Old Faithful's Underground Cavern Discovered
Posted: Apr 18, 2013 7:55 am
A big chamber sits about 50 feet (15 meters) underground, located southwest of Old Faithful, researchers report in a study published online March 30 in the journal Geophysical Research Letters. The exact size can't be determined, but they estimate the egg-shaped void is at least 50 feet (15 m) tall and 60 feet (18 m) wide. The cavern connects to a pipe angled about 24 degrees that feeds Old Faithful's maw.
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