Yuri Korchagin Field, Caspian Sea, Russia

The Yuri Korchagin field is located in the Russian waters of the North Caspian Sea at a sea depth of 11-13m. It is located 180km from the city of Astrakhan and 240km from Makhachkala.

The field was discovered by Lukoil in 2000 and is owned by its subsidiary Lukoil Nizhnevolzhskneft. Its first oil was extracted on 28 April 2010. The proved, probable and possible hydrocarbon reserves in the Yuri Korchagin field are estimated to be 570 million barrels of oil equivalent.

Lukoil expects to extract 2.5 million tonnes of oil and one billion cubic metres of gas per year. In 2010, the output is expected to be 343,000t of oil.

Lukoil spent R34.4bn ($1.12bn) on the field development between 2004 and 2009. The field was named after the former secretary of the company's board of directors.

In October 2010, first oil from the field was loaded on to the Caspian Stream tanker.

Yuri Korchagin wells

"The Yuri Korchagin field was named after the former secretary of the company's board of directors."

The Yuri Korchagin field will have 30 wells, comprising 26 production wells, one gas-injection well and three water-injection wells. Two wells were drilled at the time of the field's commissioning in April 2010. The first one is an oil production well and the second was drilled to extract gas to supply power to the facility.

A third well, for water injection, was drilled during the second quarter of 2010.

In a unique engineering procedure, the wells have been drilled horizontally for a length of about 5km.

The radial placement of the wells enables in their simultaneous drilling. The drilling process is monitored through a satellite channel from onshore.

The drilling work was contracted to Moscow-based drilling company BKE Shelf.

Offshore platform

A fixed offshore ice-resistant platform (LSP-1) is the main production facility at the Yuri Korchagin field. It drills, collects and transports hydrocarbons from the field.

The LSP-1 is 95.5m long, 72.2m wide, weighs 25,655t and is 86.6m above sea level. The platform was built at the Astrakhansky Korabel plant. It was towed to the field from Astrakhan in July 2009 and was assembled during the third quarter of that year.

The platform houses a 560t drilling complex and two cranes. It can drill wells up to a depth of 7,400m and the two cranes have a load capacity of 70t. J Ray McDermott was responsible for installation of the platform. Stroytransgaz was responsible for the construction of the technological complex of the platform.

"Lukoil will extract 2.5 million tonnes of oil and one billion cubic metres of gas per year."

An additional platform, named LSP-2, provides accommodation to the field's personnel. The platform is 41.5m long, 40.2m wide, weighs 1,340t and is 38m above sea level. The platform was constructed at Lukoil-Kaliningradmorneft's hardware factory. Equipment was assembled at the Astrakhan Shipyard.

LSP-2 was towed to the field and the topside assembled in May 2009. The topside includes living quarters for 105 personnel, a medical facility, store rooms, ship repair and service facilities, a helideck and rescue equipment. The platform can self-sustain for 15 days.

LSP-1 and LSP-2 are connected by a 74.2m-long bridge. The bridge was assembled in August 2009, marking the completion of work on the offshore facility.

Lukoil claims that the results of the satellite monitoring of the North Caspian Sea showed that there have been no oil spills during the assembling of the platform. The satellite monitoring is carried out by the Research and Development Center ScanX to trace pollution in the Caspian waters.

Phase II of the field development includes the installation of a conductor-platform. A 9km-long pipeline will transfer produced oil from the new platform to the LSP-1. Produced gas from the LSP-1 will be transferred to the new platform.

Floating storage unit

"The LSP-1 is 95.5m long, 72.2m wide and weighs 25,655t."

The storage unit lies 58km away from the production platform, outside the ice zone of the Caspian Sea. It is connected to the IRP-1 via a subsea pipeline. The unit has deadweight of 28,000t and was built in Baku.

The floating storage unit is moored to a single-buoy mooring (SBM). The SBM is assembled at a sea depth of 20.5m and rises to 27.2m above sea level.

The 1,725t SBM is fixed to the sea bed with five piles of 2,130mm diameter each.

The SBM-floating storage unit is connected to the offshore platform via a 58km-long pipeline, which has a diameter of 300mm and a wall thickness of 16mm.

Hydrocarbons from the storage unit are transported to refineries in shuttle tankers that weigh 6,000 to 12,000t.