Exploration and development of Rang Dong oil field in Block 15-2, offshore Vietnam

摘要

In october 1992, production sharing contract for Block 15-2, offshor Vietnam was concluded between Mitsubishi Oil Co., Ltd. and Vietnam Oil and Gas Corporation(Petrovietnam), and the license was assigned to Japan Vietnam Petroleum Co., Ltd.(JVPC) for the implementation of exploration and development. Block 15-2 locates in Mekong Basin, which has a granite basement overlaid mainly with thick Tertiary clastics and includes Back Ho field, the largest oil field in Vietnam producing since 1986. Based on the geological and geophysical studies, firstexploration well was drilled in Rang Dong prospect and confirmed the significant oil flow over 14,000 bbl/day from the granite drilling,"Commerical Discovery Declaration"was made in June 1996. Target reservoir is the granitic basement fractured reservoir, with very unique features mainly developed by tectonic. Detection of the f racture distribution in the basement and evaluation of its extent. Meanwhile there still exist lots of uncertainty in quantitative evaluation of the fracture. Due to such uncertainty, the norhern part of the field was decided to develop as first phase development, prior to entering into full-field development. Being high pour point about 30 deg C,produced oil is separated to liquid and associated gas on Wellhead Platform, and the separated fluid is then transported to a tanker converted EPSO (floating, process, storage and offloading system)for exporting oil to shuttle tanke, instead of to onshore via pipeline. 18 months after commencement of the fabricatin of production facilities, first oil production was achieved on August 30, 1998, with six pre-drilled production well. As of December 1999, total nine production wells are on stream. JVPC is planning to conduct further appraisal works in the remaining southern part of the Rang Dong field for future development.