The Zawtika project is located in the Gulf of Martaban, offshore Myanmar. Credit: Sembcorp Marine.
The project includes the development of three fields, namely Zawtika, Kakonna and Gawthaka in Blocks M9 and M11. Credit: mohd nasrullah ahmad/
Phase 1D of the Zawtika project is currently ongoing. Credit: aor/

The Zawtika project includes the development of the Zawtika, Kakonna and Gawthaka fields, located in blocks M9 and M11 of the Gulf of Martaban, offshore Myanmar.

The Petroleum Authority of Thailand Exploration and Production International (PTTEP International) is the operator of the project and owns an 80% interest, with Myanma Oil and Gas Enterprise (MOGE) holding the remaining 20%.

The $2bn project initially started delivering natural gas for domestic purposes in Myanmar in March 2014 at a rate of 60 million standard cubic feet per day (MMscf/d). In August 2014, it began exporting natural gas to Thailand at a rate of 240MMscf/d.

The project is currently in the final Phase 1D, which is expected to be commissioned in 2025. The production capacity of the project will be 400MMscf/d.

Myanmar is estimated to contain 3.2 billion barrels of oil and 18 trillion cubic feet (tcf) of natural gas reserves. Almost a quarter of this production is sent to Thailand. Output from the Zawtika field is also being sent to Thailand, increasing its imports to between 1.2 and 1.3 billion cubic feet each day.

Discovery and geology of Myanmar’s fields

The Zawtika project covers an area of 11,746km².

All three fields of the project were discovered in 2007. Zawtika was discovered by the Zawtika-1 well in 2007. It hit seven significant gas reservoirs and accumulations.

Gawthaka was discovered by the Gawthaka-1 well, which was drilled to a depth of 3,380m and flowed at the rate of 9.4MMscf/d.

The drilling of the Kakonna-1 well led to the discovery of the Kakonna field. The well indicated a link between the northern and southern parts of Block M9. It flowed at the rate of around 21.2MMscf/d and 8.6MMscf/d during two tests.

The Zawtika project fields are biogenic gas formations consisting of reservoirs of Miocene-Pliocene Delta Front sandstones, located at a depth of 750m to 1,580m, and shallower reservoirs in the Pleistocene strata at depths of 500m.

The project is estimated to contain around two trillion cubic feet (tcf) of gas.

Drilling and appraisal of the Burmese gas fields

PTTEP drilled seven exploration wells in Block M9 in 2007 after the discovery of the Zawtika field: Gawthaka-1, Kakonna-1, Zawtika-1, Zawtika-2, Zawtika-3, Zawtika-4 and Zawtika-5.

The Zawtika-2 well, located in the southern part of Block M9, was drilled to a depth of 3,500m. It encountered significant quantities of natural gas in six zones and flowed at the rate of 109.5MMscf/d.

Zawtika-3 was drilled to a depth of 2,274m and encountered hydrocarbons in eight zones. It flowed at the rate of 26.7MMscf/d. Zawtika-4 flowed at the rate of 71.1MMscf/d from two zones. It was drilled in May 2007 to a depth of 2,390m.

Zawtika-5 encountered seven natural gas zones and flowed at the rate of 38.36MMscf/d. In 2010, PTTEP drilled two appraisal wells and one exploration well.

Zawtika project development details

PTTEP submitted the field development plan for the project to MOGE in the last quarter of 2011. The plan was approved in February 2011. Detailed engineering and construction work for the project was completed in the third quarter of 2013.

The project is being developed in phases. The first, Phase-1A, included the installation of the ZPQ processing platform integrated with a living quarters module, bridged-link wellhead platform WP1 and two remote wellhead platforms, WP2 and WP3.

It also included the installation of related intra-field sealines, offshore and onshore gas export pipelines, an onshore operating centre (ZOC), block valves ZBV1 and ZBV2, and a metering station. The subsea pipelines are 21km long with an 18in diameter.

Phase 1B of the project included the engineering, design, construction and installation (EPCI) of four wellhead platforms and the laying of four submarine pipelines.

Phase 1C included the engineering, procurement, construction and installation of wellhead platforms, pipelines and tie-ins, brownfield modifications of existing platforms and the installation of telecommunication and control systems integrated into existing facilities.

The fourth phase of the project, 1D, includes the installation of eight remote wellhead platforms, the drilling of eight new remote extraction wells, ZWP12 to ZWP19, in addition to associated pipelines with two pipeline end manifolds.

80% of the natural gas produced is exported to Thailand through a 28-in-diameter, 300-km-long pipeline. 230km of the pipeline is laid offshore, while the remaining 70km is onshore.

Infrastructure of PTTEP’s project

The three wellhead platforms and jackets weigh between 7,000t and 8,000t. They are installed at a water depth of 130m to 150m.

The processing facility includes topsides weighing 15,000t. The jacket of the topsides includes 20,000t piles. The processing facility also includes living quarters, with an accommodation capacity for 128 persons, and a 100m flare boom. It is a bridge connected to one of the wellhead platforms.

Contracts awarded for the gas fields

Vietnamese-Russian joint venture company Vietsovpetro is responsible for the construction of jackets for ZWP 12 and ZWP 15 platforms for Phase 1D.

Sarens, a heavy-lifting and engineered transport company, was subcontracted by Vietsovpetro to assist in the loading of the ZWP12 and ZP15 jackets.

Construction company COOEC was contracted for the construction of four platforms of Phase 1B. The company subcontracted Nautec, an ultra-high-performance concrete and composites (UHPC) producer, to provide grouting services for Phase IB. Nautec was also involved in Phase 1C of the Zawtika project.

Oil and gas platforms construction company PT Gunanusa Utama Fabricators (PTG) was awarded a $305m EPCI contract for two wellhead platforms, associated pipelines and tie-ins for Phase 1C of the project.

Sapura Energy was awarded a $205.96m subcontract by PTG to provide EPCI for the associated pipelines, and transportation and installation of the wellhead platforms along with brownfield modifications.

Chiwan Sembawang Engineering, an offshore engineering, procurement and construction services company, provided jackets and piles fabrication services for Phase 1C.

Larsen & Toubro Valdel Engineering was awarded a $200m contract to carry out the detailed engineering and design for the first phase of the project. Its contractual scope included the three wellhead platforms and related equipment.

Larsen & Toubro subcontracted EPConsult Energies to carry out safety, risk and reliability studies for the project. The platform installations were completed in the first quarter of 2013.

Offshore Construction Specialists, a marine construction management and engineering services provider, was subcontracted by Larsen & Toubro to provide project and construction management services.

SMOE, a subsidiary of Sembcorp Marine, was awarded a $600m contract for the engineering, design, construction and installation of the processing and accommodation platform for Phase 1A of the project.

Process Group was subcontracted by SMOE to supply a produced water treatment package and a fuel gas package.

China Petroleum Pipeline Bureau, a pipeline engineering survey design and consulting company, won a $180m contract for the onshore export pipeline and facilities.

Bredero Shaw, a unit of ShawCor, won a $600m pipeline coatings contract. Bredero Shaw provided anticorrosion coating and concrete weight coating for the pipelines.

FMC supplied restriction orifice plates and spools. Sound Environmental carried out noise and vibration studies for the development of the field.

Ace Winches, Austin Energy, GMS INTERNEER, LCS Cable Cranes, NLT Engineering, NRGTech Services, Offshore Oil Engineering, Offshore Weather Services, Oriental Construction, Seaowl, SR Group and UPCEM Engineering & Consultancy are some of the other contractors involved in the project.