Geology and Paleontology

The exposed layers of massive Calico Bluff

NPS Photo by Josh Spice


Geological features within the preserve reveal a nearly continuous record of the floral, faunal, and tectonic history of east-central Alaska. The geology of the region also reveals fossil-bearing rock and sedimentary deposits that help scientists to track changes in the earth millions of years ago.


Geologic Processes

Movement along the Tintina Fault, of of the great fault systems in western North America, revealed the gold deposits that ignited the famous Klondike Gold Rush.


The preserve contains an uninterrupted sequence of fossil-bearing sedimentary rocks and some of the oldest known microfossils in existence have been found in this area.

Sedimentary Record

Sediments in bluffs along the Yukon River span some 700,000 years and displays the evolution of this river system through multiple glacial episodes.

Research and Education

The preserve provides opportunities to study geological and paleontological evidence of changing climate, landscapes, and ecosystems.


Last updated: August 19, 2016

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Mailing Address:

P.O. Box 167
Eagle, AK 99738


(907) 547-2233

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