A lizard basks on top of a very uncomfortable looking dolomitised grainstone.
This dolomitised layer is part of a sequence of platform carbonates that formed 550 million years ago. Only some of the layers are dolomitised, and it is unclear whether the dolomite is primary, or formed secondarily, possibly as a result of Mg-rich fluids flowing along small faults.
(c) Geology for Global Development 2013
