A Virtual Field Trip to the Front Range of Colorado

        This is the second major stop of a virtual field trip to the Front Range and the eastern boundary of the Rocky Mountains in Colorado. If you missed the first stop of this trip, west of Denver,, you should probably look at it and come back to this afterwards.

        For our second stop, we're just west of Colorado Springs, working along US Highway 24 as it climbs through and beyond Manitou Springs. West of Denver, we saw upturned layers of sedimentary rock on the east (donwthrown) side of the fault. Here's what we see along US 24, standing on the south side and looking east:

 

outcrop view
 

        As near Denver, we see eastward-dipping sedimentary rocks on the east side of the fault. On the other hand, west of the fault we see this:

 

outcrop view
 

        The image above shows a roadcut of northing but granite like the close-up below:

 

rock view
 

        This bright red granite, the Pike's Peak Granite, is the only rock to be found on the west side of the fault here.

 

        The point here is simply that we're seeing the same pattern here that we saw west of Denver: granite (or granite and gneiss) uplifted on the west side of the fault, and layers of sedimentary rock dragged up on the east side. To return to the sketch we used there:

 

rock view
 

        There's also a separate field trip to see the contact between the granite and sandstones, as in the green circle on the sketch above. However, we'll leave that for another day. Instead, we'll say goodbye with this evening view east over the granite of the Front Range, across the Front Range Fault to the sandstones in the distance, and finally out to the Great Plains.

 

rock view
 


Back to The main page for Railsback's virtual field trips

Back to Railsback's main page

Back to the UGA Geology Home Page