摘要
根据黄河口卫星遥感数据和河口滨海区水文、泥沙实测资料，对河口区洪水的平面扩散和含沙水层特征进行分析，结果表明：在洪水期，河口高高潮到低低潮线之间主河道两侧存在大范围漫流区，片状水流汇入网状汊沟入海，主河槽过流仍很明显，随着流量减小，漫流现象减弱乃至消失，推测口门区主河道的造床流量约１０００ｍ３／ｓ；ＴＭ１～３合成与ＴＭ６温度制图发现，在河口浅水区存在河海相互作用的混合带，混合带宽度与河流流量成正比，混合带中富集了大量悬浮泥沙，造成河口区快速沉积，黄河口滨海区切变锋常在此带中形成，实测锋带的总密度高于围域水体，表明切变锋具有二次发射异重流的能力。将实测获得的水体含沙量Ｃ、盐度Ｓ、流速Ｖ、水体剩余密度σｔ（与温度、盐度有关）、水体总剩余密度σ及水层厚度ｈ进行聚类分析，对黄河口滨海区不同河流来水来沙条件下的水层进行分类，并对各种水层特征及水层垂向组合特征进行了分析，即洪水期滨海区属不均匀流体，成层性明显，河口来水来沙对其分层起重要作用，共区分出６种典型水层，三种异重羽状流层（高、中、低）在大水期经常发生，频率达４２．５％。中水期区分出５种水层类型，明显反映出盐水的作用加强，河流作用表现在异轻羽状流层的存在；枯水期?
In this paper,a lot of data of Landsat images and measurements are analyzed for studying the surface dispersal and water layer characteristics off the Yellow River mouth during the flood season.The results show that river water flows over the major channel between high high and low low tidal line during the period of flood.The laminar flow water is converged in the net gullies.The major channel is also obvious.The overflow will disappear with the river discharge decreasing.It is predicted that the major channel discharge would be 1000m 3/s.A mixture zone is found off the river mouth based on the Landsat images(TM1,2,3 for suspended silt concentration and TM6 for water temperature).Its width is related to the river discharge and plenty of suspended silts are converged and deposited there.The shearing front is often formed in the mixture zone.The measurement data show that the total density along the front zone is higher than ambient water and some hyperpycnal plumes would be launched from the zone.The water layer characteristics and vertical combination types are studied based on the analysis statistics of silt concentration(C),salinity(S),current velocity(V)and total density(σ and σ t)etc.The results show that the water is unsymmetrical and layered due to the high silt discharge in flood season.The frequency of the hyperpycnal plume is high off the mouth during the period of the river flood (42 5%).Some low density mud layers are identified above the seabed during different periods of the river discarge.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
1999年第3期1-10,T001,共11页
Marine Geology & Quaternary Geology
基金
国家自然科学基金
关键词
黄河
入海泥沙
泥沙扩散
河海相互作用
suspended sediment dispersal
shear front
hyperpycnal plume
remote sensing
Yellow River mouth
