Fire & Ice EarthCache
-
Difficulty:
-
-
Terrain:
-
Size: 
(other)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
Rocky Mountain National Park is located west of Estes Park and north and east of Grand Lake. This is a fee area of the National Park Service, and costs $30 per vehicle. This fee is covered in the Rocky Mountain National Park Annual Pass, the Rocky Mountain National Park/Arapaho National Recreation Area Annual Pass, and the America the Beautiful Pass. Please see the following website (visit link) for the entire fee schedule. The park is open 24 hours a day, 365 days a year. Road and Trail Conditions and Closures can be found at: (visit link) Recorded information for the condition of Trail Ridge Road can be found by calling (970) 586-1222. Please remember that all geologic features within the borders of Rocky Mountain National Park are protected by law, as are all natural and historic features. Please do not disturb, damage, or remove any rocks, plants, or animals.
Parking for this EarthCache is at the Gore Range Overlook parking area off of Trail Ridge Road.
Your view to the west of this location is born of fire and ice. Fire for the volcanic origins of the northern portion of the Never Summer Mountain Range and Specimen Mountain, and ice for the glaciers that sculpted the landscape and the snow packs at the higher elevations, that to this day continue to work on eroding down the mountains.
Volcanism began here about 26 - 28 million years ago when magma rose close to the surface and there was a series of eruptions. The earth’s crust was being pulled apart in what was potentially a rift forming on a north/south line in what was to become Colorado and New Mexico. The rift failed, but not before pulling the earth apart enough to cause a series of eruptions. The eruptions of the Never Summer Mountains were included in these, and a large amount of ash was produced. The Never Summer Mountains, Specimen Mountain, and the rhyolite welded tuff at the Lava Cliffs were all produced from these eruptions.
Glaciation in this area is broken into roughly three “ages”: the pre-Bull Lake age of the middle & lower Pleistocene, the Bull Lake age of the upper & middle Pleistocene, and the Pinedale age of the upper Pleistocene. Later periods of glaciation tended to reshape the topography of earlier glacial periods, so it is not surprising that most of what can be seen from here was formed during the Pinedale Glaciation.
Mountain glaciers formed several distinctive topographic features during the time they were in existence. Cirques are bowl-shaped indentations carved out by the backward erosion of a small glacier into the mountain. As a glacier moves out of its cirque and down a valley, the glacier will widen and straighten what was once a V-shaped valley, into a steep-walled U-shaped valley. Backward erosion of two adjoining cirques can form a sharp ridge between them called an arête. Three or more cirques which form around a peak is a horn, and can be seen in the shape of Rocky Mountain National Park’s, Little Matterhorn. A terminal moraine is formed from the rock and till that remains after a glacier has retreated from the point of its furthest advance. A lateral moraine consists of the rock and till that was carried at the edges of the glacier. Many cirques will contain a small moraine from when the glacier made its final retreat.
To log this EarthCache, send me an email with the answers to these questions:
1.) List the 3 ages that glaciation has been broken into for this area.
2.) Count the number of U-shaped glacial valleys that you can see in the Never Summer Range.
Please consider posting photos of yourself, or the local geology, when you log this EarthCache. Photos can be an additional rewarding part of your journey, but posting them is not a requirement for logging this EarthCache, and is strictly optional.
The above information was compiled from the following sources:
2004. Rocky Mountain National Park. In Harris, A.G. et al., editors. Geology of National Parks, Sixth Ed. P. 337-356. Dubuque, Iowa: Kendall/Hunt Publishing Company.
Cole, J.C., and Braddock, W.A. 2009. Geologic map of the Estes Park 30’ x 60’ quadrangle, north-central Colorado: U.S. Geological Survey Scientific Investigations Map 3039, 1 sheet, scale 1:100,000, 1 pamphlet, 56 p.
Colorado Geological Survey. 2003. Messages in Stone. Matthews et al., editors. Denver, Colorado.
Raup, O.P. 2005. Geology Along Trail Ridge Road. A Self-Guided Tour for Motorists. Estes Park, Colorado: Rocky Mountain Nature Association.
Rocky Mountain National Park. Online at: (visit link)
Rocky Mountain National Park was most helpful in the background discussion, aid in the choosing of sites, and review of this EarthCache. My thanks to the Park for allowing the placement of this EarthCache!
Additional Hints
(No hints available.)