Havasu Canyon
Just so! Tell you something else that will make you scratch your head - a relief map of North America. Even more localized relief maps yield some curious patterns. Such as, I suspect for most people, great amounts of moving water would be the first impression that would come to mind as a cause. We've all seen what creeks and rivers can do to the landscape; apply that on a much larger scale and, well, the scientific community™ will just have to work a little harder at explaining it to the unwashed. Of course expansion(?) cracks are everywhere.
To understand how the American landcape came to be, read these books by John McPhee:
“Basin and Range,” what has happened — and will happen! — in the region from California’s Sierras to Utah’s Wasatch Mountains. Learn how this geology is very similar to New Jersey’s. There’s gonna’ be a whole lot of shakin’ goin’ on and a new inland sea’s a-comin!
“In Suspect Terrain,” the geology of New York City and a short history of the geology of the eastern U.S. according to plate tectonic theory and glacial geology. The opening of the Atlantic and the erosion of the Appalachians.
“Rising From the Plains,” the utterly amazing geologic history of Wyoming’s high country, Yellowstone and much else. The human story that accompanies the narrative is as riveting as the geologic events.
“Assembling California” — how much of the state where I live was formed by terranes, large island chains the size of Japan, smacking into the American Plate. More will arrive over future millenia.
He’s put all 4 books together in one volume (with some edits) called “Annals of the Former World.” The guy is a brilliant writer/researcher and the books read like action novels.
http://www.nmnaturalhistory.org/volcano/raton.html
The volcanic field covers nearly 7500 square miles of northeastern New Mexico and adjoining Colorado and Oklahoma. The distinctive characteristic of the Raton-Clayton field is its great size, young age, continental interior setting, and possible association with one of the few volcanic hot spots in the world. If you start traveling east, you would not encounter volcanic rocks this young again until the mid-Atlantic ridge. The lava compositions are also somewhat unusual. And it is the site of Capulin Volcano, the eastern-most young and easily accessible volcano in North America...
Havasu Canyon
...I now propose that Earth expansion progresses, not from spreading at mid-oceanic ridges as usually assumed, but primarily by the formation of expansion cracks (often near continental margins) and the in-filling of those cracks with basalt (produced from volume expansion in the mantle)...