From left to right, Carol-Anne, Danni and Dale. They are following along one of the trench’s that leads beneath the escarpment. The bedding plane (around shoulder height) stretches out to either side. In mid-winter the water flows from the tunnels beneath the island. By all appearances the joints that score a nearby plain all lead off underground, it is just a matter of following them to where they disappear. This particular joint was the most obvious but I can see many others that could possibly be entered with a bit of work.