Pamukkale information, Pamukkale, Hierapolis Turkey
Pamukkale Formation

Pamukkale travertine is a type of limestone deposited at the mouth of the spring. Thermal sources on an important fault line of western Anatolia in Pamukkale are warmed up by subterranean heat and come out at 33-36 C. The water contains calcium hydro carbonate. Tectonic movements triggered frequent earthquakes in this area and gave rise to the emergence of a number of very hot springs. The water from these springs created Pamukkale with its large mineral content. When the hot water is in touch with the carbon dioxide, it starts to lose its warmth and also the carbon dioxide and carbon monoxide are released in to the air. As a result the calcium carbonate is precipitated. So the water forms magnificent viewed travertine. 

There is a high amount of calcium and carbon dioxide in the combination of the water. The chemical reaction from the start to the end is:

Ca (HCO3)2 >> CaCO3 + CO2 + H2O

Water channels carry water which comes out of the ground arrives to the terraces. But before water channels were built, water used to reach travertine by natural channels formed by running warm water. Because of the calcium in water, objects such as branch of a tree or a stone piece left in the flowing water are whitened in a short time.

According to the theocratic researches, flowing water can whiten approximately 4.9 km2 with 1 mm deposit. Running of the water in the same area for 14000 years, causes moss in travertine and spoil the whiteness.