Water Weathered Wonders

Being an island, it goes without saying the Phuket is subject to various forms of chemical and physical weathering. If one were to travel by boat or kayak just to the south east of Phuket, you would arrive at Koh Panak a large island with mountainous caves and various rock formations, peaks and cliffs. Within one such cave is a limestone organ that can only be reached by swimming in at low tide.


Koh Panak, Phang Nga Bay, Thailand.
This limestone is no longer growing since its water source is depleted.

Phuket and the surrounding islands are predominantly limestone which allows the water surround them to constantly change their shape. In some instances the tunnels that are scattered throughout this area collapse onto themselves creating a dry hong, exposing them to the sun.

Throughout Phuket you can find hongs, naturally made caves and grottoes.
Dry hongs are made by when cave roof collapse onto themselves. 

Stalactites are common along the exposed sides of the island.

The mountains that form Phuket, in this case Koh Panak, are sedimentary rock, often times covered in moss and limestone build up. Because of the general softness of this rock, the rising and falling of water levels causes the dissolution of the limestone and beautiful caves are made. The change in water levels is due to Thailand's two dominant seasons. Monsoons season brings heavy rain from the Indian Ocean from May to October, and from November to April it is much drier. The extended rainy season deposits salt water along the entire region leading to the altering of the mountain scales.

 

http://thebeachfrontclub.com/guide/koh-panak-phang-nga-bay-thailand-island-of-caves-hongs-tunnels

http://www.climateandweather.com/weather-in-Thailand