The upper Paleozoic regional development of the Ottar basin from seismic 2D interpretation

Abstract

The Ottar basin is not yet formally defined, but is a known structural element situated under the Bjarmeland Platform in the southwestern Barents Sea, buried beneath thick, flay-lying Mesozoic strata. This thesis focuses on delineating the informal upper Paleozoic Ottar basin. The delineation presented, is based on lateral/vertical variations in lithology and the surrounding tectonic setting of the Ottar basin. Several 2D seismic surveys were utilized and interpreted for this task, with the aid of well-ties from two wells penetrating the upper Paleozoic succession (7226/11-1 and 7124/3-1) located at the Norsel High and the Nysleppen Fault Complex, in close proximity to the Ottar basin.

The study includes three seismic units encompassing four different lithostratigraphic units of the upper Paleozoic succession (Billefjorden-, Gipsdalen-, Bjarmeland- and Tempelfjorden- Groups). An enclosed delineation and a geological development model of the Ottar basin has been proposed.