During a drought period in the Pliocene (ca. 6 million years ago), the softer grasses in North America were largely replaced by harsher grasses, which had three times as much silica content.

Alaska has more than thirty known hot springs discharging water with temperatures in excess of 40 C (104 F).

Even the ocean has freshwater springs, and at these springs, freshwater can be taken right off the surface of the sea. Absolutely pure water is not actually clear and transparent in colour. It is actually blue!