断层几何学特征及对浊积岩的控制作用

为解释断层下降盘浊积砂体横向不均一的控制机理，从河125断层几何特征入手，剖析了断层形态与浊积砂体的关系，发现弧形断裂平行于断层走向剖面上为断槽、断脊组合；在垂直于断层走向剖面上断层可分为竖滑段、倾滑段和平滑段三段。生长指数规律为弧中大于弧翼；H/L指数为弧中小于弧翼。断裂的几何学特征与动力学、运动学特征具有相关性，断裂不同位置几何学特征的不同反映了断裂动力学、运动学特征的差异。断层对浊积岩具有重要的控制作用：弧中对应浊积扇最发育区，弧翼为不同浊积扇的分界线；断槽为浊积砂体的补给通道；断脊为扇体不同补给区的分水岭，形成了典型的弧扇对应现象。

Geometry Characteristics of the Fault and the Control over Turbidite

Research of the characteristic of fault He125 is conducted to dissect the relationship between characteristics of the fault and turbidite for explaining the mechanism controlling the nonisotropy sandstone turbidite of downthrow block. The arcuate fault is the combination of fault trough and fault ridge, it is found from the section that is parallel to the arcuate, the fault can be separately divided into three parts, vertical-slip part, dip-slip part and horizontal-slip part from the section that is perpendicular to the fault. The law of the growth index is that arc center is greater than arc flank; and the ratio of H/L (height/length) is that arc flank is greater than arc center. There are some relations between the geometry characteristic of the arc and its dynamic and kinematic characteristic. The different geometry characteristic of the different localities shows the difference of their dynamic and kinematic characteristic. Geometry characteristics of the fault system controlls the distribution of turbidite, on surface, the arc center corresponds the turbidite fan, the arc flank is the boundary of these turbidite fans, the fault trough is the recharging path of the turbidite fan and the fault ridge is the watershed lines of the different recharging areas. Vertically, the lower dip-slip part corresponds far-bank turbidite, and the middle and upper parts correspond slump turbidite fan, which forms a typical corresponding phenomenon of the arc and fan.