双河扇三角洲构造背景及沉积特征研究
Structural Setting and Depositional Features of the Shuanghe Fan Delta
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摘要: 双河扇三角洲为高建设型的扇三角洲复合体,由于物源、流向比较稳定,继承性和规律性较强,总体表现为下大上小的迭瓦状退复式沉积。该三角洲复合体由100多个沉积单元组成。每一个扇三角洲单元,可分出平原相,前缘相。前缘相又可进一步细分为水下分流河道亚相,前缘砂亚相和边缘席状砂亚相。前缘相向外,则为前扇三角洲相。因此,它具有陆上平原、过渡带及水下环境三者在纵横向上的连续性建造。Abstract: The Shuanghe fan delta is a high constructive fan delta complex with relatively strong inheritance and regularity due to the stable source and flow direction and appears as a enlarging-downward overlapping deposit.The delta complex is composed of over100sedimentary units each of which can be divided into a plain facies and a frontier facies.The frontier facies can be subdivided into underwater distributary channel subfacies,frontier sand subfacies and marginal sand sheet subfacies.Further out from the frontier facies exists pre-fan delta facies.It is a construc-tion where continental plain,transitional zone and underwater environment are continuous vertically and laterally.