Forming a Pinnacle
The Dillon Pinnacles are one example of many spires found within Curecanti. Pinnacles are a product of erosion. Wind, rain, and ice are carving away at the landscape. This process happens everywhere, so why does the rock here form pinnacle shapes? The answer lies in rock hardness.
When the erosive forces hit this hillside, the underlying weaker rock wears away rapidly. The more resistant tuff forms a cap of rock on top. The cap rock helps protect some of the rock immediately beneath it, while the surrounding rocks are worn away. A spire or pinnacle forms. Eventually, the tuff on the pinnacle will erode as seen on many of the pinnacles here that are missing a cap.
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West Elk Breccia, a soft rock composed of ash and volcanic rock chunks.
Blue Mesa Tuff, a hard rock that serves as a cap.
Erected by National Park Service.
Topics. This historical marker is listed in this topic list: Natural Features.
Location. 38° 27.914′ N, 107° 15.851′ W. Marker is near Gunnison, Colorado, in Gunnison County. It is on U.S. 50, on the right when
this page online
Regionally, this marker is in the Colorado High Rockies. It is also in the American Mountain West. Globally, it is in North America, the Rocky Mountains, the Western Hemisphere, the Western World, and the Anglosphere.
Other nearby markers. At least 8 other markers are within 12 miles of this marker, measured as the crow flies: If You Only Knew (here, next to this marker); Wayne N. Aspinall (approx. 2.2 miles away); Crossing the Canyon (approx. 2.2 miles away); Trains and Trout (approx. 3½ miles away); Storage Units (approx. 4.4 miles away); Puzzle from the Past (approx. 5.3 miles away); a different marker also named Trains and Trout (approx. 8.4 miles away); Saguache and San Juan Toll Road (approx. 12.1 miles away). Touch for a list and map of all markers in Gunnison.
Also see . . .
1. Curecanti National Recreation Area Natural Features & Ecosystems.
2. Pinnacles National Park Geology. (Submitted on October 28, 2020, by William Fischer, Jr. of Reynoldsburg, Ohio.)
Credits. This page was last revised on October 28, 2020. It was originally submitted on October 28, 2020, by William Fischer, Jr. of Reynoldsburg, Ohio. This page has been viewed 560 times since then and 27 times this year. Photos: 1, 2. submitted on October 28, 2020, by William Fischer, Jr. of Reynoldsburg, Ohio.
