Geomorphology

Introduction

Garden of the Gods is one of the most spectacular places people can visit in Colorado Springs. One of the most spectacular experiences is just driving there. As you approach Garden of the Gods, you see mainly hills with grasses and trees, and then all of a sudden, out of nowhere, you drive around a curve, and see massive red rock structures.

Typical red rocks at Garden of the Gods.

To help people understand Garden of the Gods, we have to understand the geologic age of this site. The history of Garden of the Gods dates back to .01 million of years ago before the present (MYBP). That is not very old, but we also need to understand the eras of what formed it. It all started 1 billion years ago when the Pikes Peak granite was formed. The formations in the park were formed between 600 million years ago and 180 to 225 million years ago. Rocky Mountain Trough was initiated, and a restlessness and early mountain uplift in the Rocky Mountain Trough, Lyons. Later, a major period of mountain building begins as the Ancestral Rockies develop. Fountain Formation is deposited as alluvial fans along flanks of mountains, Sandstone and Lyons Formations were deposited, and the Ancestral Rockies were completely eroded and buried under their own debris. After this was the Jurassic period which is dated back 150 million years ago. 

In 1886, the skull of a Camptosaurus was found in this formation within Garden of the Gods. Going back to the history, during the Jurassic period, the Morrison Formation was deposited in tropical lowlands. From 135 to .02 million of years ago various mountain building, extinctions and periods of glaciation occurred. Then .01 million of years ago, erosional forces shaped Garden of the Gods (Garden of the Gods Geology, 1). 

Attraction
Of particular interest here are the scenic views of red sandstone formations, which include a balancing rock, and kissing camels. As well as, wonderful views of Pikes Peak, a large number of paved and unpaved hiking trails, the historic Rock Ledge Ranch Historic Site, rock climbing, mountain biking, guided outdoor educational tours, horseback riding, and a living history museum.

Overview
The landscape has an extensive amount of vegetation, cliffs, and various rock formations. Some of the particular types of vegetation found here are native grasses, bushes, ponderosa pine trees, cactus, and yucca. The cliffs and rock formations include both red and white sandstone that can be seen miles away. 
Throughout the landscape, steep and flat areas are found as well as thick and thin vegetation areas. Almost everywhere trees and bushes are seen. There are even pine trees seen growing out of rocks that are near the top of the rocks. 

Vertical red rocks supporting large trees near back of Kissing Camels.

Another image of trees growing from the rocks

 

Geomorphic Processes
Some visitors go to just take pictures; others go to see the various geologic processes that have occurred. To better explain the weathering and erosion processes, we must first look at what types of rocks are found here. Beginning in the western portion of Garden of the Gods, we would find the oldest types of rock. As you travel eastward, the rocks become younger. The oldest rock found is Fountain Arkose, which are very coarse-grained sediments. This type of rock layer is present in the Balanced Rock, Siamese Twins, Cathedral Spires and Three Graces.

Balanced Rock

Three Graces Cathedral Spires

The second type of rock found is Lyons Sandstone. It is made up of fine-grained quartz sandstone and its deposits are seen in various directions called cross bedding. Cross bedding is found among meandering stream deposits, sand dunes and beaches. Some places where this type of rock is found are the Kissing Camels, South Gateway Rock, Cathedral, and the Sleeping Giant.

Kissing Camels (front)

Kissing Camels (back) Sleeping Giant

The third type of rock found is Lykins Formation. This type of rock consists of red, thin-bedded, sand siltstones and shales and is where one may find fossil algae formed in a marine environment (Glossary for Garden of the Gods Geology, 1-2). 

The fourth type of rock found is called Morrison Formation. It is made up of clays, siltstones, and carbonates. The fifth type of rock is Purgatoire Formation. This formation is made of ?bleached? sandstone, shale, and siltstone and the deposits are thought to have been from a flood plain environment. The sixth type of rock found is Dakota Sandstone which is also marine sandstone. It was probably deposited near or on a beach like environment. The seventh type of rock found is Benton Group. It was a result from a shallow sea that ran over the beach sands. It consists of shale and limestone which is found all over Garden of the Gods. The soft shales can easily be eroded and due to erosion, it has formed the valley west of Rock Ledge Ranch. The eighth type of rock found is Niobara Formation. It is primarily made up of limestone and marine fossils. The youngest type of rock found is Pierre Shale. It lies above the Niobara Formation and is the thickest formation found in Colorado Springs. In this formation, clams, ammonites and bones of fossil fish can be found (Glossary for Garden of the Gods Geology, 2). 

Erosion and weathering processes that take place at Garden of the Gods have created all of the landforms seen in this park. When rock material weathers and erodes, it creates a depositional landform. The Lyons Sandstone was originally deposited into dunes. As more sediment is buried on top of these dunes, it solidifies and later exposes a process of erosion called erosional landforms. Each layer of rock was eroded away differently called differential erosion. Differential erosion is defined as ?selective removal of rock material in accordance to erosive susceptibility and agency? (Glossary for Garden of the Gods Geology, 3-4). This means that the rocks material?s hardness is related to its ability to withstand the erosive forces of wind, water and ice. An example of this type of erosion is mudstones vs. sandstones. The mudstone erodes more easily than the sandstone (Glossary for Garden of the Gods Geology, 3-4).  

Sentinel Rock.  Notice the weathering of the rock.

Layering in the rock

Several natural process continue to shape the park.  The first is faulting.  Faulting is a result of stress in the strata layers during the Laramide Orogeny. Faulting is one of the most active processes because it breaks large pieces of rock into smaller rocks without having to shed layer by layer. In addition to faulting, which tends to break up rocks, several weathering processes continually break down material.  Weathering processes in the park include the shedding of a case-hardened rock surfaces, including weathering rinds; the excavating of the relatively soft interior of cavernous features (called tafoni); and freeze and thaw processes (frost shattering).  (Glossary for Garden of the Gods Geology, 3). 

Fissures caused by weathering

Various weathering forms on South Gateway Rock

Another important component involved with the shaping Garden of the Gods is the local climate.  Though the park resides in a semi-arid climate, the fins and outcrops create microclimates that favor, in some cases, rapid weathering and erosion.  However, if the park were located in a more moist climate, the landforms would probably be covered with vegetation and thick soil cover (Glossary for Garden of the Gods Geology, 4).

Hazards
As with any place anyone goes to, hazards are always going to occur. The most dominant hazard to watch out for is rock falls or rock slides. Due to all the weathering and erosion occurring at Gardens of the Gods, people should watch out for rocks that may fall as they are walking and/or driving.

Image of rocks that have fallen.  Notice size..

Another hazard that is specifically for rock climbers is the possibility of weakened sandstone from moisture.  Rock climbers should stay away from any visibly wet rock that may crumble while climbing. More hazards that should be considered when going to Garden of the Gods are wildlife, extreme weather, and tripping/ falling on or off rocks.  For wildlife, mountain lions and bears are seen.  For extreme weather, lightning, flooding, and blizzards can occur.  The last hazard that is always possible in any instance is getting lost. Be sure to have a map with you at all times.  They can be picked up at the visitor?s center.

Restrooms at main parking lot.

Provide restroom number to emergency responders

These are the restrooms found at the main parking lot. Notice the address on the side of the building. This is used in emergency cases. All the caller has to say is the address their and the operator knows where in the park the person is.

References
Garden of the Gods, Garden of the Gods Geology. City of Colorado Springs. 2007. 5 Nov. 
Garden of the Gods, Important Events in Garden of the Gods Geology. City of Colorado Springs. 2007. 26 Nov. 

Driving Directions and Google Earth .kmz File

Google Earth Placemark File (.kmz) file: link

Driving Directions to Garden of the Gods Visitor Center and Parking Area:

1. Take the Garden of the Gods Road/Austin Bluffs Blvd. exit off of I-25
2. Take Garden of the Gods west 2.9 miles
3. Turn left (south) on N 30th St. Continue 1.7 miles
4. Visitor's Center is on left (east) side of N 30th St