Last updated: May 2, 2024
Place
Rocky Falls
Grill, Information Kiosk/Bulletin Board, Parking - Auto, Picnic Table, Restroom - Accessible, Toilet - Vault/Composting, Trailhead, Trailhead/Hiker Register, Trash/Litter Receptacles, Wheelchair Accessible
A natural cascading waterfall is a rare sight in Missouri. Few places in the Ozarks provide a glimpse of earth’s turbulent past as well as Rocky Falls. The reddish-brown rock you see here is rhyolite porphyry. It formed as molten rock deep within the earth and flowed onto the surface about 1.5 billion years ago. At the time, no living thing existed to see the awesome flow of glowing hot lava slowly advancing over the barren landscape.
Normally, a stream eroding softer dolomite, a type of limestone, would make a wider valley for itself. Since the rhyolite is harder, the stream tends to stay within whatever cracks that it finds, deepening them only a little by erosion. Thus a“shut in” is formed where the harder rock has “shut in” the stream. Farther downstream, past the constricting rhyolite, the stream valley widens once again. This allows the stream to expand into a pool.