柴达木盆地西部南区同沉积逆断层控制下的输导系统特征及其勘探意义

Characteristics and exploration significance of the hydrocarbon migration system controlled by the synsedimentary reverse faults in the southwest area of Qaidam Basin

针对柴达木盆地西部南区(简称柴西南区)独特的地质条件和成藏特征,提出了生长逆断层控制下的"F"型输导系统.通过分析生长逆断层对构造、沉积及储层物性的控制作用,阐述了此类输导系统形成机制、组成特征及其控油意义.认为"F"型输导系统主要由生长逆断层和侧向展布的砂体构成,砂体位于逆断层的上盘,紧靠断层发育;生长逆断层是主要的输导体,油气以垂向运移为主,侧向运移为辅."F"型输导系统及"F"型运移模式是柴西南区生长逆断层控制的构造油气藏成藏的主要通道和运移方式.

According to the study on the geological conditions and hydrocarbon accumulation characteristics in the southwest of Qaidam Basin,it is presented that the hydrocarbon migration system in this area is the 'F' -type system controlled by growth thrusts.The control effects of the growth thrusts on the structures,deposits and reservoir property are analyzed,according to which the formation mechanism,compositional characteristics and hydrocarbon-controlling effect of this type of hydrocarbon migration systems are described.It is held that this type of hydrocarbon migration systems consists of growth thrusts and lateral sandbodies,the sandbodies are developed abut against the growth thrusts and locate in the top wall of the growth thrusts.The growth thrusts are main carrying body,in which the main migration of hydrocarbon is vertical,and the secondary migration is lateral.The 'F' type of migration mode is main migration mode in this area.