Geomorphological evidence for a glacially-carved Fish Creek Canyon- Steamboat Springs, CO.

 

Fish Creek Canyon exhibits evidence of its formation history:

  1. Regional-scale topographic comparisons to Northern Rockies
  2. Glacier-valley scale topographic comparison to Canadian Athabasca Glacier
  3. Landform and sediment deposit analysis

A modern analog for the Glacial Topography of the North Park Range is the Glacier National Park near the US – Canada border.  The google earth map (left below) shows the wide, – U-shaped valleys north of the road – Hwy 89. South of Hwy 89, the mountainous areas are cut by V-shaped valleys.  This indicates that the glacier growth was/is more prominent to the north.  Similarly in the North Park Range of Colorado, the significant glacier growth and glacier valley development occurred in the Zirkel Wilderness area.

Comparison between Northern Rocky Mountain Topography and North Park Mountain Range Topography.

Comparison of 3D image of the Athabasca Glacier in the Canadian Rockies to Fish Creek Valley of the North Park Mountain Range (near Steamboat Springs)  Erosion updip – to the top center of images, deposition downdip – bottom, center of the images.  The images are at the same scale. Although the Athabasca Glacier valley is significantly larger scale, certain shapes of features are similar.

Comparison of the famous Athabasca Glacier (Canadian Rockies) to the Fish Creek Valley of the North Park Mountain Range (Southern Rocky Mountains – US).  Fish Creek Valley is located in the Routt National Forest just outside city limits of Steamboat Springs, CO.

 

Geologists with the USGS have combined published information with field studies to describe, interpret, and document types of rocks and sediment in the Fish Creek valley and surrounding area.  Several types of glacial sediment and glacial landforms have been described, interpreted, and mapped (see the map below).  In general, the modern streams – Fish Creek and North Fork Fish Creek flow through hard rock (purple and white colors) material and glacial valley landforms.  The brown and green colors signify sedimentary deposits characteristic of glaciers.  The glaciers tend to erode from the updip area and deposit downstream or down-valley.  The FCF symbol on the map refers to Fish Creek Falls – the famous waterfall and tourist destination.  Fish Creek Falls is interpreted as a hanging valley or smaller glacial valley that contributed to the main glacial valley (in this case North Fork Fish Creek).

 

 

Steamboat Springs – Fish Creek Glacial Valley Geomorphological and Sedimentological Interpretation (modified from Atwood, 1937 and Snyder, 1978 ).