That’s true of much of the world, isn’t it? I can’t speak for the rest of the world, but here in NC, surface water drives groundwater out. Counterintuitive I know, but having been involved with putting a well in at a lake house, I can say that it’s a definite challenge and the well was unusually deep.
Even the mountains that form the Vegas Valley (here) have aquatic fossils, on top of them!
I was just expanding on your original point.