Release: CityView: Simenggaris concession prospect montague
Monday, January 23 2006 - 07:58 AM WIB
January 23, 2006 - City View Corporation Limited (?CityView?) announces the following summary of a prospect montage prepared by the Medco Simenggaris-Pertamina JOB and received from its Joint Venture partner and operating shareholder, PT Medco Energi Internasional TBK (?Medco?):
SESAYAP B1 WELL
Sesayap-B1 is an exploration well and is located in the south-western part of the Simenggaris block. It lies in the Bangkudulis - Sembakung half-graben area of the western part of the Tarakan sub-basin.
More specifically, it is located just north of the Sesayap River, north of Tiga island and 2.9 kms north of Bangkudulis Kecil island. This is about 30 kms northwest of Tarakan island. It is approximately 4.3 kms south of the Sesayap-A1 discovery; 19 Kms north-northeast of the Bangkudulis oil field.
The Sesayap-A1 well encountered multiple sandstone reservoirs within the Meliat and Tabul formations. They flowed at: 28.4 MMSCFD and also included condensate. This was from 8 DSTs. The Bangkudulis-l well flowed at 5996 BOPD from 5 DSTs also within multiple sandstone layers. These sandstone layers are in distributory channels
The primary targets of the Sesayap-B1 well are sandstone reservoirs within the Tabul and Meliat formations that are proven to have a significant hydrocarbon potential as is displayed by the Sesayap-A1 well logs.
The drilling will also establish the Santul and Naintupo formation sandstone reservoirs as the secondary target, as indicated by shows from the Sesayap-A1 well.
Sesayap-B1 will be drilled at SP 400, seismic line 1237 G 78 location. This location has good channel sandstone development and a closure of Tabul and Meliat formations.
Sesayap-B1 well is expected to penetrate the Top Santul at 660ft; the Top Tabul at 1600ft; and Top Meliat at 25l0ft; and Top Naintupo at 3450ft. TD will be at 6000ft within the Naintupo formation.
HYDROCARBON RESOURCES
The Sesayap-B1 structure area is expected to contain resources estimated at 9 MMBO and 381 BCFG from the Meliat and Tabul reservoirs. The estimated chance of success is 30%.
RECOMMENDATION TO DRILL SESAYAP-B1
The recommendation to drill the well has been based on the analysis of the favourable results from adjacent wells (Sesayap-A1) and testing. Porosity logs indicate a range of 22-32%. The Meliat sandstones are the main producing reservoirs in the Bangkudulis field. Several channel sandstone lobes indicated by seismic are likely to be well developed across the Sesayap-B1 prospect.
Multiple sandstone reservoirs of upper to lower delta plain, deposited in braided channels, in the Tabul and Meliat formations were proven to be productive in Sesayap-A1. Sesayap-E1 and Bangkudulis-1 wells.
GEOLOGICAL AND STRUCTURAL SETTING
Sesayap-B1 is situated in the Sembakung Bangkudulis half graben area in the western part of the Tarakan sub-basin. Its structure is interpreted as a roll-over anticline structure, bounded to north and south by faults from the Tabul and Meliat level.
The prospect lies at the central part of the Bangkudulis-Sesavap-A1 hydrocarbon trend. The Sesayap structure was formed by uplifting during Miocene-Pliocene tectonics and further compressed during the Upper Pliocene.
STRATIGRAPHY
The Sesayap-B1 prospect is 70 milliseconds higher than Sesayap-A1 at the Tabul level and 150 milliseconds lower than the Bangkudulis structure at the Meliat level.
The main potential source of hydrocarbons for the Simenggaris block is the organic rich shales and coals of the Meliat formation and, to a lesser extent, the Naintupo formation. Thermal maturity levels show that both shales are in the onset of maturity. The migration systems are both lateral running through the adjacent carrier beds and vertically along the older growth fault prior to Plio-Pleistocene compression.
The well should penetrate the Tarakan. Santul and Tabul formations at shallow depth. It is likely that the Tarakan formations have been eroded; therefore the intra-formation shales within lower Santul and upper-middle Tabul is expected to provide an excellent seal. Similarly, intra-formational shales in the Meliat will likely perform the same function.
It is anticipated that precautions need to be taken during drilling due to high gas readings. Moreover, it is possible that loss circulation may be encountered due to sandstone reservoir thickening (as occurred in Sesayap-A1). Thus, it is suggested that close attention be paid to mud weight considerations.(end of release)