Saturday, January 10, 2015

Geo 1095: January 10, Day 740: Shady Cove

Looking over the shoulders of Bob Lillie, OSU Emeritus Professor of Geology (Geophysics), and that of his wife, we get our first look into the deep cove behind North Falls. There's a distinct dark layer of sediment deposited between two massive flows of the Grande Ronde Basalt of the Columbia River Group. It forms the deepest recess here. Above that is a lighter band, which is also clearly sedimentary in origin, but appears to have been slightly to heavily contact metamorphosed as it gets closer to the contact with the overlying basalt. This explains the ramping outward from the dark strata: the rock is getting progressively tougher upward toward the contact. What's difficult to grasp in this photo, though, is a sense of scale. Looking carefully at the full-size version, I don't spot any people in this shot, but we'll have some in days to come.

Photo unmodified. August 30, 2012. FlashEarth Location (approximate).

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