Sakhalin-I

Sakhalin-I project
Chayvo, Odoptu, Arkutun-Dagi fields
Country Russia
Region Sakhalin
Offshore/onshore offshore
Operator Exxon Neftegas Limited
Partners ExxonMobil
Sakhalin Oil & Gas Development Co. Ltd.
ONGC Videsh Ltd
Sakhalinmorneftegas-Shelf
RN-Astra
Production
Current production of oil 250,000 barrels per day (~1.2×10^7 t/a)
Estimated oil in place 2,300 million barrels (~3.1×10^8 t)
Estimated gas in place 17,100×10^9 cu ft (480×10^9 m3)

The Sakhalin-I (Russian: Сахалин-1) project, a sister project to Sakhalin-II, is a consortium for a production of oil and gas on Sakhalin Island and immediately offshore. It operates three fields in the Okhotsk Sea: Chayvo, Odoptu and Arkutun-Dagi.[1]

In 1996, the consortium completed a production-sharing agreement between the Sakhalin-I consortium, the Russian Federation and the Sakhalin government. The consortium is managed and operated by Exxon Neftegas Limited (ENL).[1]

Since 2003, when the first Sakhalin-1 well was drilled, six of the world's 10 record-setting extended reach drilling wells have been drilled at the fields of the project, using the Yastreb rig. It has set multiple industry records for depth, rate of penetration and directional drilling. On 27 August 2012, Exxon Neftegas Ltd beat its previous record by completing Z-44 Chayvo well. This ERD well reached a measured total depth of 12,376 meters (40,604 ft), making it the longest well in the world.[2]

History

Sakhalin I's fields Chayvo, Arkutun-Dagi and Odoptu were discovered by the Soviets some 20 years before the Production Sharing agreement of 1996. However these fields had never been properly assessed and a reevaluation of the commercial viability had to be carried out. To do this, factors such as the reservoir quality, producibility and well locations had to be found. 3-D seismic is the most common way to determine much of this however shallow gas reservoirs interfered with the seismic signals and blurred the images somewhat.[1]

Two campaigns of 3-D seismic was carried out along with a number of appraisal wells into the Arkutun-Dagi and Chayvo fields. The results were initially average from the appraisal wells with hydrocarbons being successfully tested, but there was a still a large amount of uncertainty involved with the project. However, in late 1998, a revaluation of the 3-D seismic data using the most advanced seismic-visualization techniques then available indicated that the hydrocarbon depth on the edge of the field could be significantly deeper than first thought. In 2000, the Chayvo 6a delineation well confirmed what was suspected, a 150 meters (490 ft) oil column. This provided the certainty that the field was commercially viable in the hostile environment with a potential to be a 1-billion-barrels (160×10^6 m3) field.[1]

In 2007, the project set a world record when extended-reach drilling (ERD) well Z-11 reached 11,282 meters (37,014 ft).[3][4] That record was broken in early 2008 with extended-reach well Z-12 reaching 11,680 meters (38,320 ft).[4] Both extended-reach wells are in the Chayvo field and reach over 11 kilometers (6.8 mi).[4] As of early 2008, the Chayvo field contains 17 of the world's 30 longest extended-reach-drilling wells.[4] However, in May 2008, both world records of ERD well were surpassed by the GSF Rig 127 operated by Transocean, which drilled the ERD well BD-04A in the Al Shaheen oil field in Qatar. This ERD well was drilled to a record measured depth of 12,289 meters (40,318 ft) including a record horizontal reach of 10,902 meters (35,768 ft) in 36 days.[5]

On 28 January 2011, Exxon Neftegas Ltd., operator of the Sakhalin-1 project, drilled the then world's longest extended-reach well. It has surpassed both the Al Shaheen well and the previous decades-long leader Kola Superdeep Borehole as the world's longest borehole. The Odoptu OP-11 Well reached a measured total depth of 12,345 meters (40,502 ft) and a horizontal displacement of 11,475 meters (37,648 ft). Exxon Neftegas completed the well in 60 days.[6]

On 27 August 2012, Exxon Neftegas Ltd beat its own record by completing Z-44 Chayvo well. This ERD well reached a measured total depth of 12,376 meters (40,604 ft).[2]

Development

The three fields will be developed in this order: Chayvo, Odoptu and Arkutun-Dagi. The total project is estimated to cost US$10–12 billion, making it the largest direct investment in Russia from foreign sources. It is also estimated that nearly 13,000 jobs will be created either directly or indirectly. Approximately $2.8 billion has already been spent, which helped lower unemployment and improved the tax base of the regional government. The fields are projected to yield 2.3 billion barrels (370×10^6 m3) of oil and 17.1 trillion cubic feet (480×10^9 m3) of natural gas.[1]

In 2007, the consortium reached its production goal of 250,000 barrels per day (40,000 m3/d) of oil.[7] In addition, natural gas production for the peak winter season in 2007 was 140 million cubic feet per day (4.0×10^6 m3/d).[7]

The first rig is in place for Sakhalin-I, Yastreb, is the most powerful land rig in the world. Parker Drilling Company is the operator of the 52 meters (171 ft) high rig. Although the rig is land based it will drill more than 20 extended-reach wells 10 kilometers (6.2 mi) horizontally out into the Sea of Okhotsk, and 2,600 meters (8,500 ft) in depth. This land-based offshore drilling arrangement is needed because the Sea of Okhotsk is frozen about four months out of the year. The rig is designed to be resistant to the earthquakes that frequent the area, and operate in the −40 °C (−40 °F) temperatures that can occur in the winter.[1]

As part of the project, Russia is in the process of building a 220-kilometre (140 mi) pipeline across the Tatar Strait from Sakhalin Island to De-Kastri oil terminal on the Russian mainland. From De-Kastri it will be loaded onto tankers for transport to East Asian markets.[1]

Consortium

The consortium consist of:

Both Russian entities are Rosneft affiliates.[8]

The fields are operated by Exxon Neftegas Limited.

Environmental concerns

Scientists and environmental groups voice concern that Sakhalin-I threatens the critically endangered western gray whale population. Approximately 130 western gray whales remain, of which only 30-35 are reproductive females. These whales only feed during the summer and autumn, in feeding grounds which happen to lie adjacent to Sakhalin-I project onshore and offshore facilities and associated activities along the northeast coast of Sakhalin Island.[9]

Since 2006, the International Union for the Conservation of Nature (IUCN) has convened the Western Gray Whale Advisory Panel (WGWAP), consisting of marine scientists who provide expert analysis and advice concerning impacts on the endangered western gray whale population from oil and gas projects in the area, including Sakhalin-I.[10] In February 2009, the WGWAP reported that the number of western gray whales observed in the near-shore (primary) feeding area had significantly declined in the summer of 2008, which coincides with industrial activities conducted by ENL (and other companies) in the area. The WGWAP suggested a moratorium on all industrial activities in the area until their effects had been studied or plans made to mitigate any negative effects of industrial activity had been implemented.[11] Cooperation of Sakhalin Energy-ENL with the scientific panel investigating gray whales was hampered by confidentiality agreements and by ENL's lack of motivation to cooperate with the process.[12] In April 2009, the WGWAP reiterated its call for a moratorium, leading Sakhalin-I project sponsor, Sakhalin Energy, to suspend its planned 2009 seismic testing.[13][14] which was welcomed by the WWF and other environmental groups, however other petroleum companies including BP, Exxon and Rosneft were still due to carry out seismic tests in that year.[15]

See also

References

  1. 1 2 3 4 5 6 7 "Sakhalin-1: A New Frontier" - PennWell Custom Publishing (c/o of ExxonMobil)
  2. 1 2 Sakhalin-1 Project Breaks Own Record for Drilling World`s Longest Extended-Reach Well
  3. ↑ "ExxonMobil Announces Drilling of World-Record Well". ExxonMobil. Business Wire. 24 April 2007.
  4. 1 2 3 4 Watkins, Eric. - "ExxonMobil drills record extended-reach well at Sakhalin-1" - Oil & Gas Journal - (c/o mapsearch.com) - 11 February 2008
  5. ↑ Transocean Ltd. Press Release (2008). "Transocean GSF Rig 127 Drills Deepest Extended-Reach Well", Accessed 2009-10-21
  6. ↑ Sakhalin-1 Project Drills World's Longest Extended-Reach Well
  7. 1 2 "Sakhalin-1 Project Production Goal Achieved". ExxonMobil. Business Wire. 14 February 2007.
  8. ↑ Project Information Overview - Sakhalin-1 Project Website
  9. ↑ "IUCN - Initiative Background". International Union for Conservation of Nature.
  10. ↑ http://www.iucn.org/wgwap/about_the_initiative/history_of_engagement/ Archived August 4, 2009, at the Wayback Machine.
  11. ↑ "17 Update on Proposed Activity on the Sakhalin Shelf". Report of the Western Gray Whale Advisory Panel at its Fifth Meeting (PDF). International Union for Conservation of Nature. December 2008. pp. 31–33. Retrieved 2011-02-01.
  12. ↑ "18 Explicit Discussion of WGWAP modus operandi, Potential Revision of ToR, Structure and Schedule of Panel Meetings". Report of the Western Gray Whale Advisory Panel at its Fifth Meeting (PDF). International Union for Conservation of Nature. December 2008. pp. 33–36. Retrieved 2011-02-01.
  13. ↑ "Western Gray Whales Get a Break From Noisy Oil Development". ens-newswire. 24 April 2009.
  14. ↑ "IUCN welcomes reprieve for whales". International Union for Conservation of Nature. 28 April 2009.
  15. ↑ "Gray whales granted rare reprieve". BBC News. 2009-04-24. Retrieved 2010-05-23.

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