The Norne Field - Exploration History & Reservoir Development Strategy
Authors: Gjerstad Helge M. , Steffensen lvar , Skagen Jan I. 
Published: October 2008

The Norne Field was discovered in December 1991, after 8 years of discouraging exploration activity in the Nordland /&I1 areas offshore Mid-Norway. A final well was drilled as alternative to the scheduled relinquishment, - and a major oil field was found. 3D-seismic has been acquired, one appraisal well drilled to confirm reserves and one exploration well has proven minor reserves in a north-eastern extension of the field. The reservoir comprises sandstones of Middle and Late Jurassic age of excellent quality. Recoverable oil is 72 million Sm3 (453 million barrels). The field will be produced by pressure maintenance, with injection of water and produced gas. AN wells, 7 producers, 5 water injectors and 2 gas injectors, will be horizontal in the reservoir sections. 6 pre-drilled wells are sufficient to obtain plateau oil production rate from production start-up based on an average maximum well production rate in excess of 6000 Sm3/d. Plateau production is expected to maintain for about 3-4 years. Reservoir simulation models will be an important tool for understanding the reservoir dynamics and for continuous optimization of the development plan. Information from the development wells will be incorporated in the simulation model on regular basis for history matching and further predictions. With production start-up within 1 July 1997, a significant reduction in time from discovery until production is achieved.

INTRODUCTION

The Norne Field is located in blocks 6608110 and 650811 in the Nordland II area on the Norwegian continental shelf. The distance to shore is about 200 km (124 miles) and 85 km (53 miles) to the Heidrun Field in the southwest (Fig. 1 and 2). The water depth in the area is 370- 390 meter. Nome was discovered in December 1991, and appraised to the north by a second well during the winter of 1993. Based on the results from these two wells, a development project was established with the objective to investigate the economical potential and to prepare a Plan for Development and Operations (PDO).

EXPLORATION HISTORY

The first well in the Nordland I&II areas was drilled by Statoil in 1983, on a rotated fault block of Jurassic age. It was proven dry. This drilling was followed by another 5 wells on the Trøndelag Platform in the Nordland I area, - all dry wells (Fig. 2). After the discouraging result on the Platform, the oil companies once again moved their interest to the west, where such promising discoveries as the Heidrun Field had been done further south in 1985. The 10B concession round in 1986 focused on the Denna Terrace and the Nordland Ridge north of the Heidrun Field. Drilling of five wells in the period 1987 to 1989 on the Nordland Ridge on Cretaceous and Jurassic play models on the Dørnna Terrace did not increase the optimism for the area. The Production License 128 (PL 128) was awarded in February 1986 and comprises blocks 660811 0 and 660811 1. The first two wells in the Norne license were both negative. The work commitment within the license was fulfilled by the end of 1989 and the licensees were ready for a 100% relinquishment of the area.