系统分析了柴达木盆地北缘构造变形及断裂发育特征,对构造样式进行了细化,研究了不同构造样式的断层侧、垂向封闭特征及对油气运移、保存的控制作用.柴达木盆地北缘构造变形主要以逆冲走滑为主,以上、下干柴沟组地层为界划分出3套断裂系统,发育基底卷入型、厚(薄)—薄(厚)叠加型2种构造样式.柴达木盆地北缘断层侧向封闭类型为泥岩涂抹封闭、层状硅酸盐—框架断层岩封闭和碎裂岩封闭3类,起封闭作用的为泥岩涂抹封闭和层状硅酸盐—框架断层岩封闭.厚—薄叠加型构造断层侧向封闭性要好于基底卷入型构造断层侧向封闭性.由于下干柴沟组(E3)和上干柴沟组(N1)塑性地层存在,导致柴北缘断层垂向封闭性较强,有利于油气富集在此2套地层之下.%The structural deformation and fault developed characteristics in the northern margin of Qaidam Basin are systematically analyzed. And furthermore, the structural styles are finely divided; the lateral & vertical sealing characteristics of the faults with various structural forms and the controlling actions on the hydrocarbon migration and preservation are studied. The deformation is mainly characterized by thrust and strike slip, and moreover composed of 3 sets of fault systems taking Upper and Lower Ganchaigou Formations as interfaces, where 2 types of structural forms ( basement-involved and thickness-thinness interstacked) are developed. There are 3 styles of lateral tightness in the faults there including mudstone coating, layered silicate frame and fractured rocks, the former two mainly play the sealing role. The laterally tight property of the interstacked form is better than that of the basement type. Due to the existence of plastic formation of Lower ( E3) and Upper ( N1) Ganchaigou Formations, the vertical tightness of the faults in this region is pretty stronger and furthermore it is beneficial for oil and gas accumulation in these two sets of formations.
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