Gary J Hampson1,
Howard D. Johnson1,
Steve R. Taylor2
(1) T.H. Huxley School, Imperial College, London, United Kingdom
(2) Shell UK Exploration & Production, Aberdeen, United Kingdom
Abstract: A high-resolution tectono-stratigraphic framework for improved reservoir characterisation and near-field exploration of the Brent Group, UK North Sea
Improved reservoir characterisation in the mature Brent Province of the North Sea, aimed at maximising both in-field and near-field hydrocarbon potential, requires a clearer understanding of sub-seismic stratigraphy and facies distributions. In this context, we present a regional, high-resolution sequence stratigraphic framework for the Brent Group, UK North Sea based on sedimentological re-interpretation of 15 000 feet of core from 62 wells, combined with existing palynostratigraphy and published literature. The framework highlights the progressive structural evolution of the North Sea rift basin as a significant control on the high-resolution stratigraphy and reservoir distribution of the "Brent delta".
On a basinwide-scale, low-frequency (5-10 Ma) sequence boundaries are associated with major influxes of extrabasinal sediment, particularly from the rift basin flanks. High-frequency (0.5-1 Ma) sequences are also correlatable basinwide, but exhibit variable thickness changes across major terrace-bounding fault systems, which controlled the temporal and spatial distribution of accommodation space. Several high-frequency sequences are associated with angular truncation and/or onlap of strata, which record the growth and linkage of fault segments within the terrace-bounding fault systems. Shoreline trends are also oriented along terrace-bounding faults, implying that fault-generated topography and accommodation space variations influenced the local orientation of the depositional system(s) and their associated sandbodies. The resulting high-resolution reservoir distribution models are consistent both within, and between, established fields, which may contribute to improved ultimate recovery and identification of additional exploration potential.
AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana