Caves are cavities that form in hillsides, in cliff walls, and underground, and are accessible at Earth's surface. Typically, they form in soft, fractured, or soluble rock as a result of natural mechanical and chemical processes that continue over thousands of years. This interactive activity from NOVA offers animated explanations for how ocean waves, lava, slightly acidic groundwater, and, in a supporting role, microbes account for the variety of cave formations on Earth.
Visit the program page here.
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