柴达木盆地油气地质特征与有利勘探领域

柴达木盆地是我国七大含油气盆地之一,具有较丰富的油气资源,勘探潜力与难度并存。该盆地经历了晚古生代、中生代和新生代3个成盆旋回,中生代断坳复合盆地形成了柴达木盆地北缘侏罗系油气系统,新生代大型走滑挤压盆地形成了柴达木盆地西部第三系油气系统和三湖第四系天然气系统,燕山和喜山2期强烈构造运动使柴北缘侏罗系油气系统高度复杂化,新生代单旋回古气候演化与多期构造运动使湖盆演化、烃源岩和沉积储层发育特征、成藏条件与油气分布规律变得十分特殊和复杂。认为应围绕柴西第三系富油凹陷和三湖第四系富气凹陷,加强石油和天然气勘探,同时加大柴北缘东段德令哈新区风险勘探力度,为实现战略突破创造条件。

PETROLEUM GEOLOGICAL CHARACTER AND FAVORABLE EXPLORATION DOMAINS OF QAIDAM BASIN

Qaidam basin, one of the seven largest oil-gas bearing basins of China, is abundance in petroleum reserve and exploration potential and difficulty are dual. The basin experienced three basinforming cycles of Neopaleozoic, Mesozoic and Cenozoic Eras. Mesozoic fault and depression compounding basin composed the northern margin Jurassic petroleum system and the Cenozoic large-scale strike-slip and compressional basins composed the Tertiary petroleum system of the western Qaidam basin and Quaternary petroleum system of Sanhu. The intense tectogenesis of Yanshan and Xishan made the Jurassic petroleum system of the northern Qaidam more complex. The monocycle paleoclimate evolution in Cenozoic Era and multi-tectonic movement made the lake-basin evolution, hydrocarbon source-rock, reservoir development, accumulation condition and petroleum distribution are more exceptive in character and complex in feature. In the future, the exploration will focus on the petroleum exploration in the Tertiary fuel-rich depression of the western Qaidam and Quaternary depression of Sanhu, at the same time, the risk exploration of Delingha, east part of the northern Qaidam, should be pay more attention to for further strategy breakthrough.