The Chugwater Formation

August 13, 2012

DSCF1210 (2) Chugwater

Photographer: Russell Losco; Russell's Web site  
Summary Author: Russell Losco

Pictured above is a striking outcropping of the Triassic Chugwater Formation. The Chugwater Formation, like many other formations of Triassic age is red because of oxidation of iron minerals within the rock. This formation is composed primarily of siltstones and durable, fine sandstones containing few fossils and is overlain by the Morrison Formation, which is famous for its dinosaur fossils. This outcrop, in the Red Hills, sometimes referred to as the Auburn Hills, of Wyoming is located on the north side of the Gros Ventre River valley. This is a classic U-shaped valley formed by glacial scouring that exposed this outcropping. The vantage point from which this picture was taken is atop a moraine left by the glacier. Picture was taken in August of 2007 while visiting the area on a field course on the geology of the National Parks of Wyoming.

Photo details: Camera Maker: FUJIFILM; Camera Model: FinePix A340; Focal Length: 5.7mm; Aperture: f/2.8; Exposure Time: 0.0008 s (1/1200); ISO equiv: 100; Exposure Bias: none; Metering Mode: Matrix; Exposure: program (Auto); White Balance: Auto; Flash Fired: Yes (Auto, return light detected); Orientation: Normal; Color Space: sRGB; Software: Adobe Photoshop 7.0.