenland; Greenland Sea
• Online Access: http://hdl.handle.net/10852/12646; http://urn.nb.no/URN:NBN:no-31953

Structural analysis of the Knølegga Fault Complex has been done using 2D seismic reflection data set in order to understand the fault geometries, fault associated features, fault segmentation and temporal evolution of the study area. The boundary faults of the Knølegga Fault Complex comprises of the three softly-linked fault segments named as F-B, F1-b and F1c. The fault segments F-B and F1-b are ‘overlapping-synthetic’ fault segments while F1-b and F1-c are ‘approaching-synthetic’ fault segments. All three master faults have down-to-the west displacement. The displacement is transferred within the master faults; hence the master faults F-B, F1-b and F1-c represent the relay zones. The sole of the master faults is deeper than the Cenozoic sediments, which is in agreement with the observations made by previous authors. The master faults are placed in the category of ‘First-Class’ following Gabrielsen (1984). The maximum displacement is observed in the central master fault segment F1-b. The displacement decreases to the north and to the south of the key line E. The structural analysis revealed that the Knølegga Fault Complex lies in a tectonic setting which has undergone both extension and contraction. The prominent structures identified are the rotated fault blocks, growth faults and staircase normal fault geometries. The contractional structures within the study area are synclines and anticline. The major rifting event in the study area is related to break-up of the Norwegian-Greenland Sea in the early Eocene. The growth fault and minor faulting within the Oligocene sediments indicate the tectonic activity during the Oligocene. The contractional structures present in the study area seem to be the result of compression in the Oligocene?-Miocene in the direction of NW-SE to WNW-ESE. The compressional stresses have deformed both the hanging wall and the footwall. This contraction is older than the Pliocene-Pleistocene glacial sediments as no contractional structures are observed in the younger Pliocene-Pleistocene sediments in the study area.