Steens Mountain Vista

August 17, 2015


Photographer: Kathleen Kiefer
Summary Author: Kathleen Kiefer

The treasured landscape of the Pacific Northwest contains evidence of some of the youngest geologic activity on the North American continent. Southeastern Oregon's Steens Mountain is a perfect example. How fortunate that for my first visit to this beautiful place, we had perfect weather. Plus smoke from nearby wildfires remained mostly to the west.

About 17 million years ago, staggering amounts of lava flowed episodically to depths of over 100 ft (30 m). The stacking of one layer upon the next over the ensuing eons formed Steens Mountain, the largest fault-block mountain in the Great Basin. Massive internal pressures forced the east edge of the Steens upward. The result was a 30 mi (48 km) long fault-block mountain with a spectacular and rugged east face that rises one vertical mile above the Alvord Desert.

During the last Ice Age, glaciers formed four different stream channels on the mountain, gouging trenches almost a half mile deep through layers of basalt. Each of the four huge U-shaped gorges is visible along the 63 mi (100 km) Steens Mountain Loop.

The image above was taken at an elevation of about 9,540 ft (2,910 m), looking eastward towards the salt flats of the Alvord Desert, the light beige oval-shaped landscape in the distance. The rugged basalt outcrops visible in the middle and middle left are Steens Mountain Basalt. Note the Steens Mountain Thistle visible on the left side of the photo. Though not rare, it's endemic to Steens Mountain.

Photo Details: Camera: Canon EOS 5D Mark III; Lens: EF24-105mm f/4L IS USM; Focal Length: 24mm; Focus Distance: 3.39m; Aperture: ƒ/22.0; Exposure Time: 0.010 s (1/100); ISO equiv: 200; Software: Adobe Photoshop CS5.1 Windows.