What effects would large-scale hydraulic mining have on the landscape?

Premise/question

Hydraulic mining is the process of spraying high-pressure jets of water into the ground to dislodge sediment and rocks. The muddy water from this is directed into sluices where valuable materials are removed. This kind of mining has a host of negative environmental effects, like increased flooding and erosion.

It's clear already that to scale this up is a bad idea, but let's do it anyway! : D

Say we have a large water pump floating in space. It propels water at around 300 km/h through an opening 1 km wide. It is used to mine a large swatch of desert 100 km across.

What will the landscape look like after blasting it for an entire day with this massive waterjet? Preferably, the answer gives a rough overview of the appearance of the landscape and briefly summarizes the processes behind that appearance.

Notes and clarifications

Handwaving solves the problem of how the pump is built and supplied.

If someone could also include a small description of the atmospheric effects, that would be very helpful.

The water is all recollected via a tube system, and never travels outside a 50-kilometre radius.

There are extensive aquifers here, bored by stone-eating organisms 100m or so underneath the sand.

I ask this question just so that I can accurately describe the landscape when writing.

The effects on life are negligible. The govt could care less about a desert planet.

The waterjet contains a small amount of abrasive; i.e. one milligram of sand per 100 L of water.

The desert in question looks like this, with mesas and other similar structures:

posted almost 4 years ago

pg4919‭

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