印度尼西亚Seram岛东部地区油源条件

印度尼西亚Seram岛东部油气显示活跃,已发现Bula油田和Oseil油田.BT-1 井、EN-1 井、BPM-26 井原油密度0.9～0.95 g/cm3,含蜡量较低,含硫量1.41%～2.69%,具有海相原油特征.原油族组分、碳同位素组成及正构烷烃、异构烷烃、甾萜烷等生物标志物分析进一步表明原油具有相似的海相碳酸盐岩来源.三叠系-侏罗系Saman-Saman层碳酸盐岩是由层状灰质泥灰岩和放射虫泥岩构成的海相石灰岩沉积,是该区的主要生油层系,Kobisonlah地区和Dawang Masiwang地区是两个最大的生油中心.原油成熟度分析表明该区存在两期油气生成与运移,生成的油气沿逆冲断层和不整合面运移,不同冲断块具有不同的油气来源,已发现的Oseil油田的低成熟度原油来自逆冲块中较浅的Saman-Saman层,而Bula油田的高成熟度原油来邻近的逆冲块中较深的Saman-Saman层.图7表2参16

Oil resource of East Seram Island, Indonesia

Shows of abundant oil and gas including Bula oilfield and Oseil oilfield have been found in east Seram Island. The oil densities of wells BT-1, EN-1 and BPM-26 are 0.9-0.95 g/cm3, and their sulfur contents are 1.41% -2.69%. Analyses of group composition, carbon isotopic composition and biomarkers of crude oils reveal that the oils came from similar source marine carbonates. The Tertiary-Jurassic Saman-Saman marine marlite is the most likely source rock. Kobisonlah area and Dawang Masiwang area are two biggest oil generating centers. Oil maturity shows that two stages of oil generation and migration happened in this area. The generated oil migrated along thrusts and unconformities. Different thrust blocks had different oil sources. The discovered Oseil low maturity oil came from shallow Saman-Saman carbonates, while the Bula high maturity oil came from deeper Saman-Saman carbonates. The oil resource condition of the Seram Island is favorable.