利用放射性示踪沙定量观测长江口北槽航道抛泥区底沙运动  

QUANTATIVE DETERMINATION OF SEDIMENT MOVEMENT AT THE LANDWARD SPOIL GROUND IN THE YANGTZE ESTUARY WITH RADIOACTIVE TRACER

作　　者：李樟苏[1] 程和森[1] 曹更新[1] 吴永进[1] 杜效云[1] 王守家[1] 魏明成[1] 

机构地区：[1]南京水利科学研究院

出　　处：《海洋工程》1994年第2期59-67,共9页The Ocean Engineering

基　　金：我国与国际原子能机构的技术合作项目;国家自然科学基金

摘　　要：１９９１年６月在国际原子能机构的合作下，在长江口北槽航道上抛泥区进行了一次大规模的放射性示踪沙试验。示踪核素为钪－４６，总活度为１７．９５×１０^（１０）Ｂｑ（４．８５Ｃｉ），示踪沙投放总量为４９５ｇ。本试验目的是通过定量观测底沙运移的方向、路线、速度和输沙率，以期为北槽航道上抛泥区今后能否继续作为抛泥区使用提供直观可靠论据。本次试验观测资料表明，在北槽航道上抛泥区，在中小讯期间，无论是涨潮时投放的示踪沙还是落潮时投放的示踪沙都受落潮流控制，并向北槽航道中段输移。据测量资料分析，在上口抛泥区投放的示踪沙最终沿着１１０°的运动方向以７５８ｍ／ｄ的运动速度，在２６９~＃航标附近进入挖槽，单宽输沙率为４７．８ｍ~３／ｍｄ。This paper describes a radioactive tracer experiment carried out at the landward spoil ground of the North Passage in the Yangtze Estuary in June of 1991. The scandium-46 was selected as the tracer,the total activity released is 17. 95. 1010Bq (4. 85 Ci),the amount of the scandium-46 glass is 495 g. The purpose of the experiment is to determint the sediment movement direction, path, velocity and transport rate. Those provide the direct evidence for using the landward spoil ground in the future. The experiment result shows the sediment movement was governed by the ebb tide current during the period of middle and neap tides when the radioactive tracer was injected both on the flood and ebb tides, and the sediment moved from the injection points to the middle of the North Passage near the navigation buoy No. 269. The direction of the sediment movement is 110°,the particle velocity is 758 m/d, and the sediment transport rate per unit width is 47. 8m3/md.

关 键 词：放射性 示踪沙 定量 航道 底沙运动 

分 类 号：P75[天文地球—海洋科学]