海底峡谷浊流汇流后含沙量与速度变化研究  

Variations in sediment concentration and velocity after turbidity current confluence in submarine canyon

作　　者：张子涵 任宇鹏[1,2] 陶威 许国辉 靳梓堃[1,2] ZHANG Zihan;REN Yupeng;TAO Wei;XU Guohui;JIN Zikun(Key Laboratory of Marine Environment and Ecology,Ministry of Education,Ocean University of China,Qingdao 266100,China;Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering,Qingdao 266100,China)

机构地区：[1]中国海洋大学海洋环境与生态教育部重点实验室,青岛266100 [2]山东省海洋环境地质工程重点实验室,青岛266100

出　　处：《海洋地质与第四纪地质》2024年第4期78-87,共10页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金“海底峡谷弱稳定沉积物推动式剪切破坏传播及其对沉积地层的影响”(42206055);“风暴浪作用下海底高浓度含沙层形成过程的观测研究”(41976049)。

摘　　要：高速的浊流具有强大的破坏力,威胁着海底结构物的安全。海底峡谷是浊流向深海运动的重要通道,其中许多海底峡谷具有多条分支峡谷,而分支峡谷与主干峡谷浊流发生汇流后,含沙量、速度可能会增加,进而破坏力增强。本文通过室内水槽试验和数值模拟,研究了分支峡谷中的浊流汇流到主干峡谷中含沙量和速度的变化,并与仅有主干峡谷浊流的情景进行了对比。研究发现,发生汇流时,浊流的高度、含沙量和速度在头部均有增加,在汇流发生过后会有所减小,但含沙量和速度仍大于不发生汇流时的情况。本文试验结果可为有分支峡谷发生浊流汇流的现场监测位置及项目、速度推算提供指引。High-speed turbidity currents are very destructive and threaten the safety of seabed constructions.An important channel for turbidity currents to move to the deep sea is submarine canyons,of which many have multiple branches.Once a branch meets the canyon with turbidity currents,the sand content and the velocity of turbidity currents could be increased,and so the destructive power.We studied the changes in sand content and movement velocity of turbidity currents in branch canyons converging into the main canyon,to which the scenario of turbidity currents in main-canyon-only was compared.Result show that the height,sand content and velocity of turbidity currents were increased at the head when confluence occurred,and decreased after the confluence occurred.However,the sand content and the velocity were still larger than those without confluence.This study provided guidelines for site selection and velocity calculation for field monitoring when turbidity currents confluence occurs in branch canyons.

关 键 词：海底峡谷 浊流 汇流 速度 含沙量 

分 类 号：P736[天文地球—海洋地质]