Terra School: Alpine Rivers

Jakethesnake8_8

Firemage
Pronouns
he/him
Welcome back! This time, we'll be looking at mountainous rivers

So this type of river differs from lowland rivers in a few ways. Due to their elevation, they typically cut through more stone than dirt. This typically results in much more gravelly, pebbly riverbanks. Furthermore, water is being forced downwards at a much steeper slope than lowland rivers, and over a smaller area. The result of this is much faster moving water, which consequently causes more erratic erosion. When these rivers get a bit more space, they have more space to form more channels. These are called 'braided rivers' as the various channels of interlocking streams and small bars create a braiding effect. Another consequence of faster-moving water is that larger sediments are carried with it. Mountainous streams start as what is called a 'catchment funnel', which is where all the water, gravel, dirt and rocks are picked up by the water. Catchment funnels occur high on mountainsides. Next, the river flows into a 'drainage channel' at high speeds. Finally, it becomes an 'alluvial fan', where all the debris is deposited. Typically, such fast-flowing rivers result in scouring, which refers to the erosion of the riverbank at a vertical angle. This is because sediment cannot be deposited here, as it just gets washed further downstream. Only once the river slows down will the banks be more gradual.

Here are some examples in-game of mountainous or hilly rivers


Typically, there are less muddy riverbanks and either bouldery or pebbly riverbanks.

To shape these rivers, I use //sel convex and //curve (see other river tutorial). Then I like to hand place layers so I get the desired effect. I also add boulders myself to make it look the way I want. This does take a bit of time, but it ends up being worth it, I think. Another option is using /b snow with voxel sniper. Holding gunpowder in your hand, type /b snow and right-click. This creates a gradient of snow layers which you can then replace with the desired pebble layers.