Colorado’s Abundance ofGeological WondersAdventureA field trip filled with fun real-lifeobservations of Colorado’s geologicalwondersBy Kirsten Heidel
Trip DetailsOur trip will begin near the south entrance of Chatfield State Park. Wewill be traveling northwest passing through Morrison and takingHighway 36 into the Rocky Mountains.Along the way we will be making several pit stops to observeinteresting geological points.Be sure to bring snacks, drinks, and good music. This trip will take afew hours. If you’re 21 or older, there will be an opportunity to gogambling at Blackhawk. So bringing some extra cash is a good ideatoo.Let’s get started!
Ready, Set… Go!Our trip will begin in theparking lot located near thesouth entrance of Chatfield.It is at the intersection ofN. Roxborough Park Roadand the highline canal.Drive south 1.6 miles andturn right onto Titan road.Titan road will turn intoRampart Range Rd. at alarge curve. FollowTitan/Rampart Range for2.5 miles until you reachWaterton 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 Watertoncanyon 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 StatePark (Photo by Kirsten Heidel)
The South Platte RiverThe South Platte Riverfeatures high and slowvelocities due to theconstant change of shapeand roughness of thechannel.The river also featuresseveral sand and gravelbars in the middle of theriver and on its banks.Some of these sand andgravel bars are point bars.The South Platte Riverfeeds the South Platte RiverBasin pictured to the right.The South Platte RiverBasin is prone to flooding.In order to decreaseflooding, dams, spillways,and canals (such asChatfield Dam and theHighline Canal) were built.Map of the South Platte River Basin (U.S. Geological Survey)
Destination ReachedMerge right onto S. Wadsworth Blvd. Drive 4.4 miles until you reach CO-470. TakeCO-470 west (turn left).Drive 9.4 miles until you reach the Morrison exit. Take the exit and turn left ontoMorrison 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 onboth sides of the street. Hopefully it won’t be a busy day so parallel parking will beeasy.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! Allpaths lead to the top of the hogback so pick the path that is mostappealing to you.On your way up, be sure to look for old snail shells and observe someof 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 isobvious by the rounded cobbles and pebbles.The conglomerate rocks also formed in the sea. Ocean waves rounded the cobblesand pebbles (Plummer, Carlson, and Hammersley 143). Later, the soil settled andsolidified 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 ofthe mountain you canobserve the rocks anddetermine what they are.The top layer of rocks aredakota sandstone(National Park Service).In the photo to the right,we can see how plantscontribute to themechanical weathering ofthe sandstone. As the rootsgrow into the cracks of therocks, the cracks expand.Layer ofDakotaSandstone(Photo byKirstenHeidel)Pine treerootsgrowing intothesandstone(Photo byKirstenHeidel)
Reaching the TopStriations are one of the mostnotable feature of the dakotasandstone atop the mountain.Striations in some fallen dakota sandstone(Photos by Kirsten Heidel)
Reaching the TopAnother notable feature is the cleavage of thesandstone. The pictures to the right show twodirections of cleavage.The picture below shows one direction ofcleavage.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 safeplace to rockclimb… do it! Butmake sure youhave a friend withyou just in casesomething goesawry.The views ofMorrison andBandimereSpeedway arespectacular. Photoshere would makegreat Facebookprofile pictures! Photos by Kirsten Heidel
Onward We Carry…After carefully climbingback down the hogback,we’re hopping back intothe car and continuing tofollow Mt. Vernon Ave.This will eventually turninto Hogback Rd.Follow Mt. VernonAve./Hogback Rd. For 3.2miles.Turn right into theStegosaurus lot.Stegosaurus Parking Lot (Photo by Google Maps)
Hogbacks Are Like OnionsTake the trailhead at the north end of the parking lot. Follow this trailaround the hogback until you are parallel with the highway and cansee the layers of sediment. This area is also the Dakota Hogback.Layers of shale and limestone (Photo by Kirsten Heidel)
Hogbacks Are Like OnionsLayers 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 theof layers of sediment which lay beneath our feet.The top layer is dakota sandstone, followed by limestone, and finally acouple of types of shale (National Park Service).The hogback was formed as colliding plates lifted and pushed up theland.Close-up view of one of the layers of shale (Photo by Kirsten Heidel)
The Dakota HogbackWe can see that rockslidesand rockfalls occur on thisside 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 layeredhogback, it is time to get back in the car.Turn right out of the parking lot and continue on Hogback Road. It willeventually 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 6thAvenue. 6thAvenue eventually turns into Highway 93 north.After following Heritage Road/Highway 93 north for 3.7 miles, turn leftonto Golden Gate Canyon Road.
Take Notice of…Sometimes human impact in geology can be beneficial, especially when itcomes to harmful mass wasting. Along several parts of Golden Gate CanyonRoad, 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 HillRoad. Turn left.Notice how the rocks along Robinson Hill Road display the same typeof 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 outcropof rocks on the right side of the road. The outcrop of rocks, which ismica schist, is your geological pit stop.Outcropping of mica schist along Robinson Hill Road (Photos by Kirsten Heidel)
Mica Schist with QuartzA large chunk of quartz foundin the mica schist.Close-ups of mica schist (Photos by Kirsten Heidel)
Mica SchistBecause quartz is visible in the sample, this particular mica schistcould also be called quartz mica schist.Schist is a metamorphic rock.Mica schist can be noted by its:Metallic lusterFissilitySoftnessClose-up of mica schist (Photo by Kirsten Heidel)
Mountain ViewsIf we drive just a mile or two farther past the mica schist, we can seesome spectacular mountain views. The Rocky Mountains were formedby lifting and various ways of erosion.Rocky Mountain view (Photo by Kirsten Heidel)
Mountain ViewsNotice the rounded ridges and peaks of the mountains. Thousands ofyears of erosion have softened many of the once ragged edges of themountains.In the far distance, we can alsosee arêtes, which were formedby glacial erosion.Rounded ridges and peaksArêtesFeatures 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 SmithHill Road.Follow Smith Hill Road all the way to Highway 119, which is 2.3 miles. Turnright onto the highway.Continue on Highway 119 until you reach Blackhawk. If you’re 21, have alittle fun before you go!If you’re not 21, continue driving on Highway 119 and turn left on GregoryStreet (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 CityParkway.
Take Notice of…There are several places on the way down Central City Parkway where wallsof gneiss can be seen. Pull over at any of these spots. There is one abouthalfway down the parkway with enough room to pull over. Look at how largethe 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 fieldtrip.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 willmerge back onto Hogback Road.If you would like to get back onto CO-470 instead, go 1 mile past exit 259 andmerge onto CO-470.If you choose to take Hogback Road, you can also stop at Red Rocks andDinosaur 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 amazingpoints of geological interest and have some fun along the way.There are innumerable roads that can be taken and other geologicalpoints of interest on this field trip that can be stopped at, such as RedRocks. 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§ionnav=state&name=ColoradoGoogle. 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.aspUnited 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.htmUnited States. U.S. Geological Survey. “National Water-Quality Assessment (NAWQA) Program.” United StatesGeological Survey. USGS, 2013. Web. 22 April 2013http://co.water.usgs.gov/nawqa/splt/index.html