天山南亚肯地区天然气成藏条件及成藏模式

NATURAL GAS RESERVOIRING CONDITIONS AND RESERVOIRING PATTERNS IN YAKEN REGION OF THE SOUTH OF TIANSHAN MOUNTAINS

亚肯地区是天山南天然气勘探的重点地区。该区气藏气体成分主要为凝析气,气藏分布受与断裂伴生的构造或构造带控制。成藏条件分析表明,该区油源丰富,发育多套储盖组合,多种类型圈闭发育且成排成带分布,成藏地质条件配置较好,具有形成大中型油气田的有利条件。在此基础上,提出了该区天然气成藏的2种模式:即天然气沿不整合面、断层和砂体长距离运移构造圈闭成藏模式,天然气沿砂体侧向运移地层超覆圈闭成藏模式。

YaKen Region, an important region for natural gas exploration,is located in the south of Tianshan Mountains. Structures or structural belts accompanying with the fractures control the distribution of the gas reservoir, whose main composition is condensate gas. The analysis of reservoiring conditions suggests that this area is likely to be large or medium-sized oil gas field, with abundant oil-sources, many well developed series of reservoir and cap rock combination and traps distributing in lines and belts, and good reservoir geologic conditions. Based on these researches, the authors proposed two kinds of natural gas reservoiring patterns. The first pattern is the structural traps formed by the long distance migration of natural gas along the unconformity surfaces, fractures and sand bodies. The other one is stratigraphic overlap trap formed by the lateral migration of natural gas along sand bodies.