摘要
为了揭示黄骅坳陷孔店地区馆陶组沉积演化规律,本文以井和地震资料划分出的沉积层序及体系域为等时地层单元对相应的地震资料进行90°相位转化及地层切片处理,结合单井相分析结果刻画并解释沉积体系的平面展布特征并建立了孔店地区河流沉积体系演化模式.认为馆陶组为一完整三级层序,可划分为低位、水侵和高位3个体系域,低位和高位体系域发育辫状河沉积,水侵体系域发育曲流河体系,馆陶组经历了辫状河-曲流河-辫状河的演化过程.研究结果表明:辫状沉积体系中厚层砂体垂向频繁叠置,厚度可达70m,平面上大面积展布,泛滥平原沉积发育较差,地层含砂率大于70%;曲流河道及边滩砂体呈孤立状被厚层泛滥平原泥岩包裹,平面上曲流河沉积分布于大面积泛滥平原内,泛滥平原泥岩占比为48.5%.可容空间和古气候控制了基准面变化进而控制了河流沉积体系展布模式,可容空间相对较低,气候相对潮湿时,发育大范围辫状河沉积体系,基准面迅速上升时期,可容空间迅速增加且气候相对干燥,更有利于曲流河的发育.
To reveal the sedimentary evolution law of the Guantao formation in Kongdian area of Huanghua depression,the paper divided sedimentary sequence and system tract as isochronous stratigraphic units based on well and seismic data and also dealt with seismic data by technology of 90°phasing and stratal slicing.Combined with the analysis of single well facies,the plane distribution characteristics of sedimentary system have been described and interpreted and the evolution model of fluvial sedimentary system in Kongdian area has also been established.The results show that Guantao formation is a whole third-order sedimentary sequence which could be divided into three system tracts：LST,TST and HST.The braided river deposits mainly develop in LST and HST and the meandering river deposits develop in TST.Guantaoformation has experienced the evolutionary stages from braided river through meandering river to braided river.The channel sand bodies are superposed vertically with thickness up to 70 min the braided river deposits.The central bars and braided rivers are extensively distributed and the floodplain sediments are poorly developed with a high sand ratio greater than 70%.For the meandering channel and beach,the sand bodies are isolated and wrapped up by floodplain mudstone and the meandering river deposits are distributed in the wide floodplain on the plane.The proportion of floodplain mudstone in the meandering river deposits is 48.5%.Furthermore,distribution model of the fluvial sedimentary system is controlled by base level change which is constrained by the combined action of accommodation and paleoclimate.The braided river deposits develop extensively under small accommodation space and humid climate.However,the rapidly rising accommodation space and the dry climate are more conducive to the development of meandering river when the base level rises rapidly.
作者
刘海
林承焰
张宪国
栗宝鹃
LIU Hai;LIN Chengyan;ZHANG Xianguo;LI Baojuan(School of Geoscienees, Chinese University of Petroleum, Qingdao, Shandong 266580, China;CNOOC EnerTech-Safety ＆ Enviromental Protection Co, Tianjin 300450, China)
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2018年第3期549-561,共13页
Journal of China University of Mining & Technology
基金
国家自然科学基金项目(41672129)
关键词
沉积特征
层序地层
地层切片
沉积模式
黄骅坳陷
sedimentological characteristics
sequence stratigraphys
stratal slice
sedimentary model
Huanghua depression
