My Favorite Volcanoes: Vulcan's Throne

I imagine everyone in the United States has a mental picture of what the Grand Canyon looks like, even if they've never seen it in person. Geologically speaking, it is spectacular and amazing--a slice into Earth's sedimentary history, hundreds of millions of years exposed to view. At the most-visited point (Yavapai Point, or Grand Canyon Village), the canyon floor is 5000 feet deep--almost a vertical mile down.

My favorite point in the Grand Canyon is far off the beaten path. (So far off, in fact, that you have to drive on dirt roads for at least 60 miles just to reach it.) It is Toroweap, a place where, roughly 1100 years ago, a cinder cone volcano erupted right on the canyon rim, sending rivers of basaltic lava cascading down the sides of the canyon.

In the middle right of the picture above, you can see the cinder cone (commonly called Vulcan's Throne) as well as the cascades of lava coating the canyon walls. The lava falls reached the canyon floor and actually dammed up the Colorado River for a time. Naturally, the river broke through after a relatively short time (exactly how long depends on who you ask; however, long enough to create some lake bed sediments upstream of the lava dams).

One of the most difficult rapids in the Grand Canyon is found here: Lava Falls. Much to my disappointment, despite the name, the rapids are not the result of remnants of the lava dams; they are caused by debris washed down from a nearby side canyon.

Lava falls cascading down the side of a 4000 foot high canyon wall? What more could you want? The Toroweap area offers more to the geologist and nature-lover, though. Around nearby Mount Turnbull, mantle nodules of lherzolite can be found. (I had just finished my first igneous petrology class when I visited Toroweap--finding these gorgeous fist-sized peridotites was like being in a candy store. Albeit a candy store of rusty red-colored rocks that you have to whack open with a sledge hammer to see the gorgeous green and black minerals inside.) (Yes, I'm strange, thanks for asking.)

One of the best parts about the Vulcan's Throne/Toroweap area is its isolation. Because of the difficulty in getting there, it is never crowded. While it is often very crowded (traffic jams! noisy crowds!) and occasionally hard to enjoy the main Grand Canyon area, Toroweap is very quiet. When I was there, I spent more than an hour laying flat on my stomach, nose over the edge of the canyon, staring down at the river thousands of feet below. I could hear nothing but the wind and the screech of a hawk or eagle, coasting below me in the canyon. Absolutely peaceful.