| dc.description.abstract | The area bounded between the Troms-Finnmark Fault Complex (TFFC), the Ringvassøy-Loppa Fault Complex (RLFC), the Finnmark Platform and the Tromsø and Harstad Basins is considered to be affected by high complex tectonics. 3D seismic data were used to analyze the history of the fault growth, reactivation and inversion of the major faults in the TFFC and their implications to the potential petroleum systems.
Multiple seismic attribute analysis and detailed interpretation, reveal 8 major normal dip-slip faults, forming rotated fault blocks in the TFFC. T-z and T-x profiles were used to understand the fault grow, segmentation and reactivation. Additionally, thickness maps of the seismic units and interpreted cross sections were used for the examination of possible reactivation of the major faults due to inversion.
Throw versus depth (T-z) and displacement versus distance (T-x) plots revealed complex lateral and vertical segmentation. The profiles of the plots displayed varied geometrical types, forming Skewed-M, Skewed-C, M and C-types for their segments. Some of the faults exhibit reactivation by dip linkage during Middle Jurassic Early Cretaceous. The reactivated faults exhibit polycyclic fault growth and multi modes of propagation, involving both radial and syn-sedimentary propagation. The T-x plots show that the lateral segments developed as isolated or had boundary restrictions.
The predominant mechanism of fault reactivation was due to partial positive inversion. Five faults exhibit partial positive inversion in the TFFC and therefore inversion was selective. Synclines, anticlines geometries and harpoon styles were the major features which indicate inversion in the TFFC. Inversion affected the Middle Late Triassic to Early Cretaceous sediments.
Segmentation, fault linkage and inversion have positive and negative impacts in the Lower to Middle Jurassic petroleum plays of the TFFC. Specifically, segmented faults can lead to hydrocarbon leakage and re-migration from the potential traps. The associated geometries that follow inversion can form stratigraphic traps while small reactivated fault network can lead to drainage events, destroying the sealing capacity. | en |
