I came across this pool in the rock just as a second rain storm approached. The heart-shaped depression was still full from last night’s 1.8 inches. I know because I check the rain gauge. I’m sure the image here is not human-made, yet it is near some prehistoric rock art. The white outline is carbonate deposits from evaporation of previous rainwater, and gravel is washed into it as it fills.
The approaching rainstorm sweeping like a silvery curtain across the landscape while you watch — that photo captures it the way I remember in the Chihuahuan Desert.