Explorers just uncovered Australia's deepest cave. A hydrogeologist explains how they form.

Stalagmites and stalactites From a research perspective, caves are incrediblyvaluable because they contain cave deposits (or"speleothems") such as stalagmites and stalactites. Explorers just uncovered Australia's deepest cave. So, as you can imagine, cave formation can become quitecomplex: the specific composition of the karst, theacidity of the water, the level of drainage and theoverall geological setting are all factors that determinewhat kind of cave will form. [Extracted from the article]