Terraces
This beautiful photo was taken at the travertine terraces at Pamukkale, Turkey. This portion of western Turkey is undergoing extension, creating a series of normal faults and dropping down the land in a structure called a Graben. Pulling apart a piece of a continent causes warmer mantle rocks to rise upwards, increasing the heat flowing out through the planet’s surface and making shallowrocks warmer than normal.
Water also can travel along these faults. Water in this area seeps to a depth of several hundred meters along one of the faults where it is heated to temperatures of 60 or 70°C. At these temperatures, the water dissolves a tiny bit of the limestones buried at that depth. When the water reemerges at the surface, it cools off and releases CO2 picked up by dissolving the limestones. This temperature and chemistry change triggers precipitation of the dissolved minerals – this time as the limestone mineral travertine. These travertine terraces are young, but others in this area have been measured to date back over 200,000 years.
-JBB
Image credit: www.bestreviewsbase.com
https://flic.kr/p/Xyw339
Reference:
http://bit.ly/2xt6gsw
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