印度河扇水道堤岸外侧更新世沉积物波发育特征与形成过程分析  

Analysis on characteristics and formation process of sediment waves on the Pleistocene channel levee backslope of Indus fan

作　　者：浩克 纪友亮[1] 张胜久 刘炎鑫 Khurram Shahzad Saad Ahmed Mashwani 刘笑语 姜燕 Ehsan ul Haq;Ji You-Liang;Zhang Sheng-Jiu;Liu Yan-Xin;Khurram Shahzad;Saad Ahmed Mashwani;Liu Xiao-Yu;Jiang Yan(State Key Laboratory of Petroleum Resource and Prospecting,College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;Institut für Geologie,Universität Hamburg,Hamburg,Germany;Department of Earth&Environmental Sciences,Hazara University Mansehra,Khyber Pakhtunkhwa 21300,Pakistan;Engineering Technology Research Institute of Huabei Oilfield Company,Petro China,Hebei Renqiu 062550,China)

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,地球科学学院,北京102249 [2]汉堡大学地质研究所,德国汉堡 [3]哈扎拉大学曼塞拉分校地球与环境科学系,巴基斯坦开伯尔-普赫图赫瓦省21300 [4]中国石油华北油田工程技术研究院,河北任丘062550

出　　处：《古地理学报》2022年第2期389-404,共16页Journal of Palaeogeography：Chinese Edition

基　　金：国家自然科学基金项目(编号:42072115,41672098)资助。

摘　　要：印度河扇更新世发育的沉积物波结构复杂、形态多样,其形成过程的认识程度低。本次研究通过高分辨率地震数据和地震解释技术,研究了印度河扇沉积物波的波长、形态、波峰变化等形态特征;阐述了沉积物波与沉积物变形特征的差异、识别了两者的区分标志;总结了水道堤岸斜坡和区域斜坡上沉积物波的分布规律;在此基础上,讨论了沉积物波的形成机理和控制因素,分析了沉积物波的形成过程,并建立了印度河扇沉积物波的形成模式。研究表明:(1)研究区沉积物波波长平均为486.84 m,最大1473 m;波高在10~60 m之间,平均30 m。(2)沉积物波的形态有对称型和非对称型,其迁移方式有上坡迁移型、加积型和下坡迁移型;沉积物波主要发育在水道堤岸的斜坡上,在区域斜坡上也发育少量的沉积物波,这2种沉积物波波脊的走向差异很大,水道堤岸斜坡上的沉积物波主要分布于水道凹岸堤岸的外侧,距离水道越远其规模(波长、波高)越小,波脊走向近于NE-SW方向,与水道的走向平行或斜交;区域斜坡上的沉积物波波脊的走向多为NW-SE向,平行于区域斜坡的走向,离源区越远规模越大。(3)水道堤岸斜坡上的沉积物波是由水道型浊流在离心力的作用下,溢出水道的凹岸,在堤岸外侧的斜坡上沉积形成的,堤岸斜坡的角度对沉积物波的发育规模影响不大,浊流的强度和输沙量对其规模影响大;区域斜坡上发育的沉积物波是由顺坡而下的非水道化的浊流沉积形成;滑塌变形造成的起伏地貌以及早期沉积物波的存在,也都影响了后期沉积物波的发育。Architecture of the turbidity current sediment waves exhibit intricate morphologies and patterns on Indus fan channel levee back.The sediment waves are present on the channel levee of Pleisto-cene age in the study area,and their formation process is poorly understood.Through high-resolution seis-mic data and seismic interpretation technology,the difference between sediment wave and sediment de-formation characteristics is expounded,and the distinguishing mark of the two sediments are summarized;the distribution law of sediment wave on the slope of the channel levee backslope and the regional slope is summarized;on this basis,the formation mechanism of the sediment wave is discussed,and the control-ling factors and the formation process of sediment wave are analyzed.At last,the formation mode of sedi-ment wave in Indus fan are established.The research result shows that:(1)The average wave length of the sediment wave in the study area is 486.84 m,and the maximum wavelength is 1473 m;the sediment wave height is between 10 m and 60 m,with an average of 30 m.(2)The morphology of sediment wave is symmetric and asymmetric,and its migration pattern include upslope migration type,aggregative type and downslope migration type.the sediment wave is mainly developed on the channel levee back,a small a-mount of sediment waves are also developed on the regional slope.The trends of these two types of sediment waves are very different.The sediment waves on the channel levee backslope are mainly distributed on the levee backslope in concave bank of the channel.The farther away from the channel,the smaller the di-mension of sediment waves(wave length and wave height),and its trend is close to the NE-SW direc-tion,parallel or oblique to the channel trend.The trend of sediment waves on the regional slope is mostly NW-SE,which is parallel to the trend of the regional slope,and its dimension is larger the farther away from the source area.(3)The sediment waves on the channel levee backslope is formed by the channel-type turbidity curre

关 键 词：沉积物波 水道堤岸斜坡 浊流 更新世 印度河扇 

分 类 号：P512.2[天文地球—地质学]