中更新世晚期,古金沙江曾在金坪子河段发生堵江,使得金坪子河段成为金沙江发育的局部侵蚀基准点,并影响着三堆子-乌东德河段的河流下切速率。金坪子、凹嘎、龙街和鱼鲊的平均下切速率分别为196~217、145~172、257~305、82~97 cm/ka。凹嘎河段和鱼鲊河段在河谷地貌形态和阶地堆积物形成年代上都有很大差异,其原因为金沙江河谷中存在着多级构造裂点或岩性裂点,两河段性质存在差异,所以该河段不宜做传统的阶地位相分析。金沙江三堆子-乌东德河段的阶地沉积物的重矿物种类较多,以磁铁矿、赤褐铁矿、绿帘石、石榴石为主,并含有稳定矿物锆石、金红石和白钛石,以及十字石、兰晶石等典型的变质矿物。

After the research of sedimentology, geomorphology and chronology in the Sanduizi-Wudongde reach, we come to the conclusion that the geomorphic feature of the lower reaches of the Jinsha River was formed in the late middle Pleistocene. The ancient Jinsha River was jammed in Jingpingzi and it turned into a local base level of stream, which influences the incision rate along the Sanduizi-Wudongde reach of the Jinsha River. The average incision rate of Jinpingzi, Aoga, Longjie and Yuzha are 196-217 cm/ka, 145-172 cm/ka, 257-305 cm/ka, 82-97 cm/ka respectively. Because of the tectonic knickpoints and lithology knickpoints of the Jinsha River and the distinctions of the fluvial characters, there are some differences in the valley geomorphic feature and the TL datings of the terraces between Aoga reach and Yuzha reach,so the analysis of the terraces height relative to the Jinsha River do not make out. The Sanduizi-Wudongde reach of the Jinsha River contain many kinds of heavy minerals, such as magnetite, russet iron ore, epidote,garnet, and contain many steady minerals and degenerative heavy minerals, for example zircon,rutile, white-titanium, crossed-stone, cyanite, and so on.