The Norwegian Barents Sea: Experience On Drilling Of The First Exploration Well On The Fedynskiy High

Abstract

Summary Drilling through carbonates and open karsts is very challenging due to potential severe mud losses and hole instability. In case hydrogen sulphide is present in high concentrations in these geological conditions, this could lead to hazards that are difficult to cope with. The objective is to reveal innovative drilling experience of the first ever exploration well on the Fedynskiy High in the Norwegian Barents Sea, on the borderline of Norway in the Barents Sea. Various methods of drilling and coring in karstified carbonate formations with presence of sour gas in high concentrations have been explored. During planning, it was demonstrated that modern modelling techniques allow comprehensive analysis of H2S formation process in the reservoir fluid in the Norwegian Barents Sea, especially if both chemical and regional factors are taken into account. This is the first frontier exploration well drilled from a mobile unit on the NCS remotely with risks associated with karst and H2S. New approaches have been developed to deliver the well in a safe and efficient manner. Much effort has been used on modeling and regional studies. Experience uncovers new cost-efficient and safe solutions that can be considered in other regions worldwide with similar overall risk picture.