The Balmoral Field, Block 16/21, UK North Sea

1991 ◽  
Vol 14 (1) ◽  
pp. 237-244 ◽  
Author(s):  
P. C. Tonkin ◽  
A. R. Fraser
Keyword(s):  
North Sea ◽  
Reservoir Pressure ◽  
Production Facility ◽  
Lower Section ◽  
Submarine Fan ◽  
The North ◽  
Recoverable Reserves ◽  
The North Sea ◽  
Structural High ◽  
Northeast Coast

AbstractThe Balmoral oilfield operated by Sun Oil Britain Ltd, lies within UK blocks 16/21 b and 16/21c, 140 miles off the northeast coast of Scotland. The field was discovered by the drilling of well 16/21-1 in 1975. Andrew Formation sandstones of Late Palaeocene age form the reservoir, which is sealed by Lista Formation claystones. The sandstones are of submarine fan origin sourced from the north and west of the area. The trap is structural, formed by the differential compaction of Tertiary sediments over a Palaeozoic structural high.The upper section of the reservoir consists of two units of consolidated sandstone (units U and M) of channel-fill origin separated by a channel abandonment claystone (unit SI). Porosities for these sandstone units range from 17-28% and permeabilities are up to 3300 md. The lower section of the reservoir consists of friable sandstones (Unit F), characterized by grain-coating clays which have prevented consolidation. This unit is mainly of submarine fan lobe origin. Porosities range from 20-28% and permeabilities are up to 700 md.Balmoral came on stream in November 1986. Recoverable reserves are estimated to be 68 MMBBL of undersaturated 39.9° API oil, and annual production remains at the 35 000 BOPD plateau rate.The oil is produced from 12 wells with reservoir pressure maintained by the injection of water through a further six wells. These are all tied into a floating production vessel (FPV), the first such purpose-built production facility to be used in the North Sea. Production in Balmoral is expected to continue until the year 2001.

The Ivanhoe and Rob Roy Fields, Blocks 15/21a-b, UK North Sea

1991 ◽  
Vol 14 (1) ◽  
pp. 331-338 ◽  
Author(s):  
R. H. Parker
Keyword(s):  
North Sea ◽  
Upper Jurassic ◽  
Rock Properties ◽  
Production Facility ◽  
Injection Wells ◽  
Recoverable Reserves ◽  
Fault Block ◽  
Moray Firth ◽  
Sandstone Formation ◽  
Northeast Coast

AbstractThe Ivanhoe and Rob Roy Fields are located in the Outer Moray Firth Basin, seventy nautical miles off the northeast coast of Scotland. The Ivanhoe Field was discovered in 1975, and the Rob Roy Field in 1984. The reserves in both fields occur in tilted fault block traps of Upper Jurassic, Piper Sandstone Formation. Estimated total recoverable reserves amount to 100 MMBBL and 62 BCF. The fields are separated by a water corridor approximately 1 km wide. Both fields contain two reservoir sandstone units, an upper and lower, locally termed the Supra Piper Sandstone and Main Piper Sandstone respectively. The reservoirs in both fields exhibit excellent rock' properties with porosities up to 28% and permeabilities of several Darcies.Each field is developed via a subsea manifold surrounded by a cluster of production and injection wells, of which two were pre-drilled on Ivanhoe and six pre-drilled on Rob Roy. This allowed rapid achievement of the 60 000 BOPD plateau oil production rate soon after commissioning of facilities in July 1989. The two subsea manifolds are tied into a single subsea production manifold which connects with a Floating Production Facility. Crude oil is exported to the Claymore A Platform and gas to the Tartan A Platform.

The Flora Field, Blocks 31/26a, 31/26c, UK North Sea

2003 ◽  
Vol 20 (1) ◽  
pp. 549-555 ◽  
Author(s):  
R. D. Hayward ◽  
C. A. L. Martin ◽  
D. Harrison ◽  
G. Van Dort ◽  
S. Guthrie ◽  
...  
Keyword(s):  
North Sea ◽  
Upper Jurassic ◽  
Water Contact ◽  
Upper Carboniferous ◽  
The North ◽  
Recoverable Reserves ◽  
The North Sea ◽  
Oil Water ◽  
The Uk ◽  
Clay Formation

AbstractThe Flora Field straddles Blocks 31/26a and 31/26c of the UK sector of the North Sea on the southern margin of the Central Graben. The field is located on the Grensen Nose, a long-lived structural high, and was discovered by the Amerada Hess operated well 31/26a-12 in mid-1997.The Flora Field accumulation is reservoired within the Flora Sandstone, an Upper Carboniferous fluvial deposit, and a thin Upper Jurassic veneer, trapped within a tilted fault block. Oil is sourced principally from the Kimmeridge Clay Formation of the Central Graben and is sealed by overlying Lower Cretaceous marls and Upper Cretaceous Chalk Group.Reservoir quality is generally good with average net/gross of 85% and porosity of 21%, although permeability (Kh) exhibits a great deal of heterogeneity with a range of 0.1 to <10000mD (average 300 mD). The reservoir suffers both sub-horizontal (floodplain shales) and vertical (faults) compartmentalization, as well as fracturing and a tar mat at the oil-water contact modifying flow and sweep of the reservoir. Expected recoverable reserves currently stand at 13 MMBBL

The Magnus Field, Block 211/7a, 12a, UK North Sea

1991 ◽  
Vol 14 (1) ◽  
pp. 153-157 ◽  
Author(s):  
M. Shepherd
Keyword(s):  
North Sea ◽  
Upper Jurassic ◽  
Hydrocarbon Source Rock ◽  
Submarine Fan ◽  
Oil Accumulation ◽  
The North ◽  
Fault Block ◽  
The North Sea ◽  
The Uk ◽  
Clay Formation

abstractMagnus is the most northerly producing field in the UK sector of the North Sea. The oil accumulation occurs within sandstones of an Upper Jurassic submarine fan sequence. The combination trap style consists of reservoir truncation by unconformity at the crest of the easterly dipping fault block structure and a stratigraphic pinchout element at the northern and southern limits of the sand rich fan. The reservoir is enveloped by the likely hydrocarbon source rock, the organic rich mudstones of the Kimmeridge Clay Formation.

The Gryphon, Maclure, Tullich and Ballindalloch fields, Blocks 9/18b, 9/18c, 9/19a, 9/23d and 9/24e, UK North Sea

2020 ◽  
Vol 52 (1) ◽  
pp. 837-849 ◽  
Author(s):  
F. Pelletier ◽  
C. Gunn
Keyword(s):  
North Sea ◽  
Seismic Data ◽  
Oil Production ◽  
Production Data ◽  
Final Phase ◽  
Submarine Fan ◽  
Initial Development ◽  
The North ◽  
Early Tertiary ◽  
The North Sea

AbstractThe Gryphon Field was discovered in 1987 in Quadrant 9 in the Beryl Embayment. Oil was encountered in a thick Balder Formation sandstone, and the reservoir was interpreted as lobes of a submarine fan system, such as many of the prolific early Tertiary fields in the North Sea. After an extensive appraisal phase, oil production started in 1993 through the Gryphon floating production, storage and offloading vessel.After a successful initial development phase, the integration of production data, improved and regularly acquired seismic data, and a better geological understanding resulted in the identification of sandstone intrusions. These have since been interpreted to form a volumetrically significant part of the Gryphon reservoir. The drilling of further infill wells, and the development of satellite fields Maclure, Tullich and the future Ballindalloch, ensued from this change to the geological model. To date, the Gryphon, Maclure and Tullich fields have produced more than 200 MMbbl of oil compared to an initial reserve estimate of 151 MMbbl.Although the current and mid-term focus remains on maximizing oil production, the final phase of the wider Gryphon area fields’ development should see the production of the regional gas cap.

The Maria Field, Block 16/29a, UK North Sea

2020 ◽  
Vol 52 (1) ◽  
pp. 875-885 ◽  
Author(s):  
I. N. Stephens ◽  
S. Small ◽  
P. H. Wood
Keyword(s):  
North Sea ◽  
Upper Jurassic ◽  
Reservoir Properties ◽  
The North ◽  
Recoverable Reserves ◽  
Fault Block ◽  
Production Wells ◽  
The North Sea ◽  
The Uk ◽  
Clay Formation

AbstractThe Maria oilfield is located on a fault-bounded terrace in Block 16/29a of the UK sector of the North Sea, at the intersection of the South Viking Graben and the eastern Witch Ground Graben. The field was discovered in December 1993 by the 16/29a-11Y well and was confirmed by two further appraisal wells. The reservoir consists of shoreface sandstones of the Jurassic Fulmar Formation. The Jurassic sandstones, ranging from 100 to 180 ft in thickness, have variable reservoir properties, with porosities ranging from 10 to 18% and permeabilities from 1 to 300 mD. Hydrocarbons are trapped in a truncated rotated fault block, striking NW–SE. The reservoir sequence is sealed by Kimmeridge Clay Formation and Heather Formation claystones. Geochemical analysis suggests that Middle Jurassic Pentland Formation and Upper Jurassic Kimmeridge Clay Formation mudstones have been the source of the Maria hydrocarbons. Estimated recoverable reserves are 10.6 MMbbl and 67 bcf (21.8 MMboe). Two further production wells were drilled in 2018 to access unexploited areas.

The North Brae and Beinn Fields, Block 16/7a, UK North Sea

2003 ◽  
Vol 20 (1) ◽  
pp. 199-209 ◽  
Author(s):  
J. A. Brehm
Keyword(s):  
North Sea ◽  
Normal Faulting ◽  
The South ◽  
Submarine Fan ◽  
The North ◽  
Structural Inversion ◽  
The North Sea ◽  
The Uk ◽  
Oil Company ◽  
Gas Recycling

AbstractNorth Brae is located in Block 16/07a, and was discovered in 1975 by Pan Ocean Oil Company. The field was purchased by Marathon Oil Company in 1976 and was delineated in the early 1980s. Production by gas recycling was commenced in 1988. Liquid reserves are estimated at 207 MMBBLs with recoverable dry gas of 800 BCF.The North Brae Field is one of three gas/condensate fields in the Brae fields area of the South Viking Graben in the UK Sector of the North Sea. The reservoir is part of a large turbidite and debris flow, submarine fan system that also encompasses the East Brae and Kingfisher fields to the northeast of North Brae. North Brae is located at the proximal end of this fan system, and channelized massive conglomerates and sandstones characterize its reservoirs. The stratigraphy of the fan system was influenced by highly variable changes in relative sea level that controlled sediment input. Structural activity was also important, such as syn-sedimentary normal faulting related to the subsidence of the South Viking Graben, and structural inversion, in a series of regional compressive episodes commencing in the Late Jurassic and Early Cretaceous.

The Clyde Field, Block 30/17b, UK North Sea

1991 ◽  
Vol 14 (1) ◽  
pp. 279-285
Author(s):  
D. A. Stevens ◽  
R. J. Wallis
Keyword(s):  
Production Rate ◽  
North Sea ◽  
Late Jurassic ◽  
Water Injection ◽  
Reservoir Quality ◽  
Reservoir Pressure ◽  
Shallow Marine ◽  
The North ◽  
Fault Block ◽  
The North Sea

AbstractThe Clyde Field, which was discovered in 1978, is located on the SW edge of the North Sea Central Graben. The reservoir is developed with Late Jurassic shallow marine sands of the Fulmar Sand Formation. An estimated 408 MMBBL of oil is present (Annex B), of which 154 MMBBL is considered recoverable.The structure of the Clyde Field takes the form of a rotated Jurassic fault block, truncated at its crest by a major unconformity. Oil is retained within a combination trap, sourced from Late Jurassic Kimmeridge Clay thermally matured in the highly productive basinal lows, adjacent to the field.Reservoir sand quality is highly variable, ranging from excellent with permeabilities in excess of Id, to poor with permeabilities of less than 1 md. The principal control on reservoir quality appears to be original depositional texture, although strong diagenetic effects are also present.Production is from a single, centrally located, platform provided with thirty slots. Aquifer support is insufficient to maintain reservoir pressure at the current plateau production rate of 50 000 BOPD and so a programme of water injection has been implemented.

Sign in / Sign up

Export Citation Format

Share Document