With the 18th concession bid round, 14 additional exploration blocks were awarded, resulting in more petroleum exploration activities than in 2003, both onshore and offshore. These activities consisted of seismic activities and exploration drilling.
Taking place both offshore and onshore, seismic surveys were of the two-dimensional (2D) and three-dimensional (3D) types. The former covered 57 km and the latter covered an area of 2,294 sq. km.
Onshore, in Kamphaeng Phet, CNPCHK (Thailand) conducted 3D seismic surveys covering 103 sq. km. in Block L21/43, south of Bung Ya – Bung Muang Fields, to delineate additional petroleum structures to the west of Phitsanulok Basin.
Siam Moeco conducted 2D and 3D seismic surveys in Blocks L10/43 and L11/43, north of Sirikit Field, around Sukhothai and Phitsanulok. As of year-end 2004, a total of 57 km and 92 sq. km. had been covered respectively. This exploration program will continue through 2005.
In Phetchabun, Pacific Tiger Resources (Thailand) conducted 3D seismic surveys covering six sq. km. in Block L44/43, south of the Wichian Buri Field, but suspended operations due to the rainy season.
In the Gulf of Thailand, Chevron Offshore (Thailand) conducted 3D seismic surveys, which had by year-end chalked up 1,828 sq. km. in Block G4/43, west of Tantawan and Benchamas Fields. This exploration program will continue through 2005.
Pearl Oil (Thailand) conducted additional 3D seismic surveys covering 263 sq. km. of Jasmine Field and the vicinity in Block B5/27 to locate well platforms and identify additional petroleum structures in reserved areas around its existing production areas.
Geophysical Surveys in 2004
Exploration Drilling in 2004
* E5 N = E5 outside Nam Phong Area
A total of 284 wells were drilled through the year, of which 26 were exploration wells and 258 were development ones.
Exploration wells consisted of eight wildcats, 11 delineation and seven appraisal wells described below.
In Surat Thani, SVS Energy Resources found shallow coal at its Plai Khlong-1 exploration wells intended to find natural gas in Block L71/43, around Khien Sa Basin. Thin layers of coal and traces of natural gas were detected.
In Phetchabun, Pacific Tiger Resources (Thailand) drilled Wichian Buri N-7 in Block L44/43. Based on drilling logs, crude oil was to be found in the F-Sand formation, but since production tests yielded only water, it was suspected that the highly viscous oil could not come up to the surface.
Amerada Hess (Thailand) drilled the Phu Horm-4 and Phu Horm-5 appraisal wells at the Phu Horm structure in Exploration Blocks EU1 and E5N in Udon Thani and Khon Kaen. The company used the underbalanced drilling technique, which had worked well at Phu Horm-3, where natural gas was discovered in fractured limestone. Production tests at both wells yielded flow rates of 40 and 30 MMcfd respectively. The company plans to produce natural gas from Phu Horm Field, pipe it to Nam Phong Power Plant, Khon Kaen, and substitute a major portion of the Nam Phong gas, which had dwindled in volume so much that its electricity generating efficiency had deteriorated.
In the Gulf of Thailand, PTT Exploration and Production drilled more delineation wells in Blocks B14A and B15A for Arthit Field at Arthit-15-14X, Arthit-14-7, Arthit-14-8X, Arthit-15-3S, Arthit-15-11, Arthit-15-13, Arthit-15-13A, and Arthit-15-15. All these wells encountered natural gas. In addition, the company undertook more delineation drilling in the vicinity of Bongkot Field, namely BK-DEL-23 and BK-DEL-24 wells in Block B16. Both were classified as gas wells.
Unocal Thailand drilled three delineation wells at the South Gomin structure in Block B13, namely South Gomin-02, South Gomin-03, and South Gomin-04, all of which struck gas. Unocal made a similar discovery at Satun-32 at the Satun structure, and struck both gas and oil at North Kung-1 and Ranong East-01 wells in Block B10.
Chevron Offshore (Thailand) drilled two appraisal wells in Block B8/32, namely Chaba-3 (striking both gas and oil) and Benchamas North-5 (dry hole), and drilled two exploration wells in Block G4/43, namely Lanta-1 and Lanta-2, to the west of Benchamas Field. Both struck gas and oil.
Pearl Oil (Thailand) drilled two exploration wells in Block B11/38, namely Chang Ton-1 and Chang Thai-1, but struck no petroleum there.