Underground 'Snowy River' Alive Again

July 27, 2007 — The largest calcite cave formation in the world has astonished researchers by coming alive with water, according to volunteer cavers who have dug a new, safer entry passage into the New Mexican treasure.

Previous study of the calcite encrusting the two-mile-long "Snowy River" in Fort Stanton Cave just after its 2001 discovery had indicated that 150 years had passed since it had flowing water. So it was with great surprise on June 30th when volunteer cavers reached the cave by a new route and found a foot of flowing water.

"It will presumably dry up and precipitate another layer of calcite," said cave researcher Penelope Boston of New Mexico Tech in Socorro.

The wetting, drying process appears to have been going on with less and less frequency since the end of the much wetter Pleistocene epoch, she told Discovery News.

The discovery of flowing water underlines the great scientific importance of the spectacular cave formation, she said. Snowy River’s calcite is thought to contain a natural archive of Southwestern climate, including El Niño conditions, going back tens of thousands of years.

The calcite crystals are a lot like ice cores, but better, said Boston. For one thing, they stay put, whereas ice can flow. Calcite can also entomb and fossilize rare microbes as well as preserve a lot of chemical information about past climates and temperatures. She and her colleagues are hoping to carefully extract a core of the many layers of calcite from a plunge pools in the river, where the calcite appears to be thickest.

Researchers have been working to get similar information out of single stalactites, Boston said, but they are somewhat less reliable, since they can be affected by local conditions. "But a river is more homogenized," she said — especially a two-mile-long river that flowed and dried up at the same time, for eons.