Analysis of pore pressure measurements in exploration wells in the Norwegian North Sea

Abstract

The aim of this thesis was to examine the pore pressure measurements in the Norwegian North Sea. To study the possibility of the overpressure being an indicator that can increase the probability of hydrocarbon discoveries in exploration wells. Studying this hypothesis, reasons for overpressure have been elaborated. In this thesis, several wells from the northern part of the North Sea have been studied, mainly from the Tampen Area. The wells in this area are all exposed to an abnormal pore pressure. The reason for overpressure is further investigated in this paper. The overpressure has an impact on the production rate and influences the start-up time for injection or artificial lift. The effect of overpressure has been considered regarding production. It was found that the water pressure below the oil zone varied between the fields; from normal pressure to high overpressure. It was further found that the water pressure level was fieldspecific. Normal water pressure in a few dry wells was interpreted as a probable result of leaking faults. We put forward the hypothesis that normal water pressure might be an indicator of leaking faults.