Basin Research: Architecture of the evaporite accumulation and salt structures dynamics in Tiddlybanken Basin, southeastern Norwegian Barents Sea

Muhammad Hassaan, Jan Inge Faleide, Roy Helge Gabrielsen (all UiO) and Filippos Tsikalas (Vår Energi, UiO) are the authors of the article “Architecture of the evaporite accumulation and salt structures dynamics in Tiddlybanken Basin, southeastern Norwegian Barents Sea”. A preprint of the article has recently been published in the journal Basin Research.

Abstract

An extensive, reprocessed 2D seismic dataset was utilized together with available well data to study the Tiddlybanken Basin in the southeastern Norwegian Barents Sea, which is revealed to be an excellent example of base salt rift structures, evaporite accumulations and evolution of salt structures. Late Devonian-early Carboniferous NE-SW regional extensional stress affected the study area and gave rise to three half-grabens that are separated by a NW-SE to NNW-SSE trending horst and an affiliated interference transfer zone. The arcuate nature of the horst is believed to be the effect of pre-existing Timanian basement grain, while the interference zone formed due to the combined effect of a Timanian (basement) lineament and the geometrical arrangement of the opposing master faults. The interference transfer zone acted as a physical barrier, controlling the facies distribution and sedimentary thickness of three layered evaporitic sequences. During the late Triassic, the northwestern part of a salt wall was developed due to passive diapirism and its evolution was influenced by halite lithology between the three layered evaporitic sequences. The central and southeastern parts of the salt wall did not progress beyond the pedestal stage due to lack of halite in the deepest evaporitic sequence. During the Triassic-Jurassic transition, far-field stresses from the Novaya-Zemlya fold-and-thrust belt reactivated the pre-salt Carboniferous rift structures. The reactivation led to the development of the Signalhorn Dome, rejuvenated the northwestern part of the salt wall, and affected the sedimentation rates in the southeastern broad basin. The salt wall together with the Signalhorn Dome and the Carboniferous pre-salt structures were again reactivated during post-Early Cretaceous, in response to regional compressional stresses. During this main tectonic inversion phase, the northwestern and southeastern parts of the salt wall were rejuvenated; however, salt reactivation was minimized towards the interference transfer zone beneath the center of the salt wall.

Key words: Barents Sea, pre-salt rift geometries, layered evaporitic sequences, salt structures, evaporite dynamics, halokinetic sequences, tectonic inversion

Reference: 

Hassaan, M.; Faleide, J.I.; Gabrielsen, R.H; Tsikalas, F. (2020): Architecture of the evaporite accumulation and salt structures dynamics in Tiddlybanken Basin, southeastern Norwegian Barents Sea. Basin Research, 2020;00:1–27. DOI: 10.1111/bre.12456. [intranet]