Oil and gas bearing in Norwegian Sea basins

Abstract

The Norwegian passive continental margin is represented by an extensive gentle shelf and continental slope. On the continental slope, there are the isolated Voring, More and Ras basins, the Halten Terrace is situated to the east of them at the shelf, then the Nordland submarine ridge and the Trondelag Platform at the seaboard. There are Paleozoic, Mesozoic and Cenozoic sediments in its sections. Two complex structures are clearly distinguished in the sedimentary section: the lower stage (up to the Upper Cretaceous), reflecting the rifting structure of the basins, broken by a system of dislocations to a series of horsts, grabens, and separated blocks; and the upper stage, poorly dislocated, like a mantle covering the lower stage, with erosion and sharp unconformity. The Halten Terrace is the principal oil and gas production basin. At present, there are more than 50 oil, gas, and condensate fields in it. The following particularities have been discovered: than the field lays in the deepwater, than the age of the hydrocarbon pay is younger. It is also interesting that all gas fields are situated in the Voring and More basins and western part of the Halten Terrace; the oil and gas fields, mainly at the center of the Halten Terrace; but pure oil fields, in the north of the terrace. In conformity with discovering the particularities, it is possible to say that the prospects of oil and gas bearing in the Norwegian Sea are primarilyt related to the Halten Terrace and the Voring and More basins, especially the territories situated at the boundary of the two basins, where it is possible to discover large hydrocarbon accumulations like the Ormen-Lange field, because the Paleocene-Upper Cretaceous productive turbidite thick at the boundary of these basins is on the continental slope, which is considered promising a priori.