Certain rock types are soluble in water, especially acidic water. Subterranean drainage slowly dissolves through a carbonate rock type called dolomite. The resulting gaps and cracks under the ground create slumps and hollows on the surface which are called sinkholes like the one at this Earthcache GZ.
Where drainage is unimpeded the sinkholes will continue to grow wider and deeper, emphasising the dynamic nature of this land. In this area of the Tarkine there are hundreds of sinkholes, caves and underground drainage systems. Although most sinkholes are dry, some are filled with water.
1. As rain falls it absorbs carbon dioxide. Does this make the rain it slightly acidic or slightly alkaline?
2. What is the name of the landform that results in this region when rocks dissolve in water?
3. Is this sinkhole filled with water? Why or why not?
4. There is a sinkhole nearby filled with water. What is the name of it?
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