一、前 言 影响港址选择的因素很多,在川江山区河流非冲积性河段上,一般要求港址选择在急流卡口上游的缓水段;或选在水深流缓、枯水又无淤积的沱内。四川山区河流中沱比较多,如龙王沱、唐家沱、白沙沱、猫儿沱和兰家沱等等,有些沱枯水无淤积,水深流缓,自然是筑港的良好所在,但有些沱有冲有淤,一个沱内就存在不同程度的淤积区 I. INTRODUCTION There are many factors that affect the choice of Hong Kong site. In the non-alluvial rivers of the rivers in mountainous areas of Chuanjiang River, it is generally required that the Hong Kong site select a slow-water section upstream of the snap-caps. Alternatively, Tuo. There are more rivers in the mountainous areas of Sichuan, such as Longwangtuo, Tangjiatuo, Baishantuo, Ma’erituo and Lanjiantuo etc. Some of them are silt-free and have slow flow and low water. Naturally, it is a good place to build a port. However, Chong silt, a Tuo there are varying degrees of siltation area