Skip to Main Content
Book Chapter

The Scott Field, Blocks 15/21a, 15/22, UK North Sea

By
Simon Guscott
Simon Guscott
Amerada Hess Limited, Scott House, Hareness Road, Aberdeen AB12 3LE, UK
Search for other works by this author on:
Ken Russell
Ken Russell
Lomond Associates, Lochwood, Johnshill, Lochwinnoch, Renfrewshire PA12 4EH, UK
Search for other works by this author on:
Andrew Thickpenny
Andrew Thickpenny
Lomond Associates, Lochwood, Johnshill, Lochwinnoch, Renfrewshire PA12 4EH, UK
Search for other works by this author on:
Robert Poddubiuk
Robert Poddubiuk
Amerada Hess Limited, 33 Grosvenor Place, London SW1 7HY, UK
Search for other works by this author on:
Published:
January 01, 2003

Abstract

The Scott Field straddles Blocks 15/21 and 15/22 on the southern flanks of the Witch Ground Graben in the Outer Moray Firth Basin, UKCS. The oil field is developed in the highly productive Upper Jurassic Humber Group sandstones of Oxfordian to Kimmeridgian age. The field was discovered in 1983, sanctioned in 1990, and produced first oil in 1993.

The field structure, effectively a large southwards tilted fault block, is compartmentalized into a series of four main pressure isolated fault blocks by mid to late Jurassic faulting. The Kimmeridge Clay Formation provides both the top seal and the source of the trapped hydrocarbons. Fluid contact, overpressure and compositional trends suggest that the trap was filled primarily from the north. Some trap-defining faults were already active during the deposition of the reservoir intervals. Well data indicate that the development of accommodation space was technically controlled during this period, with subsidence occurring more rapidly in the western areas of the field.

The Scott Field reservoir consists of two major sand packages, the Scott Sandstone Member and the Piper Sandstone Member, bounded above and below by marine flooding surfaces. The late Oxfordian Scott Sandstone Member consists of a westwards prograding marine shoreface sandstone overlain by aggradational and retrogradational back-barrier deposits. Above this, the Mid Shale is a regionally extensive flooding event separating the Scott Sandstone Member from the overlying Piper Sandstone Member. The early Kimmeridgian Piper Sandstone Member consists of stacked mass flow sandstones, overlain by a shoreface/back-barrier system. Lateral facies changes and thickness variations significantly affect reservoir distribution in both Scott and Piper intervals.

The best reservoir quality occurs within the coarsest grained, highest energy facies, particularly the shoreface and proximal washover deposits. At the crest of the field, 10400 ft TVDss, multi-Darcy permeabilities and porosities of 20% are common. However, reservoir quality declines progressively downflank due to increased quartz cementation and compaction.

The Scott Field currently produces from 23 wells supported by 20 water injectors. Current modelling is aimed at targeting bypassed oil to increase ultimate recovery. The field has presently produced 300 MMSTB of oil from forecast reserves of 440 MMSTB with an estimated ultimate recovery factor of c. 46%.

You do not currently have access to this article.

Figures & Tables

Contents

Geological Society, London, Memoirs

United Kingdom Oil and Gas Fields Commemorative Millennium Volume

J. G. Gluyas
J. G. Gluyas
Acorn Oil Gas Ltd, Staines, Middlesex, UK
Search for other works by this author on:
H. M. Hichens
H. M. Hichens
Oil and Gas Directorate, London, UK
Search for other works by this author on:
Geological Society of London
Volume
20
ISBN electronic:
9781862393950
Publication date:
January 01, 2003

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal