这是一种鸡和蛋的问题,因为从来没有一个真正的点没有河流,或没有山绕流。>我的问题是是否山先前存在的河还是那条河在某种程度上导致山“出现”。沿着密西西比河的大部分区域,你描述形成的砂,砾石,直到前两次冰期的冰川沉积。虽然是固体基岩这一切之前,完整的山丘和河流景观。河流流沿着阻力最小的路径在重力的影响下的景观。这意味着,在一般情况下,他们将采取的路线最浅的梯度从源到大海。>是引导的山所有冰川存款的河吗?冰川沉积物形成的山的确会影响河流de-glaciation后发生的进程。尽管流动的冰川将会塑造了山放在第一位。同时,这条河会侵蚀的材料流动,所以它经常(但非常缓慢)开辟新形成景观。 Fluvial landscapes tend to produce very *dendritic* landscapes – that is, comprising of a dense network of channels with many small tributaries – in comparison to landscapes formed by glaciers. In this sense, the river will be causing new hills to 'appear' as it carves out new valleys and tributaries into the glacial material. Some of the smaller hills in the area may well have been formed entirely post-glacially. **Summary:** A mixture of both really. River courses are influenced by existing topography, but they also have the power to carve out new features into the landscape. ***Afterthought:*** If you go back far enough in Earth history, before the formation of water at the surface, there would have been some sort of topography (hills). So you could argue that ultimately the hills came first. *Sources*: Bennett and Glasser (2009) *Glacial Geology*; Anderson and Anderson (2010) *Geomorphology*