The wind shifts. The stench of rotten eggs makes it nearly impossible to breathe and the hot fog clouds my view. I hold my breath and close my eyes, imagining the fog growing thicker, crushing me. Then without warning the wind clears and I’m enveloped once again in the cold, dry air. The heat feels like a lost dream. I shiver as I analyze my surroundings.
By Shannon Hall | Nautilus
Before me lies a steaming blue spring with concentric rings of green, yellow and dark red. I turn around to see another pool. But the rising fog is so dense, I can only guess at the existence of blue water below. Sometimes I glimpse bubbles boiling from some unknown source. The pools are a small sampling of the 10,000 geothermal features that dot Yellowstone’s caldera and hint at a mysterious hot spot beneath the crust.
It’s this alien landscape that makes it surprisingly easy to believe that northwestern Wyoming sits directly above a supervolcano — a behemoth far more powerful than your average volcano, with the capacity to eject more than 240 cubic miles of material.