青西油田下白垩统裂缝特征及其成因

岩心和成像测井等资料表明，酒西盆地青南凹陷下白垩统发育北东-南西走向和北西-南东走向的一对共轭切层缝，它们是青西油田下白垩统油气藏储集层中的重要裂缝类型。通过对青西油田下白垩统沉积特征、成岩作用和构造应力场的综合分析，认为在窟窿山冲断片北部的窿7-窿4 井区以及柳沟庄冲断片，发育大量北东-南西向切层缝，其数量明显多于北西-南东向构造切层缝；在窟窿山冲断片南部的窿8-窿10 井区，发育大量北西-南东向切层缝，与北东-南西向构造切层缝相比，前者在数量上占主导。这些占据主导地位的切层缝，其雏型是差异压实作用形成的，在构造应力作用下进一步发育和定型。

Fractural Characteristic and Genesis of Lower Crataceous in Qingxi Oilfield

In Lower Crataceous in Qingxi sag of Jiuxi basin occurs a couple of NE-SW and NW-SE trending conjugated bedding-dissected fractures based on core and imaging logging data. The fractures are the major types in Lower Crataceous fractured reservoir in Qingxi sag. According to comprehensive analysis of Lower Crataceous sedimentation and diagenesis and tectonic stress field, a great deal of NE-SW trending bedding-dissected fractures occur in Well Area Long-7 to Long-4 of Kulongshan thrust section and Liugouzhuang thrust section, while in Well Area Long-8 to Long-10 NW-SE trending such fractures are dominant, but the number of the former is predominant. These dominant fractures are formed by initial compaction followed by tectonic stress action.