I was digging in the abandoned ruins just outside the starting location. When I dig I typically dig in a circular fashion and slowly make my way down so I'm not trapped under a ceiling of rock by tunneling too deep. Yesterday, I hit the bottom of the map and then all of the rock disappeared completely leaving me with only the exposed relics, power stones, old parts, etc., visible. And yes, I was able to fly around and collect these. I've attached a picture below for your review: