苏北盆地海安凹陷构造样式及圈闭类型

Structural style and trap type in Haian Sag, Subei Basin

以铲式正断层为主，海安凹陷具有伸展断陷盆地的地堑-地垒系统的地质结构特征。不同类型的正断层以不同的方式组合在一起构成丰富多彩的构造样式。根据成因的不同，将海安凹陷构造样式划分为两种类型：伸展构造样式和走滑构造样式。海安凹陷的圈闭主要为断块和断鼻。根据圈闭的平面、剖面形态特征及断层、地层组合方式，可将断层圈闭划分为屋脊式断鼻圈闭（反向断鼻圈闭）、顺向断层断鼻圈闭、弧形断层断块圈闭、地垒式断块圈闭、阶梯式断块圈闭、地堑式断块圈闭和变换构造圈闭等7种类型。

Character of geologic stucture is graben-horst system of extensional rift basin in Haian Sag, with listric normal faults. Different normal faults with different combination modes, lead to abundant structural styles. Based on their formation, structural styles in Haian Sag are divided into two types, i.e.extensional structural style and strike-slip stuctural style. The types of traps in Haian Sag are fault nose and fault block. According to plane and section character of traps and combination modes of faults and strata, there are seven kinds of traps： fastigium fault nose（antithetic fault nose）, synthetic fault nose, arc fault block, horst fault block, ladder fault block, garben fault block and transfer structural trap.