Jasmine Field, North Sea, United Kingdom

The Jasmine field is situated in blocks 30/6 and 30/7a of the central North Sea. The gas and condensate field lies at a water depth of 266ft and is considered to be the UK's largest discovery since the mid-1990s.

ConocoPhillips is the operator of the field with 36.5% interest. Eni (33%) and BG Group (30.5%) are the other licensees in the project. Jasmine lies close to ConocoPhillips' producing fields, Jade and Judy.

In October 2010, the UK government approved the development of the Jasmine field. First production from the field is expected towards the end of 2012. At peak, the field is expected to produce at the rate of 88,000boepd.

Geology and reserves

The high temperature and high pressure reservoir of the field is of the Triassic age. It contains a 2,300ft deep hydrocarbon column in the Skagerrak formation. Recoverable resources present in the reservoir are estimated at 100mmboe.

Discovery

The Jasmine field was discovered in 2006 by the discovery well 30/6-6. An exploration well 30/6-06 and sidetrack well 30/6-06Z found hydrocarbon reserves in the reservoir.

Drilling

In 2007, ConocoPhillips initiated appraisal drilling at the field. Appraisal well 30/6-07 was drilled and encountered a 550ft hydrocarbon column. Tests conducted on a sidetrack well, 30/06-07Z, registered good flow rates.

An extension of the field was discovered in 2008 by the exploration well 30/6-7. The extension is located 3km north-east of the field and was drilled by the Ensco 102 drilling rig.

Two sidetrack wells, 30/6-7Y and 30/6-7X, were later drilled to establish the presence of hydrocarbons in the extension.

Field development

The field is planned to be developed in three phases. In the first phase, the West Limb and the Northern Terrace sections of the field will be developed. Drilling activities for the first phase are expected to start in the second quarter of 2011.

Installation of the Jasmine wellhead platform, the Judy riser platform and the multiphase Jasmine pipeline will be carried out in the first phase.

Jasmine wellhead platform

The Jasmine field will use the Jasmine Wellhead Platform (JWHP) for production. The platform will be supported by a four leg 5,440t jacket and nine piles. It will contain 24 slots and topsides weighing 5,500t.

The platform will be connected to the Jasmine Living Quarters through a 480t bridge, 100m in length. It will have a capacity of 300MMSCFD of gas and 90,000b/d of condensate. A test separator and flare are also part of the platform.

Judy riser platform

A new riser platform called the Judy riser platform (JRP) will be added to the production facilities at the Judy field. The JRP will be supported by a four leg 5,400t jacket with eight piles. It will contain 12 slots and topsides weighing 6,200t.

The JRP will be connected to the existing Judy platform via a 100m-long bridge, weighing 670t. It will feature primary oil and gas separation facilities, flash gas compression and product cooling facilities.

Jasmine living quarters

A 38-bed permanently manned accommodation and utility platform called Jasmine living quarters (JLQ) is part of the Jasmine field development. The JLQ will feature a four leg 3,300t jacket with four piles.

The topsides of the platform will weigh 3,100t. The platform will feature two lifeboats and a helideck.

Jasmine Pipeline

A multiphase 16in diameter production pipeline called the Jasmine pipeline will connect the JWHP and the JRP.

The total length of the pipeline will be 9km without any crossings. The pipeline will be CRA clad and be laid using the S-Lay method.

Contracts

WorleyParsons will conduct detailed engineering study for the new facilities at the Jasmine field. It was contracted in November 2010 to conduct a FEED study and provide procurement services for the JWHP, JRP, JLQ, the multiphase pipeline and other facilities. WorleyParsons earlier conducted concept and feasibility studies for the project.

ConocoPhillips contracted Subsea 7 in November 2010 for manufacturing and installing the Jasmine pipeline. Subsea 7 will also install a 9km power and communications cable between the JRP and the JLQ, along with other umbilicals and tie-ins.

AMEC was contracted for fabrication and construction of the riser platform. The company will also be responsible for the assembling and commissioning of the new Jasmine facilities.

The jackets for the JWHP and JRP will be constructed by Rossetti Marino.

In April 2010 Dragados Offshore was awarded the contract for construction of the topsides of the JWHP and JRP. Scope of work for Dragados includes engineering and construction of the jackets. Dragados will also construct the connecting bridge between the JWHP and JRP.

Italy's Saipem will be responsible for transport and installation of the platforms.