‘The Rockies.’
Credit to: ME!
Taken on an iPhone (with a selfie stick!) Yep, I’m that tourist! 😅😆
Ah, the beautiful Rocky Mountains. If the rocks could speak, they would tell us about their puzzling origin. But for now, I will speak for them.
‘The Rockies.’
Credit to: My mom, Katharine Ramirez
Shot from iPhone
The Rockies shaped an exalted mountain barricade that extends from Canada through central New Mexico. While daunting, a view into the topography of the Rockies exposes disjointed sequences of mountain ranges with discrete geological roots. The Rocky Mountains margin is continental crust against the oceanic crust. The mountains formed during a period of concentrated plate tectonic activity that shaped much of the jagged landscape of the western United States.
The Jurassic to Cenozoic Periods were the mountain-building chapters that restructured the west from about 170 to 40 million years ago, (Frank, 2019). The last forming event, the Laramide orogeny, (about 70-40 million years ago) the last of the three episodes, is responsible for raising the Rocky Mountains, (Frank, 2019). America was agonized by the outcomes of recurring collisions as the chunks of the ocean crust descended beneath the continental edge. Slices of continental crust were passed along by subducting ocean plates, swept into the subduction zone, and frayed onto North America's edge, (Frank, 2019). The resulting tension pulled part of the oceanic plate higher in that area while yanking the continental plate downward, forming the Wyoming-Colorado Basin, (Minard, 2017).
This sketch shows the plate tectonic setting during the growth of the Rocky Mountains (Laramide orogeny). The angle of the subducting plate is expressively flatter, affecting the focus of melting and mountain building much farther inland than is normally expected.
Credit to: Frank, D. (n.d.). Geologic Provinces of the United States: Rocky Mountains. Retrieved from https://geomaps.wr.usgs.gov/parks/province/rockymtn.html
About 100 million years of plate collisions were intensive on the border of the North American plate frontier, far west from the Rocky Mountain area. The evolution of the Rocky Mountains has been a mystery to geologists. Generally, mountain structure is fixated between 200 to 400 miles inland from a subduction zone edge, yet the Rockies are hundreds of miles farther inland, (Frank, 2019). Throughout the process of the Rocky Mountains, the position of the subducting plate was suggestively compressed, affecting the emphasis of the mountain structure that was much farther inland than typically expected. Compression in this region created faults deep underground that allowed rock layers to thrust upward, forming the Rocky Mountains. The concept that a portion of the oceanic plate got pulled up by suction helps explain why the Colorado Plateau south of the Rockies appears moderately uninterrupted, even though it was also riding over the subducting plate. These mysterious rocks sure know how to move!
The kinds of rocks that were involved in this formation were the Precambrian metamorphic rock that forms the core of the North American continent and the Precambrian sedimentary argillite, (Paleontological, 2019). The faults that were in use during this formation were thrust faults or known as reverse thrusts. These faults are generally found in collisions zones, where tectonic plates push up mountain ranges such as the Himalayas and the Rocky Mountains, (GEOExPro, 2015).
To conclude my journal entry, I would just like to say that I love being surrounded by the Rocky Mountains. When I first visited Regis University, my mom shot this picture of the mountains peeking through the campus. I knew Colorado would be my new home.
‘Regis University view’.
Credit to: My mom, Katharine Ramirez
Shot from iPhone
‘The Rockies.’
Credit to: My mom, Katharine Ramirez
Shot from iPhone
‘View from the plane,’
Credit to: My mom, Katharine Ramirez
Shot from iPhone
Thank you for reading! 😊
References:
Frank, D. (n.d.). Geologic Provinces of the United States: Rocky Mountains. Retrieved from https://geomaps.wr.usgs.gov/parks/province/rockymtn.html
Hargreaves, A., Hargreaves, A., Whaley, J., & Whaley, J. (2015, April 27). The Magnificent Southern Canadian Rockies. Retrieved from https://www.geoexpro.com/articles/2015/04/the-magnificent-southern-canadian-rockies
User, S. (n.d.). Retrieved from http://geology.teacherfriendlyguide.org/index.php/75-southwestern/rocks-sw/588-rocks-region3-sw
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