--> Evolution and Architecture of the Brent Delta: Principles and Pattern, by A. A. Bray, N. Butler, L. Draper, and R. N. Kimber; #90986 (1994).

Datapages, Inc.Print this page

Abstract: Evolution and Architecture of the Brent Delta: Principles and Pattern

A. A. Bray, N. Butler, L. Draper, R. N. Kimber

The Brent Province (northern North Sea, U.K. and Norwegian sectors) is widely regarded as a mature hydrocarbon province, and a total of about 1900 wells penetrate the main reservoir, the Middle Jurassic clastic wedge of the Brent Group. Modelling of thickness and facies relationships within the Brent Group has always been hampered by the lack of reliable biostratigraphic control, resulting in lithostratigraphically based correlations. This paper describes a methodology which allows parts of the succession to be tightly constrained using high resolution quantitative palynostratigraphy.

The Brent Group (Aalenian-Lower Bathonian) is generally recognized to represent the progradation of a deltaic wedge into the Viking Graben. The unit ranges from c. 300^prime-1000^prime (100-350m) thick. Three `sequences' can be recognized: (1) initial progradation of coarse inner shelf wedges from the western and eastern basin margins; (2) broadly northward progradation of inner shelf, delta front and delta plain sediments into the basin, sourced largely from the uplifted central North Sea dome. Progradation was uneven across the basin, controlled by differential subsidence within the basin. Periodic drowning of parts of the delta occurred when creation of accommodation space outpaced sediment supply; (3) a phase of middle to late Bajocian uplift, with differential erosion of underlyi g sequences, was followed by late Bajocian-Bathonian drowning. Inner shelf sediments in the North Viking Graben pass southward into contemporaneous shoreline and coastal plain sediments in the South Viking Graben.

The present study is based on detailed biostratigraphic and sedimentologic analyses of c. 140 cored successions (70,000 ft of core) which form a regional grid and a series of detailed study areas with dense well coverage.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994