Sedimentary processes in Zenisu deep-sea channel revealed by side-scan imagery  

作　　者：吴时国 郭军华 TOKUYAMA Hidekazu 

机构地区：[1]Institute of Oceanology, Chinese Academy of Sciences,Qingdao 266071, China [2]Institute of Oceanology, Chinese Academy of Sciences,Qingdao 266071, China Graduate School of the Chinese Academy of SciencesBeijing 100049, China [3]Ocean Research Institute, University of Tokyo, Tokyo 2370061, Japan

出　　处：《Chinese Journal of Oceanology and Limnology》2005年第4期368-375,共8页中国海洋湖沼学报（英文版）

基　　金：Financially supported by the NSFC (Grant No.40276022), KnowledgeInnovation Program of Chinese Academy of Sciences (KZCX3-SW-219)and JSPS international cooperation program, and the Ministry of Scienceand Technology Project (G200046704)

摘　　要：Side-scan sonar data collected by Cruises 99-09 Leg 2 and 00-06 Leg l of R/V Yokosuka were used to reveal the sedimentary processes in Zenisu deep-sea channel. The middle and lower segments of the channel are rich in turbidite and other debrite deposits. By high-resolution imaging, three sedimentary processes were distinguished with distinct acoustic features. 1. Slumps and slides occur with contrasting backscatter, rough surface textures, blockings, and acoustic shadows at headwalls. They are very extensive and often in lobate form downslope. 2. Debris flow has uniform, general medium backscatter, sometimes showing marbling/lineation in lobate form. 3. Turbidity current is characterized by low backscatter confined to the channel as acoustic signal is attenuated. Regional tectonics must be the dominating factor that controls deposition pattern in this area.Side-scan sonar data collected by Cruises 99-09 Leg 2 and 00-06 Leg 1 of R/V Yokosuka were used to reveal the sedimentary processes in Zenisu deep-sea channel. The middle and lower segments of the channel are rich in turbidite and other debrite deposits. By high-resolution imaging, three sedimentary processes were distinguished with distinct acoustic features. 1. Slumps and slides occur with contrasting backscatter, rough surface textures, blockings, and acoustic shadows at headwalls. They are very extensive and often in lobate form downslope. 2. Debris flow has uniform, general medium backscatter, sometimes showing marbling/lineation in lobate form. 3. Turbidity current is characterized by low backscatter confined to the channel as acoustic signal is attenuated. Regional tectonics must be the dominating factor that controls deposition pattern in this area.

关 键 词：side-scan sonar image sedimentary processes deep-sea channel Nankai Trough 

分 类 号：P736.21[天文地球—海洋地质]