Building the Hogan

One of the things we noticed as we were digging in the soil was the quantity of heavy, black, pock-marked stones in each shovel full.  They range in size from peas to boulders, some of them well over 50 kilograms.  We began collecting them for later use and stacked them in several piles around the building site.  The small to medium stones will make excellent filler for a rubble trench.

Neither of us are rock hounds, but to us the stones looked volcanic in nature.  Not knowing the geological history of the area we prematurely concluded we were too far from a volcano that could produce such massive results, and that the rocks were too close to the surface to be from any local volcano.  After all, when was the last time New Mexico had a volcanic eruption?

It turns out that geologically speaking, it wasn’t that long ago.  The Carizzozo Lava Flow, in the central part of New Mexico is “only” about 4,500 years old, making it one of the largest young basaltic flows in the world.  After researching a bit further I learned that our state could actually be dubbed “The Volcano State”.   Twenty percent of the U. S. National Parks and Monuments based on volcanic themes are in New Mexico. There are more here than Arizona, Idaho, Oregon, and Washington combined.

The Taos Plateau Volcanic Field, the area in which our land is located is actually much older than the “young” fields to the south.  The last time volcanoes were active in the region was about 2 million years ago.  Phew!  So we have nothing to worry about, right?  Maybe not.  Geologists believe that it’s only a matter of time before there’s another eruption somewhere in the state.  Thankfully geologists deal in geological time, so I’m not worried about it happening on the Taos Plateau in the next 50 years.

For about 2 million years, between 4 million and 2 million years ago, the Taos Plateau would have been a dangerous place to put a house.  Between the lava flows, the raining stones and the noxious gas clouds, it would have been quite uninhabitable for even the most determined writer, painter or sculptor.  The scars on the plateau are still visible from the satellite images which show deep grooves in the land and discoloration left behind by the basaltic flows.

That the stones are sitting on, or near the surface we attribute to the fact that there’s very little vegetation in the area to decompose, therefore very little new topsoil.  The strong winds that continuously remove surface dust also contribute to their exposure.  Last but not least, the annual spring snow melt brings running water down from the peaks just to the south of us.

It is that very peak to the south of us that may have ejected these stones.  The innocent little knob of a hill, now softened by trees and prairie greens was at one time one of the many active vents on the plateau.  As the hawk flies, it’s less than a mile from our land.  It’s likely that the stones we were digging from our land and piling up neatly for our foundation spewed forth from the peak in a powerful eruption nearly 4 million years ago.

It was good to know something of the geological history of our land, despite the fact that the knowledge was slightly less comforting.

This area has been mostly uninhabited for all of time, except for the few migratory Native American tribes that briefly crossed over here to more fertile locations to the west, east and north.  The fact that it’s never been settled means that we’re the first humans to handle these 2 million year old stones.  

Perhaps it means they knew something we don’t.