KirstenHeidel_FieldTripProject

Colorado’s Abundance of Geological Wonders

Adventure

A field trip filled with fun real-life observations of Colorado’s geological

wonders

By Kirsten Heidel

Trip Details

Our trip will begin near the south entrance of Chatfield State Park. We will be traveling northwest passing through Morrison and taking Highway 36 into the Rocky Mountains.

Along the way we will be making several pit stops to observe interesting geological points.

Be sure to bring snacks, drinks, and good music. This trip will take a few hours. If you’re 21 or older, there will be an opportunity to go gambling at Blackhawk. So bringing some extra cash is a good idea too.

Let’s get started!

Ready, Set… Go!Our trip will begin in the parking lot located near the south entrance of Chatfield. It is at the intersection of N. Roxborough Park Road and the highline canal.

Drive south 1.6 miles and turn right onto Titan road.

Titan road will turn into Rampart Range Rd. at a large curve. Follow Titan/Rampart Range for 2.5 miles until you reach Waterton road. Turn right.

Parking Lot at the South Entrance of Chatfield State Park

(Photo by Google Maps)

Ready, Set… Go!Following Waterton road for 1.6 miles, you will drive through Waterton canyon and pass over the south Platte river.

Fishing, biking, and hiking are abundant in the canyon.

View of the South Platte River in Waterton Canyon (Photo by Google Maps) View of the South Platte River in Chatfield State

Park (Photo by Kirsten Heidel)

The South Platte RiverThe South Platte River features high and slow velocities due to the constant change of shape and roughness of the channel.The river also features several sand and gravel bars in the middle of the river and on its banks. Some of these sand and gravel bars are point bars.The South Platte River feeds the South Platte River Basin pictured to the right. The South Platte River Basin is prone to flooding. In order to decrease flooding, dams, spillways, and canals (such as Chatfield Dam and the Highline Canal) were built.

Map of the South Platte River Basin (U.S. Geological Survey)

Destination Reached

Merge right onto S. Wadsworth Blvd. Drive 4.4 miles until you reach CO-470. Take CO-470 west (turn left).Drive 9.4 miles until you reach the Morrison exit. Take the exit and turn left onto Morrison road.After 0.4 miles, the road forks. Take the right fork, which is Mt. Vernon Ave.Our destination, Dakota Hogback, is on the right! There are parallel parking spots on both sides of the street. Hopefully it won’t be a busy day so parallel parking will be easy.

Dakota Hogback in Morrison (Photo by Google Maps) View from the Bottom of Dakota Hogback (Photo by Kirsten Heidel)

Climb That Hogback HighThis is the most physically demanding and exciting part of the trip! All paths lead to the top of the hogback so pick the path that is most appealing to you.

On your way up, be sure to look for old snail shells and observe some of the sedimentary rocks beside the paths.

Sedimentary rock and fossil snail shells found on Dakota Hogback (Photos by Kirsten Heidel)

Shells and Sedimentary RocksDuring the Paleozoic period Colorado was covered by a sea (“Colorado, US”). This explains why there are snail shell fossils throughout the state.

The sedimentary rocks found on Dakota Hogback are conglomerate. This is obvious by the rounded cobbles and pebbles.

The conglomerate rocks also formed in the sea. Ocean waves rounded the cobbles and pebbles (Plummer, Carlson, and Hammersley 143). Later, the soil settled and solidified around the cobbles and pebbles, forming the conglomerate rock.

Conglomerate rock and fossil snail shell found on Dakota Hogback (Photos by Kirsten Heidel)

Climb That Hogback HighOnce you reach the top of the mountain you can observe the rocks and determine what they are. The top layer of rocks are dakota sandstone (National Park Service).

In the photo to the right, we can see how plants contribute to the mechanical weathering of the sandstone. As the roots grow into the cracks of the rocks, the cracks expand.

Layer of Dakota Sandstone (Photo by Kirsten Heidel)

Pine tree roots growing into the sandstone (Photo by Kirsten Heidel)

Reaching the Top

Striations are one of the most notable feature of the dakota sandstone atop the mountain.

Striations in some fallen dakota sandstone (Photos by Kirsten Heidel)

Reaching the TopAnother notable feature is the cleavage of the sandstone. The pictures to the right show two directions of cleavage.

The picture below shows one direction of cleavage.

One direction of cleavage (Photos by Kirsten Heidel) Two directions of cleavage

Reaching the TopRock falls contribute largely to mass wasting on the hogback.

Past rock fall (Photo by Kirsten Heidel)

Reaching the TopIf you find a safe place to rock climb… do it! But make sure you have a friend with you just in case something goes awry.

The views of Morrison and Bandimere Speedway are spectacular. Photos here would make great Facebook profile pictures! Photos by Kirsten Heidel

Onward We Carry…After carefully climbing back down the hogback, we’re hopping back into the car and continuing to follow Mt. Vernon Ave. This will eventually turn into Hogback Rd.

Follow Mt. Vernon Ave./Hogback Rd. For 3.2 miles.

Turn right into the Stegosaurus lot.

Stegosaurus Parking Lot (Photo by Google Maps)

Hogbacks Are Like OnionsTake the trailhead at the north end of the parking lot. Follow this trail around the hogback until you are parallel with the highway and can see the layers of sediment. This area is also the Dakota Hogback.

Layers of shale and limestone (Photo by Kirsten Heidel)

Hogbacks Are Like Onions

Layers of shale, limestone, and dakota sandstone (Photos by Kirsten Heidel)

The Dakota HogbackDakota Hogback is an amazing sight to see right along the highway. The vividly colored layers of sediment give us just a small view of the of layers of sediment which lay beneath our feet.

The top layer is dakota sandstone, followed by limestone, and finally a couple of types of shale (National Park Service).

The hogback was formed as colliding plates lifted and pushed up the land.

Close-up view of one of the layers of shale (Photo by Kirsten Heidel)

The Dakota HogbackWe can see that rockslides and rockfalls occur on this side of the hogback too.

Evidence of rockfalls and rockslides (Photos by Kirsten Heidel)

Onward We Carry…Once we are done observing the spectacular colors of the layered hogback, it is time to get back in the car.

Turn right out of the parking lot and continue on Hogback Road. It will eventually turn into Highway 40 east. After leaving the parking lot, follow the road for 1.4 miles and turn left onto Heritage Road.

Follow Heritage Road for 0.9 miles and turn left onto 6 th Avenue. 6th Avenue eventually turns into Highway 93 north.

After following Heritage Road/Highway 93 north for 3.7 miles, turn left onto Golden Gate Canyon Road.

Take Notice of…Sometimes human impact in geology can be beneficial, especially when it comes to harmful mass wasting. Along several parts of Golden Gate Canyon Road, bolts in the rocks can be seen. These bolts prevent rockfalls.

Rock bolts (Photos by Kirsten Heidel)

Onward We Carry…Follow Golden Gate Canyon Road for 7.9 miles to Robinson Hill Road. Turn left.

Notice how the rocks along Robinson Hill Road display the same type of cleavage as the dakota sandstone on the Dakota Hogback.

Photo by Google Maps

Destination ReachedFollow Robinson Hill Road for 5.9 miles until you see a shiny outcrop of rocks on the right side of the road. The outcrop of rocks, which is mica schist, is your geological pit stop.

Outcropping of mica schist along Robinson Hill Road (Photos by Kirsten Heidel)

Mica Schist with Quartz

A large chunk of quartz found in the mica schist.

Close-ups of mica schist (Photos by Kirsten Heidel)

Mica SchistBecause quartz is visible in the sample, this particular mica schist could also be called quartz mica schist.

Schist is a metamorphic rock.

Mica schist can be noted by its:Metallic luster

Fissility

Softness

Close-up of mica schist (Photo by Kirsten Heidel)

Mountain ViewsIf we drive just a mile or two farther past the mica schist, we can see some spectacular mountain views. The Rocky Mountains were formed by lifting and various ways of erosion.

Rocky Mountain view (Photo by Kirsten Heidel)

Mountain ViewsNotice the rounded ridges and peaks of the mountains. Thousands of years of erosion have softened many of the once ragged edges of the mountains.

In the far distance, we can also see arêtes, which were formed by glacial erosion.

Rounded ridges and peaks

Arêtes

Features of the Rocky Mountains (Photos by Kirsten Heidel)

Onward We Carry…Keep driving down Robinson Hill Road for 1.2 miles and turn left onto Smith Hill Road.

Follow Smith Hill Road all the way to Highway 119, which is 2.3 miles. Turn right onto the highway.

Continue on Highway 119 until you reach Blackhawk. If you’re 21, have a little fun before you go!

If you’re not 21, continue driving on Highway 119 and turn left on Gregory Street (2.7 miles from Smith Hill Road).

Follow Gregory Street which is about 1.1 miles and turn left onto Main Street.

After one block turn right onto Nevada Street which turns in Central City Parkway.

Take Notice of…There are several places on the way down Central City Parkway where walls of gneiss can be seen. Pull over at any of these spots. There is one about halfway down the parkway with enough room to pull over. Look at how large the gneissic banding is! Also notice the right angle cleavage.

Close-up of gneiss and gneissic banding (Photos by Kirsten Heidel)

Headed Home…Unfortunately, stopping to observe the granite was the last stop for our field trip.

Follow Central City Parkway down to I-70 east.

To return the way we came, take I-70 east and get off on exit 259. You will merge back onto Hogback Road.

If you would like to get back onto CO-470 instead, go 1 mile past exit 259 and merge onto CO-470.

If you choose to take Hogback Road, you can also stop at Red Rocks and Dinosaur Ridge.

Road Trippin’ Was AwesomeThe amount of miles driven in a round trip was about 98.1 miles.

Total driving time was about 2 hours and 45 minutes.

This road trip was amazing! We were able to observe some amazing points of geological interest and have some fun along the way.

There are innumerable roads that can be taken and other geological points of interest on this field trip that can be stopped at, such as Red Rocks. Make sure you bring plenty of gas money, though!

ReferencesAlden, Andrew. “Schist.” About.com. About.com, 2013. Web. 22 April 2013.

http://geology.about.com/od/rocks/ig/metrockindex/rocpicschist.htm

“Colorado, US.” The Paleontology Portal. National Science Foundation, n.d. Web. 22 April 2013. http://www.paleoportal.org/index.php?globalnav=time_space&sectionnav=state&name=Colorado

Google. Google Maps. Google, 2013. Web. 22 April 2013.http://maps.google.com/

Jones, Charles E., and Norris W. Jones. Laboratory Manual for Physical Geology. 8th ed. New York: McGraw-Hill, 2013. Print.

Plummer, Charles C., Diane H. Carlson, and Lisa Hammersley. Physical Geology. 14th ed. New York: McGraw-Hill, 2013. Print.

“The Rocky Mountains: The Natural History of the Rocky Mountains.” 8750. Mule Tools Inc., n.d. Web. 22 April 2013.http://www.8750.com/rockymtns.asp

United States. National Park Service. “The Dakota Hogback.” National Park Service. United States Dept. of the Interior, 2013. Web. 22 April 2013.

http://www.nps.gov/romo/dakota_hogback.htm

United States. U.S. Geological Survey. “National Water-Quality Assessment (NAWQA) Program.” United States Geological Survey. USGS, 2013. Web. 22 April 2013

http://co.water.usgs.gov/nawqa/splt/index.html