2022 on the west coast of Thailand:
“The limestone towers around Krabi and Ao Nang have to be understood as ‘outdoor dripstone caves’. The stone is dissolved by rainwater. The plants that cover the upper part of the towers help with this. The calcareous water then runs down the outside of the tower. The water evaporates, the lime precipitates and builds up the spectacular dripstone balconies.”
“The process is as follows:
1) At the beginning, the towers are not yet overgrown. Rain washes out the stone. Below, the sea water erodes the stone.
2) The plant growth produces acid, which accelerates the decomposition of the rock. The dissolved limestone runs down with the water. In the lower part of the towers, dripstones are formed.
3) The dripstones grow into mighty columns that can even reach the ground or the sea.
Unanswered questions:
The water washes out many caves on the outside, but these disappear after a few metres into narrow crevices. The question is whether there are also cave systems inside and whether these are connected to the outside caves. At the rock of Arin's first dive, there was a continuous cave passage under water. This is an indication that both cave types are actually connected.”
