Encore - Weeping Wall in Saline Canyon

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Photographer: Thomas McGuire; Tom’s Web Page
Summary Author: Thomas McGuire

Within Earth systems, the most complex and active environments are generally at interfaces of the geosphere (solid earth), atmosphere and hydrosphere. It's at these interfaces that the biosphere is also most visible and dynamic. The photo above shows a north-facing wall of a remote canyon in the Saline Valley section of Death Valley National Park, California. This portion of the canyon face is approximately 33 ft (10 m) across with a slope of nearly 90 degrees. Saline Valley, in the rain shadow of the Sierra Nevada range, receives very little annual rainfall. However, water that sinks into the rocks can cause perennial springs and seeps along the deep canyon walls in this desert environment where surface water is otherwise scarce. Early inhabitants and explorers learned to depend upon water sources such as this. The colors of the wall are attributable to green photosynthetic plants such as moss and orange algae, as well as brown mineral staining that results from deep oxidation of the rocks catalyzed by groundwater. Blue areas may also be algae, and the whitish color is probably gypsum or another mineral washed out of the rock. Photo taken in October of 2005.

Related links:

• Vasey’s Paradise in the Grand Canyon
• Paleontological Research Institute; Canyons of the Southwest
  (Free Educational PowerPoints by this author)