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Gechi Qalasi geosite

There are several travertine springs in the Jolfa region. Travertine is a type of limestone formed resulting mineral springs (whether hot or cold) mostly in land setting.

Developing travertine springs requires volcanic activity and presence of underground limestone formations. Downward groundwater warms when contacting igneous rocks, increasing its carbon dioxide solubility and develop its acidic character. These hot waters can easily dissolve calcareous rocks in their way through subsurface strata. Then they reach out surface ground through fractures and joints, immediately release their carbon dioxide gas content caused by change in temperature and pressure conditions. The consequent is deposition of limestone on the spring bed, called travertine. Travertine is originally colorless, but because of the presence of impurities and some elements in different concentrations, bacterial activities as well as changes in the spring activity, they can be found in various colors with different layer textures. These sediments usually occur as horizontally thin bedded layers that are limited around the travertine spring openings, making small-scale or wide-spreading flat hills. This spring is an artesian spring that push out water and fine calcite particles with variety of colors including yellow, lemon, red, brown and white which along with the aragonite crystalline travertine makes an eyeful view.