基于物理模拟的三角洲前缘横向砂坝发育过程及形成机理  

Development Process and Formation Mechanism of Transverse Sand Bar in Delta Front Based on Physical Simulation

作　　者：王昕 魏思源 吕奇奇[1] 代榕 呼焕 毕宇航 张丽雯 梁岩 张建坤 WANG Xin;WEI SiYuan;LÜQiQi;DAI Rong;HU Huan;BI YuHang;ZHANG LiWen;LIANG Yan;ZHANG JianKun(School of Geosciences,Yangtze University,Wuhan 430100,China;College of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China;School of Physics and Optoelectronic Engineering,Yangtze University,Jingzhou,Hubei 434023,China;East China University of Technology,Nanchang 330013,China)

机构地区：[1]长江大学地球科学学院,武汉430100 [2]中国地质大学(北京)能源学院,北京100083 [3]长江大学物理与光电工程学院,湖北荆州434023 [4]东华理工大学,南昌330013

出　　处：《沉积学报》2023年第3期818-827,共10页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目(42102170);长江大学大学生创新创业计划项目(Yz2020020);江西省自然科学基金项目(20202BAB204035)。

摘　　要：为探究波浪作用对三角洲前缘砂体的控制作用,并研究横向砂坝形成过程,利用物理模拟实验再现波浪作用下三角洲前缘砂体的发育过程。研究发现:波浪作用除了对三角洲河口沉积物影响外,还对已形成的三角洲前缘砂体有着侵蚀、改造的作用;受波浪、波生沿岸流及局部离岸流的影响,三角洲前缘砂体表面发育多期次平行于湖岸线展布的横向砂坝,其后部发育冲沟。沿岸流将波浪和河流带来的沉积物向砂坝两侧搬运沉积,使砂坝横向延伸;同时,波浪的强度、入射角度也决定了横向砂坝的规模及发育位置。经与鄂尔多斯盆地西南部长82三角洲沉积对比,反映出较好的耦合关系,表明该实验认识对波浪作用下三角洲前缘砂体发育样式研究有一定的指导意义。To explore the controlling influence of wave action on a delta front sand body and study the formation process of transverse sand bars,physical simulation experiments are conducted to reproduce the development of a delta front sand body subjected to wave action.The study found that wave action not only affected the delta estuarine sediments,but also eroded and transformed the delta front sand bodies that were formed.Under the influence of waves,of wave-generated coastal current and of local offshore current,transverse sand bars were developed parallel to the lake shoreline many times on the sand body surface of the delta front,and gullies were developed behind the sand bars.The coastal current transports and deposits the sediments carried by waves and rivers to both sides of the sand bar,extending the sand bar laterally.The strength and angle of incidence of the waves also determines the scale and location of any transverse sand bar developed.This observation reflects the deposition of the Chang 82 delta in the southwest of the Ordos Basin,which demonstrates that the experimental understanding has certain guiding significance for the study of the development style of delta front sand bodies due to the action of waves.

关 键 词：三角洲 波浪作用 沉积模拟 横向砂坝 沿岸流 

分 类 号：P512.2[天文地球—地质学]