It’s #FunFactFriday so I thought I’d write about the geology seen in Big Bend National Park (Texas). The Chisos Mountains (part of which you see in the image above) are volcanic in origin. One of those volcanic things you’ll see while driving the road through the park are intrusive dikes. Igneous means the rock is volcanic in origin. Dikes are igneous, and they are called “intrusive” because the magma intrudes upon and into the existing rock layers above it. You can see a long stretch of dikes exposed and sticking up out of the ground in this shot. The rocks around the dikes eroded away, leaving those flat-looking walls of rock, sort of like a zig-zaggy-edged rock fence running over the hillsides and up into the mountain flanks.
I’m looking through past Big Bend (as well as other parks) images to see if there are shots I have not edited, or – at the time – didn’t do as good a job of editing. I honestly can’t remember if I ever posted this image or not, back in 2013 (can it be 7 years ago??) captured during my December visit to this national park in southwest Texas. It was my first (out of four) trips there.
Copyright Rebecca L. Latson, all rights reserved.