I know this site is long overdue for a substantial post. Today, we’ll have to settle for a brief – and missed – “Friday Photo” submittal. I am both flattered that, despite the lack of new substance for over two months, there has been visitors to the site every day, and ashamed that I have not been able to keep up with my weekly/biweekly posts as I had previously promised to supply.
However, I have not been ignoring you for no reason. As I’ve mentioned before, I am currently attending graduate school and am in my final semester of coursework. In addition to the typical workload that comes along with the territory of any master’s student candidate, I am keeping myself active in multiple student and professional organizations as well as continuing to work for the engineering and environmental consulting company where I’ve been employed for over six years.
I’m not trying to make excuses – ok, maybe I am a little – but I want you to know that I fully intend on continuing to run this site for years to come, and that you can be confident that new, exciting, entertaining, educational, and maybe even enlightening(?) posts will begin to appear more often. But no promises on my efficiency anymore! At least not until I earn that Master’s degree!
Now, for the real post:
I recently spent a week in Denver, Colorado for the national Geological Society of America conference. The week-long event included hundreds of themed talks, field trips, exhibits from multiple businesses and schools…plenty to keep anyone busy for the week. While the conference itself was exciting in and of itself, some of my more memorable moments were from the one day trip I took – along with some colleagues to the Colorado Springs area. During this trip, we stopped at Florrisant Fossil Beds, ate lunch on the summit of Pikes Peak, and stood in awe among the towers of sandstone in the Garden of the Gods.
While these stops (and some of the others we made) were amazing in their own way, the latter was my favorite. Of course, by this time I had killed not just one, but two of my camera batteries, leaving me with only a 3.0 mega-pixel camera phone…which also died by the time we made our way to the best part (pictured above). Luckily, there were another ten people on the trip who took plenty of pictures, one of which is featured in this post. Thanks, Ode!
The park was privately owned by Charles Elliott Perkins until 1909 when, keeping to Perkins’ wishes, his children donated the land to the City of Colorado Springs with the stipulation that it remain a free and public park. The spectacular sandstone ridges of the park have their roots several hundred millions of years earlier, when the sandstone formations in the park were first deposited as alluvial sediments eroded from the Ancestral Rocky Mountains. These sediments were deposited in horizontal layers over the area, later being buried by finer desert sands around 245-270 million years ago. Eventually, a large portion of the region was submerged by an intermittent shallow inland sea, which covered much of central North America by the late Cretaceous Period, depositing even more sediment and adding to the horizontal layering of the present-day rocks. Many of the dinosaur fossils found in the region, including within the park, were from this time. The culmination of this sedimentation led to the formation of thousands of feet of sedimentary rocks. Keep in mind, they are all still oriented horizontally, as they were initially deposited.
About 65 million years ago, right around the end of the Cretaceous (when dinosaurs became extinct), the Laramide Orogeny began. This event describes a mountain-building process which, in this case, resulted in the formation of the second set of Rocky Mountains. During this process, a large granitic body was forced up through the ground, causing the overlying sedimentary rocks to bend, break, and erode. Heavy faulting also became prominent in the area. The Rampart Range fault network, running through the park, is a good example – and evidence! – of this process.
Believe it or not, we are actually on our third set of Rocky Mountains! The second set had about 30 million years to erode before this third set began to form between 35 and 7 million years ago. The Pikes Peak Batholith (a very large igneous body) was forced up through the overlying rock. Much the same as the earlier orogeny, the sedimentary layers were bent, broken, and eroded away. The layers of sedimentary rock were tilted completely (or very nearly) vertical when the Pikes Peak Batholith punched through them. Inter-bedded layers of shale eroded away over time while the more durable sandstone ridges, the tallest reaching over 320 feet high, have resisted erosion for millions of years. The result of this process was not only the current Rocky Mountains and Pikes Peak, but the geologic phenomena which helped to establish Garden of the Gods as a National Natural Landmark in 1972.
As with all geologic processes, the story of Garden of the Gods is far from over. Erosion due to water, wind, and the freeze-thaw effects in the late fall/early spring continually wear down even the most durable rocks in the park. While there is no reason to worry about it disappearing during our lifespan, I still recommend getting out there as soon as you get a chance…just because it is that cool to see in person. As I have always found, pictures cannot do nature justice.
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