Kotter and Logger oil and gas fields

The Kotter and Logger oil and gas fields are mid-size fields located in the Netherlands sector of the North Sea, about 40 km west of Den Helder and 107 km north west of Amsterdam. The Kotter and Logger oil fields produced oil from 1984/5 to 2015.

Kotter oil field
Kotter and Logger oil and gas fields is located in North Sea
Kotter and Logger oil and gas fields
Location of Kotter oil field
CountryNetherlands
RegionSouthern North Sea
Location/blockK18
Offshore/onshoreOffshore
Coordinates53°04′56″N 03°57′57″E / 53.08222°N 3.96583°E / 53.08222; 3.96583
OperatorConoco, Wintershall
OwnerConoco, Wintershall
Field history
Discovery1980 (oil), 1992 (gas)
Start of production1984
Abandonment2015
Production
Current production of oil25,000 barrels per day (~1.3×10^6 t/a)
Producing formationsCretaceous/Jurassic sandstone

The fields

edit

The Kotter oil and gas fields are located in Block K18 of the Netherlands sector of the southern North Sea.[1] The oil reservoir is a Cretaceous/Jurassic sandstone at a depth of 7,500 feet (2,300 metres) and comprises two accumulations in Vieland and Delfland sands. The gas reservoir is an Upper Rotliegendes sandstone at a depth of 4,217 to 4,337 metres, below Zechstein salt.[2][3]

The Logger oil field is in the adjacent Block L16[4] and is also a Cretaceous/Jurassic sandstone lying at a depth of 7,215 feet (2,199 metres), it has a thickness of 10 to 30 metres.[5]

The Kotter oil field was discovered by Conoco in August 1980, the Logger oil field in March 1982, and the Kotter gas field in 1992, both also discovered by Conoco.[1][3]

The properties of the reservoir/ wellhead fluids are:[1][5][2]

Wellhead fluid properties
Oil fields Kotter Gas field
Oil property Kotter Logger Gas composition and property Value
API gravity 32° 34° Methane 86.62%
Gas Oil Ratio 45 scf/bbl 48 scf/bbl Carbon dioxide 10.79%
Viscosity 4.93 cP Nitrogen 1.02%
Sulfur Low Low Hydrogen sulfide Nil
Oil in place 29 million barrels Gross calorific value 35.8 MJ/m3

Development

edit

The Kotter and Logger oil fields were developed though a number of platform installations.[1]

Offshore installations
Installation Block Configuration Water depth Function Type Legs Well slots Installed Production start Production to
Kotter Production Platform K18 Bridge linked 27 m Processing, accommodation (50 crew) Steel jacket 8 May and July 1984 September 1984 Helder A by 27.4 km 12-inch diameter pipeline
Kotter Drilling Platform K18 27 m Drilling and wellheads Steel jacket 6 24 April and June 1984 September 1984 Kotter Production
Logger Drilling Production Platform L16 Bridge linked 33 m Drilling, wellheads and production Steel jacket 4 ? July and August 1985 September 1985 Kotter Production by a 19 km 8-inch diameter pipeline
Logger Utilities Platform L16 33 m Utilities and accommodation (28 crew) Steel jacket 4 July and August 1985 September 1985

Oil from Logger was exported to Kotter. Oil from Kotter was exported to the Helder A platform and the combined flow sent to Amsterdam. Produced gas from both oil fields was flared. The K18-FB gas field adjacent to Kotter is a stranded asset with no gas transportation infrastructure and remains undeveloped.[6] The Logger installation had a water injection capability of up to 4 injection wells. Injection water was transferred from Kotter to Logger through a 19 km 6-inch pipeline.[1][7]

The Kotter production facility was originally designed for these throughputs.[1][7]

Oil production 25,000 bopd
Water production 49,000 bbl/d
Liquids production 54,000 bbl/d
Produced water 50,000 bbl/d
Water injection 60,000 bbl/d at 180 bar

The Logger installation had a production capacity of 10,000 bbl/d of oil.[1]

The K18 Golf facility aimed to produce 1.0 to 1.4 million cubic metres of gas per day.[8]

The Kotter and Logger fields were originally owned and operated by Conoco until they were taken over by Wintershall.[8] Production ceased in 2015 and the wells and installations were decommissioned and decontaminated. The platforms and jackets were removed from the field in 2019.[9]

See also

edit

References

edit
  1. ^ a b c d e f g Oilfield Publications Limited (1985). The North Sea Platform Guide. Ledbury UK: Oilfield Publications Limited. pp. 417–22, 502–5.
  2. ^ a b "Fact sheet K18-FB" (PDF). 2009. Retrieved 7 October 2021.
  3. ^ a b "K18 Oil and Gas Fields". abarrelfull. Retrieved 7 October 2021.
  4. ^ Department of Trade and Industry (1994). The Energy Report 1994. London: HMSO. pp. Map 3. ISBN 0115153802.
  5. ^ a b Goh, L. S. (1996). "The Logger oil Field (Netherlands offshore): Reservoir architecture and heterogeneity". Geology of Gas and Oil under the Netherlands. Springer. pp. 255–263. doi:10.1007/978-94-009-0121-6_21. ISBN 978-94-010-6541-2. Retrieved 7 October 2021.
  6. ^ "Fact sheet K18-FB" (PDF). www.nlog.nl. Retrieved 19 November 2021.
  7. ^ a b Quade, U. and T. Kluth. "Melting of NORM Contaminated Equipment of an Offshore Oil Platform" (PDF).
  8. ^ a b "Wintershall begins production in K18 golf field in Dutch North Sea". Offshore Energy. 2012. Retrieved 7 October 2021.
  9. ^ "Kotter Platform Lifted for Decommissioning". heavyliftnews. Retrieved 7 October 2021.