|
Gas Field Studies |
British Gas Corporation, 59 Bryanston Street, Marble Arch, London, W1A 2AZ
The Rough Gas Field was discovered in 1968. It lies in the United Kingdom Continental Shelf blocks 47/3d and 47/8b and produces from the Permian Rotliegendes sandstone in a faulted anticlinal structure. Initial reserves were 384 BCF. The field was on production until 1980 when the British Gas Corporation began developing Rough as a gas storage facility to meet peak season demand in the mid to late 1980’s. Three main facies associations are recognised from core studies of the Rotliegendes reservoir; aeolian sands, proximal fluvial sands and conglomerates, and distal sheet flood sands. The vertical arrangement of these associations within the Rotliegendes sequence define three sedimentary units which represent semi-arid alluvial fan progradation and abandonment. These units can also be recognised on electric-logs and can be correlated across the field. Reservoir porosity and permeability is largely controlled by the texture and mineralogy of the sedimentary facies, with a concomitant diagenetic influence. The geological model of facies distribution and trends in reservoir quality, together with well test data, has been used to optimise future development locations and update reservoir simulation of field behaviour in the storage mode.
