Multiple exposures of the Turtle Cove strata can be seen at Blue Basin in John Day National Monument. This blue-green rock layer represents millions of years of volcanic ash accumulation. Surprisingly enough, the green tint is not due to copper, but rather a complex blending of the elements hydrogen, oxygen, sodium, magnesium, aluminum, silicon, potassium, calcium, iron, strontium, and barium.
Capture Date: May 25th, 2009
Camera Settings: ISO 100, 17mm @ f/16, 6.0 sec