海拉尔盆地查干诺尔凹陷下白垩统层序地层格架及沉积体系研究

STUDY ON THE LOWER CRETACEOUS SEQUENCE STRATIGRAPHY AND DEPOSITIONAL SYSTEMS IN THE CHAGANNUOER DEPRESSION OF THE HAILAER BASIN

依据岩芯、测井、录井和地震资料,以层序地层学理论为指导对海拉尔盆地查干诺尔凹陷下白垩统的扎赉诺尔群进行层序地层划分。扎赉诺尔群可划分为1个超层序,形成于凹陷断陷发育期,自下而上可划分为5个三级层序(Sq1、Sq2、Sq3、Sq4、Sq5)。进而在层序框架内对沉积体系类型和时空展布特征进行了分析。凹陷主要发育冲积扇、扇三角洲、湖底扇、滨浅湖和半深—深湖沉积体系,并且层序地层格架对各沉积体系分布具有控制作用。

Based on the theories and methods of sequence stratigraphy,a sequence stratigraphic framework has been established for the Early Cretaceous rocks in the Chagannuoer Depression of the Hailaer Basin by using core,logging and 3-D seismic data.The Early Cretaceous Zhalainuoer Group is a super sequence,which can be divided into five third-order sequences(Sq1,Sq2,Sq3,Sq4,Sq5).The types of sedimentary system and distribution characteristics were analyzed in the sequence stratigraphic frame.Alluvial fan,fan delta,sublacustrine fan,shore-shallow lacustrine and deep lacustrine facies were recognized in Chagannuoer Depression.The distribution of these depositional systems was controlled by the sequence development.