黄河三角洲的形成和演变

黄河每年有8×108～10×108t泥沙进入河口地区。由于黄河的受水盆地浅,区域上又位于构造强烈沉降区,进入河口地区的泥沙约有80%淤积在陆上及滨海地区,逐步形成了现代的黄河三角洲。通过RS与GIS综合对比和地质成因分析,可揭示整个三角洲在河流动力和海洋动力综合作用下的快速淤进、蚀退,河床抬高和尾闾改道等一系列演变,其中又以海岸带的演变最为明显。近几年,受黄河来水来沙量减少和人为加固堤坝等因素影响,河口地区造陆速度减缓,其他地区海岸带蚀退变慢,河床进一步抬高,整个三角洲基本处于淤蚀平衡状态。

Form and Evolution of Huanghe River Delta

t sand enters into Huanghe river mouth every year. Due to its shallow intaking basin, and its location in strong descending area, 80% sand which entered into river mouth will fill in land and coastal area, then present Huanghe river delta is formed. Through synthentic contrast and geological origin analysis by using RS and GIS method, rapid filling and retrogradation, bed accretion and terminal river diverting are exposed in this paper. In recent few years, effected by decreasing of water and sand amount and firming of dam, land-forming speed in river mouth area is slow, retrogradation became slowly, bed accrection is lifting, and the whole delta area is in a balance condition of filling and retrogradation.