Beneath the Surface

Chapada Diamantina consists of an abundance of beautiful caverns and caves beneath the surface. These caves contain a vast array of rock formations and just enough surface light enters to create astonishing, majestic views. One of the most famous caves in Chapada Diamantina is known as Poço Azul or “the blue pool.”

Poço Azul lies close to the Paraguaçu River on the eastern side of Chapada Diamantina. It is known as a “karst” cave in which is created when limestone networks along with underground water, ultimately dissolving the limestone. When a certain amount of limestone is eroded from underground water a sinkhole can develop. This is exactly what has occurred in the case of Poço Azul in Chapada Diamantina as it lies at the bottom of one of these sinkholes.

  

This example is a direct correlation to the subject of Earth’s rocks, specifically sedimentary rocks. Poço Azul’s walls are shaped by sedimentary rocks, which tell its history over the past billion years. These sedimentary patterns depict Poço Azul’s history from lands of volcanic activity to seaside plains to low seas to glacial activity to much warmer seas, all of which occurred before five-hundred million years ago when penetrating tectonic activity took over the area.

Within karst caves such as Chapada Diamantina’s gem, Poço Azul, speleothems are created. These caves are known for this process since calcium carbonate solutions slowly drips down via “dripstones,” creating stalactites. The process continues and overtime the calcium carbonate solution drips down to the floor of the cave, resulting in stalagmites. The karst topography of Poço Azul is a prime example of how some of its amazing features come into place to create awe-inspiring scenery.

Overall, the combination of sedimentary rocks crafted through history with the chemical reactions of calcium carbonate solutions creating stalagmites and stalactites have made the karst cave of Poço Azul in Chapada Diamantina a modern spectacle.

Resources

http://www.atlasofwonders.com/2011/11/chapada-diamantina.html

http://gobrazil.about.com/od/Chapada-Diamantina/ss/Poccedilo-Azul.htm

http://geography.about.com/od/physicalgeography/a/karst.htm

http://geology.about.com/cs/basics_roxmin/a/aa011804b.htm