Development Of The Beryl A Field

Abstract Development drilling from the Beryl 'A' Platform has been in progress for over two years. A total of twelve wells nave been completed with two more nearing completion. Drilling has been concentrated on delineating the Upper Beryl Reservoir, which represents the main producing horizon. Gas injection was started in November 1977. To date, injection performance of the Upper Beryl has been encouraging and producing performance indicates a favourable gravity segregation producing mechanism is operative. INTRODUCTION The Beryl Field is located in Block 9/l3a, 95 miles southeast of the Shetland Islands, in U.K. waters. Figure 1 shows location of the Beryl Field relative to other North Sea Fields. Mobil North Sea Ltd. is operator for the Block 9/13a group, which includes Amerada Hess, North Sea Inc., Gas Council (Exploration) Ltd. and British National Oil Corporation. The Beryl Field discovery well, 9/13-1 (551) was tested from a Jurassic sand at 10,000 feet in September, 1972. Well 9/13-2 was drilled in 1973 and tested a Triassic sand. Figure 2 shows the location of these two wells. Economic analyses, based on seismic mapping and the first two wells, indicated the field was commercial and a concrete gravity base ('Condeep') platform was ordered in July, 1973. Two platform positioning wells, 9/13-5 and 9/l3-6A, were drilled prior to platform tow-out. BERYL 'A' PLATFORM Beryl 'A' platform was towed-out and set in 390 feet of water in. July, 1975, less than 24 months from contract award. In September, 1975, an articulated loading column was set about one mile from the platform and tied into the 900,000 barrels of storage in the platform base by a 32 inch pipeline. Original design concept for the Platform was to provide a capability for extra producing facilities to serve as a central processing, storage and loading point for other expected discoveries in Block 9/13. Current oil and gas handling capacity is 300,000 BOPD and 150 MMCFD respectively. Gas handling capacity can be expanded up to 300 MMCFD by adding additional gas compressors. Pertinent data on the Beryl 'A' platform has been published.(1) DEVELOPMENT DRILLING Development drilling from the platform was initiated with one rig in February, 1976 and with the second rig in April, 1976. First production on the platform was in June, 1976, about 44 months from field discovery date. As of June 1978, twelve platform wells have been drilled and completed with two other wells drilling in the Jurassic. In addition, discovery well 9/13-1 was completed as a subsea producer and tied back to the platform in July 1976. There are 40 well conductor slots on the Beryl 'A' platform. An estimated area of about 5500 acres will be developed by wells directionally drilled from the platform. This is based on the estimated productive area within an assumed 11000 foot drilling radius around the platform, shown as the Beryl 'A' Area on Figure 2.