The Galata Project, situated about 20km from the eastern port of Varna, is being developed by Melrose Resources. The Galata gas field is 23km offshore Bulgaria in the Black Sea.
The field lies at a water depth of 35m and has gross proved and recoverable reserves of 49 billion cubic feet (bcf), and proved and probable reserves of 81bcf.
Melrose Resources controls a 100% interest in the project field through its subsidiary Petreco.
The development of the Galata field, a 100% interest in the exploration permit for the remainder of block-III and block Kaliakra offshore Bulgaria are the activities involved in the Galata Field project.
The Galata gas field is now being converted into a gas storage facility, further developing Bulgaria as a key gas transit country. As per the plan, the field was shut down in January 2009. About 8.5bcf of gas reserves were left at the field.
Melrose had talks with the new Bulgarian Government to get approval to complete the Karvarna field development as a subsea tie back and for the gas injection at the Galata gas storage project.
The company also plans to speed up the activities related to completing the agreements required for the commencement of the Galata gas storage project.
Karvarna and Kaliakra are two other fields being developed within the Galata project. First gas production from the two fields began in November 2010 after receiving government approvals in November 2009.
Gas storage facility
A memorandum of understanding was signed between Melrose and the state-owned gas utility Bulgargaz at the end of 2007. As per the agreement, the company and Bulgargaz conducted an assessment of the feasibility of converting the gas field into a storage facility.
The project was found feasible and further plan was drawn for three phase conversion of the field. A capital expenditure of $90m was fixed for developing the storage facility with a capacity of 1.8 billion cubic metres (bcm).
The first phase of development of the gas storage facility started in 2009 and involved field compression. The second and third phases will involve tying-back Galata second well and installation of metering facilities respectively.
The first phase required an investment of $30m. Phase I will provide storage capacity of 0.7bcm. Phases II and III with an investment of $30m each will raise the capacity to 1.2bcm and 1.7bcm, respectively.
Galata field development
The field was discovered by Texaco in June 1993. A 3D survey at the field was done in 1995 and an appraisal of Galata-2 was completed by Texaco in 1996. The field was not developed by Texaco due to its relatively smaller size.
Melrose acquired the Galata gas field in January 1999. The company won complete ownership of Galata Production Concession and the two exploration blocks, including 91-III and Kaliakra 99 in 2001.
A sales contract to supply at least 14bcf of gas for the first two years of production was signed with Bulgargaz in November 2001.
In January 2004 the production wells GP No 1 and GP No 2 on the Galata Gas field development were drilled and completed. The drilling result of GP No 2 well has outlined an extension to the gas reservoir in the northern fault block of the field.
On completion of the production well drilling, the reserves were estimated to be 80-90bcf. The production began in 2004.
Platform installation, jacket positioning on the seabed and piling started in October 2003. The offshore platform and other onshore facilities at the field were completed in April 2004.
The company reported 7.4Bcf of gas from the Galata field in 2008. Daily deliveries averaged 20.2mcf (million cubic feet) of gas.
The peak production of 51mscf per day occurred at the field in 2005. The field has met the gas requirement of around 8% of Bulgaria in 2008.
Drilling and exploration
Melrose is also focusing on other exploration prospects located on the Galata block. The Kavarna and Kaliakra discoveries were made using subsea wells tied back to the project platform with export through existing offshore pipelines and onshore processing plants.
The existing pipeline was laid by GMC in 2004. Production from the two discoveries will replace production volumes from Galata by 2011.
The company aims to drill an appraisal well on the Kaliakra discovery, which has gas reserves of about 47bcf.
Melrose announced successful exploration of the well in October 2008. It was drilled to a total depth of 2,899ft, where the Palaeocene reservoir was hit.
The drilling was done with the Prometeu jack-up rig, which can work at water depths of 300ft and drill to a depth of 19,800ft.
The drilling of the Kaliakra No 2 well was completed in August 2009, 1.8km west of the Kaliakra No 1 well, which was drilled earlier.
The Kaliakra No 2 well permeated the top of a Paleocene reservoir at a depth of 2,679ft and found 67ft of net gas pay, thicker than the 31ft encountered in Kaliakra No 1.
Results from the Kaliakra field indicated 57bcf of reserves.