Sequence Stratigraphic-Structural Analysis of the East Midlands Carboniferous Oil Field, UK: Implications for Fluvial Reservoir Models
John F. Aitken and David G. Quirk
The integration of seismic, well log and core data from the Scampton Nort and Welton oil fields, Lincolnshire, UK, has enabled the development of a sequenc stratigraphic-structural model for late Namurian and early Westphalian fluvial reservoirs. The tectonic and sequence stratigraphic setting is remarkably similar to that in the Southern North Sea which extends more than 250 km to the east. Close onshore well spacing, supplemented with coal exploration borehole data, provides a excellent analogue for new Carboniferous Southern North Sea developments an prospects.
The reservoirs comprise medium-grained, low sinuosity fluvial aggradational packages within a coal-bearing, fluvio-deltaic depositional environment. Althoug major active faults occur within the Namurian, tectonic activity had ceased by the start of the Westphalian which has a tramline-like appearance on seismic.
The reservoirs are poorly interconnected as a consequence of small-scal faults and extensive shale baffles, which have resulted in considerable production problems, accentuated by an initial poor reservoir correlation. Palynology has proven to be highly imprecise, consequently, the use of seismic picks as chronostratigraphic markers combined with the coal stratigraphy from British Coal boreholes and the application of sequence stratigraphic concepts has enabled a more precise reservoir correlation to be made.
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California