The great thing about taking an Earth Sciences class in New Mexico is that this state seems to have almost every kind of Earth Science! Oceans are the obvious exception to this, but fortunately Ms. Berryhill’s class at McCurdy High School is learning about volcanoes. We have plenty of those.
Last Thursday we took our McCurdy students to the Valles Caldera. This lovely location is pretty unique. In fact, it’s where geologists figured out how a caldera works. Unfortunately, due to very heavy rain the evening prior, we could not venture into the preserve.
We began at one of the Highway 4 pull offs, where we use plexiglass to outline the shape of the terrain across the Valle Grande. As you can see from the photo, low-hanging clouds presented a small obstacle, but the students did great.
After the students finished their artistic renderings, we held them back and examined them. What is this landform? Why is there such a large valley? What caused this?
Some students knew the answer- a caldera. The real trick was to put giant flash cards of caldera formation in the correct order. The students really enjoyed this and debated the order for at least 15 minutes. Eventually we got it right.
Our next activity was to model a caldera eruption with flour. This relatively simple activity really demonstrated the caldera collapse after the initial eruption.
We had one other model, which doesn’t fit Valles Caldera, but not all eruptions are the same. We created a volcano out of gelatin, and we used a 30 CC syringe to create dikes out of food coloring. This activity was also really neat- we were able to model a fissure eruption.
By the end of these demonstrations, students had a pretty good idea of how Valles Caldera formed. We were very fortunate to be joined by New Mexico geologist Matt Zimmerer. Not only is Matt very familiar with Valles Caldera, he was able to answer quite a few general geology questions.
After quite a while at the Highway 4 pull out, we continued down the road. We stopped briefly at Battleship Rock for lunch and another geologic explanation before heading to the Soda Dam. Most of us in New Mexico have driven past this roadside attraction many times, but it seems like few people actually stop to examine it. It’s definitely worth a stop!
The soda dam has formed as calcium carbonate has precipitated out of the water to form travertine.
The students really enjoyed exploring the soda dam, and climbing around on it seemed to wear them out. Almost everybody napped on the way back to Espanola.
All in all, it was a fantastic adventure. Despite a gloomy weather forecast, we had no rain until we were back in Los Alamos. It was another great day of science with our local students!