Post 1: Continental Drift and the Glenwood Springs Vapor Caves

Continental Drift and the Glenwood Springs Vapor Caves

According to Continental Drift Theory, about 94 million years ago, during the late cretaceous period, the earth looked very different. Colorado was a beach on the Cretaceous Seaway, as shown in Figure1.



Figure 1: A projected Map of the earth 94 million years ago, according to the Theory of Continental Drift

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Roughly 75 million years ago, at the start of the Eocene epochs, the Laramide Orogeny began. During this Laramide Orogeny an oceanic plate and a continental plate collided. The collision caused the subduction of the oceanic plate to the continental plate, otherwise known as compressive thrust faulting. As illustrated in Figure 2.




Figure 2: A diagram of a Compressive Thrust Faulting, forming the Rocky Mountains.

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Consecutively a period of uplifting also began in the region, creating even more pressure. The only direction for the pressure to go was up. This caused the continental Crust to break resulting in 50,000ft tall mountains known as the “Ancient Rockies”. Scientists believe that, through a combination of weathering and continued uplifting, these “Ancient Rockies” reduced to the 14,000ft modern Rockies we see today.

As shown in Figure 1, North America was divided by the Cretaceous Seaway, as earth’s tectonic plates continued to shift the Cretaceous Seaway was closed by two land masses. Creating what is now known as North America. Some of the water from the cretaceous sea was absorbed into the continental crust. Evidence of the accuracy of this theory can be found in the Glenwood Springs Vapor Caves.




Figure 3: A picture of the Glenwood Springs Vapor Caves

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The Vapor Caves are made of Chemical Sedimentary rocks; this type of rock is formed by evaporation of water. The Vapor caves are limestone, indicating that the water solution that formed these caves contained a lot of salt. From this knowledge we can draw the conclusion that a large body of water, high in salt content, was once in contact with the Continental crust of this area. The theory of Continental Drift is the best explanation of how “ocean water” created caves in the Rocky Mountains.



The information found in this Blog Post was taken from Professor Allen's Introduction to Geography 1202 class lectures: Tectonics Processes, Earths Innards, and Diastrophism: Faulting.