If they wrote about “paleobasins” or “paleolakes” I’d have fewer concerns. The articles states that these things were carved into rock. We definitely know tha

If they wrote about “paleobasins” or “paleolakes” I’d have fewer concerns. The articles states that these things were carved into rock. We definitely know that water doesn’t carve rock into valleys unless that water is moving quickly. We also know that rock is generally less permeable than clay soil. Millions of people with clay soil use French drains, and these things sound like naturally-made French drains, but without the pipe. French drains work without the pipe (just not as well). People use them to move water to some other location, not to hold it in place so it can percolate down into lower levels of the ground! Getting water under the surface is not automatically useful! It has to percolate into aquifers. Maybe the next step is to build underground dams and then drill holes into the rock under the “paleo valley”.