Centennial Range The entire Centennial Range is seen looking south. The Refuge is roughly from the center of the image to the right, westerly.

Click the image at left for a detailed panoramic version.
Ancient Seas and Earth

The Centennial Mountains rising above Red Rock Lakes National Wildlife Refuge display over 500 million years of geologic history. But that history had little to do with creating the mountains here.

Volcanism and Earthquakes

Volcanic action was responsible for creating the Centennial Mountains, yet you'll find no Volcanos or geysers in the Centennial Valley.

Glaciation and the Ice Ages

Glaciers shaped the Centennial Valley peaks but today you won't find a glacier anywhere here. The last ice age here was over 10,000 years ago and there's no prospect of another one in the foreseeable future.

Weather and Erosion

Today, the most active agent in shaping the mountains is the weather and its erosional effects. Small creeks, rivers, lakes, wind, rain and sunshine shape the Centennial Mountains and Valley today. Red Rock Creek is the major feature for the drainage of Centennial Valley.

Red Rock Creek presently starts out from the slopes of Jefferson Peak through Hell Roaring Canyon as Hell Roaring Creek, then into the valley as Red Rock Creek, through the Upper and Lower Red Rock Lakes thence to the Lima Reservoir as Red Rock River on the far west of the valley. From here it flows into the Beaverhead River, and at the confluence of the Big Hole River to the Jefferson River, and finally into the Missouri which forms at Three Forks, MT. It has been measured as the most distant contribution to the length of the Missouri River (3,745 mi) making it the source of the longest river system in North America and the fourth longest in the world. Several thousand years ago, it actually ran a different course, draining to the Madison River through Elk Lake and a series of other lakes to the north. Volcanic and earth movements caused this path to be raised and closed off creating the current route through the valley. This water system provides a lot of the water for the meadows, marshes, wetlands that nourish the unique plants, birds and animals that live here.
Red Rock Creek

Using an interactive tool, explore the features of the Centennial Valley and surroundings using Google's Earth and Map database. Its fun and easy to use. Also, while visiting the other sections, click on the Google Earth Icon Google Interactive Viewer to see a specific feature on the map that is discussed in the text (you'll need Google Earth Plug-in for your browser.)

Painted Milk Vetch

Refuge Geologic Slideshow

Enjoy viewing images of the Red Rock Lakes National Wildlife Refuge geology and surrounding area with our slideshow. Click HERE to view the slideshow.

Start The Geology Tour

Use the FEATURES pull-down menu above to start exploring more of the Red Rock Lakes National Wildlife geologic features and geologic history. Use the PHOTO GALLERY to view examples and explore specific features using the GOOGLE MAPS menu item. You can also click HERE to continue the tour.


Glaciers shape the valley