A few weeks ago when we did a hike in the Manzano Mountains I got carried away taking pictures of rocks along the trail. The wavy, layered metamorphic rocks that are abundant in the Manzanos look to me like beautiful pieces of artwork. I couldn’t resist posting some of my photos here.
Yesterday we were hiking in another area that compels me to take pictures of rocks. We were in the Quebradas, this time not an area of metamorphic rocks, but, instead, mostly sedimentary rocks. But sedimentary rocks form in layers, also, and with the fractures, folds and faults that occur on the earth’s surface many sedimentary rocks end up with fascinating shapes and patterns.
In addition to folding and faulting that reshapes the sediments, sometimes there are certain chemical processes that change the colors of the rocks in interesting ways. I don’t know all of the details, but in the laboratory of the geology class I recently completed, I remember the instructor explaining the round white dots in some reddish sandstones as places where a chemical impurity in the sandstone as it was being oxidized (changing it to the reddish color) would prevent the oxidation, leaving a white space around the impurity. There were many rocks in the Quebradas that had that feature and I photographed several samples.
Quebradas is a Spanish word meaning “breaks,” a rugged or rocky area. The BLM owns most of the land along the Quebradas Back Country Byway, a 24-mile dirt road east of Socorro that parallels I-25. There are 10 numbered stops, places along the way to park and observe various geologic features. Official hiking trails are nonexistent–you just wander anywhere in the vast emptiness that happens to capture your interest.
We parked at Stop 4, which is in the upper reaches of the Arroyo del Tajo. A nice hike that we have done before is to walk about 2-1/2 miles down the arroyo, observing the rocks (in Lee’s case observing the wildflowers, which are few and far between this time of year) and then rounding a corner to find yourself in this amazing slot canyon.
Walking out the other side leads to a nice ledge to stop and have lunch, which is what we did, before turning around and retracing our steps back to the car. Altogether an enjoyable winter hike.