this is a collapsed hoodoo (a rock formation caused by differential resistance to erosion, meaning that the top part of the hoodoo is harder than the bottom, so the bottom erodes faster). my husband and i call them mushroom rocks. this one is along Highway 89A, leading to the north rim of the Grand Canyon. to give you perspective, the larger boulder was about three times my height.
here's one that hasn't eroded yet.
i'm not sure how inspiring these are, but i might use them for another setting in my book. (still debating.)