Patrolling Lake Superior’s Cthonic bedrock formations and Devonian boulders. Basaltic rock is dried lava sheets that decay into shelves littered with boulders at the edges. That is what we see here. Max depth 20 feet give or take a couple. Water has been cloudy this year due to rain, but finally cleared up enough here at the end of the summer to get this footage at one of my fave freediving spots.