柴达木盆地东部地区中生界不整合与油气成藏的关系

地层不整合对油气成藏具有重要作用。柴达木盆地经历了多次构造运动的改造，形成了多个不整合。在测井曲线分析的基础上，结合岩心观察、不整合成因机制及地震反射特征分析，对该区不整合与油气成藏的关系进行了研究。结果表明，柴达木盆地东部地区中生界不整合可划分为削截不整合、超覆不整合、断褶不整合和平行不整合4种类型。受不整合的控制，油气沿不整合面运移，风化剥蚀程度的不均一性使不整合具有典型的层状结构，将不整合面上、下划分为底砾岩、风化粘土层和半风化淋滤带。在纵向上，不整合的分层结构可构成油气运移的双重通道，为油气聚集提供良好的储集空间和圈闭条件。不同的不整合剖面类型可以形成不同的油气成藏模式。

Relationship between unconformity and hydrocarbon accumulation in the Mesozoic of eastern Qaidam Basin

Stratigraphic unconformity plays an important role in hydrocarbon accumulation. Qaidam Basin underwent multistage tectonic movements and formed several unconformities. Based on the analysis of logging curve, core observation, unconformity genesis mechanisms and seismic reflection characters, the relationship between the unconformity and hydrocarbon accumulation was studied. The results show the unconformities of eastern Qaidam Basin can be divided into four kinds such as truncation unconformity, onlay unconformity, fault-fold unconformity and parallel unconformity. Unconformity models control oil-gas migration along the unconformity surfaces. Laminar textures due to uneven weathering and denuda- tion processes are typical of unconformities, and the unconformity surfaces in vertices are divided into three parts including basal conglomerate, weathering clay stone and semi-weathering leached zone. Structure of unconformities on vertical zonation not only is the double pathways for oil and gas migration, but accumulation. The different types of unconformity show different also provides reservoir space and trap condition for oil-gas oil-gas reservoir-forming patterns.