Well, OK, not since 950 years ago, unless you are out on the Malpais at one PM on a sunny August day, in which case you need to have your head examined as well as getting your hands treated for burns.
Over millions of years, the stresses and strains on the Colorado Plateau, Mogollon Rim, and Rio Grande Rift caused the land to tear, and sent bubbles of molten rock up to the surface. Some blobs cooled in place, becoming batholiths and laccoliths, sills and dikes. Others broke the surface and either oozed or blasted into the air, leaving volcanoes behind. Blast or flood depended on the chemistry of the lava and the presence of water.
The youngest volcanic rocks are the cinder cones near the San Francisco Peaks. Indians saw the eruption a mere 950 years ago. The bulk of the stones are older, but only by a million years or so. The core of the San Francisco Peaks is over a million years old, and seems to have come from two different lava blobs.
The oldest are the Hopi Butte volcanics, at about four million years old or so. Predating the Colorado Plateau’s uplift are the 25 million year old intrusions and necks of Agathla near Canyon de Chelley and the thirty-million year old core and dikes of Shiprock.
The Rio Grande Rift volcanics range from a fifteen-twenty million years to “a few hundred thousand.” Jemez Caldera’s last eruption was only a few tens of thousands of years ago, although that one was small. Not like the blasts one and a quarter million years back that left hundreds of feet of glowing hot volcanic ash all over the place, and eventually collapsed the mountain into the modern caldera. Which is dormant, with geothermal activity and little earthquakes, not extinct.
The mountain and its outpourings of lava and ash formed the Jemez Plateau, the shape looming in the background of the photo below. The shot was taken from Museum Hill in Santa Fe. The plateau also gives its name to the Jemez Lineament, the angled line of cones, fissures, and other things that crosses the Rio Grande Rift from southwest to northeast, and ends (at the moment) with the little neck of Two Buttes in Colorado.
Mt. Taylor in western New Mexico looms over the Rio Grande Rift valley and the lands farther west. It seems to float behind the Albuquerque Volcano Field west of the city*, and dominates the skyline on I-40 all the way past Gallup. Coming from the west, you see it rising at least sixty miles inside the Arizona border, especially if storms have caught on the peak. It is one of the four Navajo sacred mountains, along with the San Francisco Peaks. Broken lava covers the land south of the old volcano, forming “El Malpais,” the bad land. The a’a lava is rough, hot, eats cheap hiking boots, and was avoided by anyone sane. In other words, a geology student’s paradise, between September and early June. The malpais is only 3900 years or so old, and has grass clinging to it, but not much else. Indians probably saw it emerging, and fled.
Some day, I am going to spend at least a week just doing rock stuff around the Colorado Plateau in western NM, and then do a similar week in AZ. Preferably when it is is not 100 F.
Cat Rotator's Quarterly 
Back in the’70s, when I travelled through that area, the malpai fields that were accessible from the road had warning signs. Since I wore rubber-soled shoes, I heeded the warnings.
Rough country, fascinating geology
El Malpais in that photo looks a lot like parts of the Craters of the Moon formation.
Good observation! The two main types of lava flows share a lot of similarities. You get smooth and ropy and thick, or nasty, jagged, and often thick, depending on the chemistry of the magma and the amount of water. The photo could also be in Hawaii, or a few other places.
I need more coffee, but I’d need something stronger before I tried to walk on very very hot rocks. [Crazy Grin]
Louis L’Amour used the Malpais in a couple of his stories. It’s fun to see what it looks like. It’s odd to realize that I did see it forty-five years ago when I was a beginning geology student but hadn’t read L’Amour. I didn’t really click on what I was looking at. (To be fair I was hanging out with soft rock types who were not interested in the volcanics of the area At All.)
I’ve driven all over much of Colorado and New Mexico, and seen a lot of unusual terrain. If you’ve never seen the area, I recommend the Valley of Fires State Park near Carrizozo, New Mexico. It looks like the Malpais. Driving the highway from Raton to Clayton, NM, passes Capulan National Monument, one of the more perfectly preserved cinder cones in the area. The road from Raton to Angel Fire passes some fantastic basalt cliffs. The Spanish Peaks, north of Trinidad, CO, are twin volcanoes. If you take Route 12 to the west, you will drive through Stone wall, named for the volcanic dike to the west of town. As you continue north toward La Vita, you will pass the more than 500 dikes that radiate out from the Spanish Peaks.
I’ve seen all of those except the Valley of Fires. We didn’t have time to stop during that trip. Capulin is great fun UNLESS it is deer fly season. I set a new personal speed record on the trail because of the deer flies. Ow, ouch, ow!
Great info, thanks! And the Malpais has its own set of issues if there are lava tubes, as they can be collapsed just by walking on them (even if you don’t realize it is a tube).