东濮凹陷南部沙三中段构造调节带对沉积体系的控制作用

Accommodation Zones and Their Controls on Depositional System in the Middle of Third Member of Shahejie Formation,South of Dongpu Sag

东濮凹陷是一个由其东部的兰聊断层拉伸活动造成的新生代伸展断陷盆地。构造调节带是东濮凹陷南部发育的主要变换构造类型。根据断层的组合特点与断距变化,归纳出4种倾向类型、3类叠覆类型,并根据其组合关系细分出11种构造调节带类型,且在东濮凹陷南部识别出其中的8种类型。东濮凹陷南部的构造调节带对沉积体系的发育有控制作用:西部斜坡带发育的同向调节带可作为物源通道,发育大面积的三角洲沉积体系;兰聊断裂带下降盘中的断鼻调节带也可作为物源出口,发育扇三角洲前缘沉积体系;中央隆起带中的背向调节带起分隔次级汇水盆地的作用。东濮凹陷南部的调节带形成机制与兰聊断裂的几何学与运动学特征有关,兰聊断裂的断面形态、活动差异及走滑运动分量是调节带形成的主控动力学机制。

Dongpu sag is a Cenozoic extend-faulted basin formed by extension contributed by Lanliao fault.Accommodation zones are main types of transfer zones developed in south of Dongpu sag.Based on fault＇s configuration and displacement,four tendency types and three overlap types are summarized;moreover,eleven types of accommodation zones are confirmed,among which eight are found in south of Dongpu sag.Accommodation zones control the development of depositional systems in south of Dongpu sag： Synthetic accommodation zones formed in west slope can act as a sediment exit of large delta system;Fault-nose in degressive block of Lanliao fault can also play as an exit of relatively small fan delta system;Antithetic accommodation zones in central uplift zone,however,separate secondary catchment basins.The forming dynamics mechanism of accommodation zones is closely correlative with geometry and kinematics of Lanliao fault,whose cross section shape,displacement variation and strike-slip are the domain controlling factors.