Abstract
The Tiddlybanken Basin in the southeastern Norwegian Barents Sea is an excellent example of a salt-influenced rift basin, salt structure evolution, and rim-syncline stratigraphic accumulation. Due to increased subsidence during salt withdrawal, the rim-syncline comprises thick successions of the Triassic-Middle Jurassic fluvio-deltaic basin infill. Advanced seismic attribute mapping revealed a wide range of interactions between the salt wall growth and sediment routing within the Upper Triassic-Middle Jurassic strata. The data utilized in the Tiddlybanken Basin was a conventional three-dimensional (3D) and extensive, reprocessed two-dimensional (2D) seismic data sets integrated with two new (2019) exploration wells. Late Devonian-early Carboniferous NE-SW regional extensional stress resulted in three halfgrabens in the study area, affecting the distribution of evaporite layers. The northwestern part of the salt wall was developed by passive diapirism during the late Triassic due to the availability of halite. In comparison, the central and southeastern parts did not reach further than a pedestal stage due to a lack of mobile halite. During the Triassic-Jurassic, the salt wall is recorded to have been active in three different pulses. The channel systems crossing the salt wall during late Carnian and early ?Norian indicates inactivity of the salt wall. During the Triassic-Jurassic transition, the pre-salt Carboniferous rift structures were reactivated by farfield stresses from the Novaya Zemlya fold-and-thrust belt. The reactivation led to the rejuvenation of the northwestern part of the salt wall and the development of the Signalhorn Dome. Sediment routing within the rim-syncline resulted in diversion through lateral migration and ponding due to changes in slope relief in late Norian-?Rhaetian. Erosion of the Signalhorn Dome resulted in distinct truncation patterns and an angular unconformity between Upper Triassic and the overlying Lower Jurassic strata. A local basin started to form above the southeastern and central parts of the salt wall during the lower Jurassic. Concurrently, the salt wall growth in the northwestern part was active. The entire salt wall became inactive during the middle Jurassic, resulting in a tidal-influenced depositional environment. Cenozoic compressional stresses reactivated again the Carboniferous pre-salt structures, the Signalhorn Dome, and the salt wall. The northwestern and southeastern parts of the salt wall were rejuvenated. However, the central part was insignificantly affected by the reactivation. The widespread inversion throughout the Norwegian Barents Sea resulted in regional uplift and erosion, stripping off most of the folded roof of the Tiddlybanken Basin and Signalhorn Dome.