So this weekend we are driving from Portales to Las Cruces, a ridiculously long drive if you have ever had the misfortune of making the trip. It honestly feels as if you have made a rough circle around the entire state because the roads out here kind of suck. Despite the soul crushing boredom of the drive (at least this time I won’t be doing it alone) it does cross nearly all the most interesting geology in Southeastern New Mexico. We will leave the ancient Portales River Valley and cross the current Pecos River Valley, then go over the ancient volcano that is Sierra Blanca (we will miss the best views of the Lincoln folds though), once we leave the weathered mountain we will head towards Alamogordo and White Sands, finally we will drive across the Rio Grande Rift as we pass the Rio Grande River and drive into Las Cruces. Thinking about these structures is the only way I can survive the 5+ hour drives across this state.
I have already planned weekend excursions to all of the previous mentioned locales, and I have kind of worked out what I want to talk about in each of them, and since I’m going to Las Cruces to meet up with family I will only have Sunday to explore the southernmost portion of the Rift Valley—the Organ Mountains. I’m pretty excited about this upcoming weekend, and I can’t wait to check out what features there are. However, there is one feature of the Rift Valley that I want to talk about here, and that is the very river.
What makes the Rio Grande so much more special? Well the rio and its adjacent valley didn’t form normally with the stream starting high in the mountains and cutting its valley; instead the valley was formed by tectonic forces as a rift valley and the Rio Grande was originally a series of lakes in the valley which were eventually connected to form the great (at least by the standards of us in the Southwest where a sufficiently deep puddle might be labeled a lake and celebrated as a wonder of the natural world) river. After it leaves the rift valley, around El Paso, the river becomes a meandering stream which then of course is used to mark the border between Texas and Mexico, no problem there right? I mean nothing is more stable than a meandering river.
I love the amazing geology in New Mexico; it gives you numerous opportunities to see various different earth processes in action from dune formation to volcanics to stream action to cave formation and various other actions. The great thing is that you can plan out a camping trip to see most things you learn in the classroom. It is truly fascinating to get a real world demonstration of classroom ideas. Many of the classes in the geology department take field trips out into our surroundings, but there are only so many hours in a day so our time is limited. I like to supplement theses field trips by taking what I have learned and then to take a weekend to explore the area in greater detail. I highly recommend this to all geology undergrads. Take your free weekends and camp out in the world and see what you are learning about, it is awesome and a great learning experience.