柴达木盆地狮子沟地区中深层裂缝性油藏

狮子沟构造位于柴达木盆地西部茫崖坳限，毗邻阿尔金斜坡，属于狮子沟－油砂山构造带，走向北北西－北西西（见图1），地面构造为南陡北缓的背斜，轴线长25km，宽7．8km，构造面积164．3km^2。1957－1977年探明狮子沟构造浅层（N2^1-N1 ,即下油砂山组－上干柴沟组）细－含砾砂岩油藏；1977－1985年发现中深层（N1－E1＋2，即上干柴沟组－路乐河组）裂缝性油气藏；1985年以后进入滚动勘探开发阶段。

Middle-deep fractured oil reservoir of Shizigou area in Qaidam basin

The Sh izigou structure is located in the Shizigou Youshashan structural belt of Mangy a depression of Qaidam basin. Source rocks and reservoir rocks in middle deep b ed, which is called Upper Ganchaigou lulehe Formation are in the same bed, wher e, fractured reservoirs have the oil generation and accumulation in the same for mation. Oil well productivity is very different. Main reservoirs are fracture p ore or pore fracture lacustrine carbonates. The reservoir pore space can be div ided into three levels: Macro fractures and vugs, obvious fractures and pores an d micro fractures and pores. They are mainly formed during late Himalayan moveme nt and neotectonic movement (Neogene Holocene). The development level of fractu res and vugs depends on lithology, tectonic stress and the forming time of disso lved pore space. The source and sealing conditions in middle deep formation are fine. The hydrocarbon enrichment is mainly controlled by the development level of fractured reservoir, forming time of reservoir pore space and trapping and se aling conditions. Many middle deep fractured reservoirs will be discovered in e astern Mangya depression. Further study should be done in palaeotectonic stress field in order to predict the fractures and vugs.