青藏高原北部新生代陆相盆地石油地质条件及勘探前景

Petroleum Geology and exploration prospects in the Cenezoic continental basins in the northern part of the Qinghai-Xizang Plateau

青藏高原北部陆相盆地中烃源岩发育层位包括始新统风火山组、渐新统雅西措组和中新统五道梁组。古近系雅西措组烃源岩,特别是灰岩属于中好烃源岩范畴,有机质类型较好,且烃源岩主体处于成熟阶段,是藏北高原新生代陆相盆地主力烃源岩的发育层位。陆相盆地储集岩较发育,储层较丰富,发育层位包括风火山组和雅西措组,其中雅西措组是储层主力分布层位。对测区分析数据表明:通天河盆地具备一定规模的生油岩厚度,而且有机质丰度为沱沱河地区最高,表明其勘探前景较好。

The source rocks in the Cenezoic continental basins in the northern part of the Qinghai-Xizang Plateau consist of the Eocene Fenghuoshan Formation, Oligocene Yaxico Formation and Miocene Wudoaliang Formation. The source rocks especially the limestones from the Oligocene Yaxico Formation occurs as the main horizons of source rocks in the study area due to moderate to good oil potential, good types and maturation of organic matter. The reservoir rocks dominantly abound in the Eocene Fenghuoshan Formation and Oligocene Yaxico Formation. The results of research in this study have revealed that the Tongtian River Basin may have good petroleum potential due to greater thickness of source rocks and maximum contents of organic matter in the Tuotuo River Basin.