And in between there's everything you could possibly imagine. I've never been any place where geology is more evident—or prettier."
So you like it? I say.
Oh, no, I love it, he answers with profound sincerity. "I mean I really love it here. The winters are tough and the pay's not too hot, but when it's good, it's just—"
He interrupted himself to point out a distant gap in a range of mountains to the west, which had just come into view over a rise. The mountains, he told me, were known as the Gallatins. "That gap is sixty or maybe seventy miles across. For a long time nobody could understand why that gap was there, and then Bob Christiansen realized that it had to be because the mountains were just blown away. When you've got sixty miles of mountains just obliterated, you know you're dealing with something pretty potent. It took Christiansen six years to figure it all out."
I asked him what caused Yellowstone to blow when it did.
Don't know. Nobody knows. Volcanoes are strange things. We really don't understand them at all. Vesuvius, in Italy, was active for three hundred years until an eruption in 1944 and then it just stopped. It's been silent ever since. Some volcanologists think that it is recharging in a big way, which is a little worrying because two million people live on or around it. But nobody knows.
And how much warning would you get if Yellowstone was going to go?
He shrugged. "Nobody was around the last time it blew, so nobody knows what the warning signs are.