Monday, September 22, 2014

9/20 Newberry National Volcanic Monument

This national park is relatively new, being founded in 1990.  It consists of several parts in this volcanic area that was formed when a rift developed 400,000 years ago.  Several minor volcanos and cinder cones can be seen in the area, but the largest was Newberry Volcano, a shield-type volcano that erupted about 75,000 years ago on an earlier caldera.  This area is still considered to be active, with possible eruptions in the future. 

Here is a site that explains some of the geology:  http://volcanoes.usgs.gov/volcanoes/newberry/newberry_geo_hist_81.html

I stopped first at the Lava Lands visitor center near the cinder cone.  This cone is NOT part of the Newberry volcano itself but is along the rift line. 



The hill in the distance is a cinder cone.  You can drive up in a personal car, but unfortunately they do not allow vehicles over 24'.  Darn.  Next time I will try to hitch a ride!

I drove another 20 miles to the Newberry volcano area.  This is one of the two lakes that fill the Newberry caldera. There are two lakes because a new cinder cone has built up between the two, as shown on the sign below.


I think one of the most interesting areas.  It is a flow of obsidian (glass) that was formed only 1,300 years ago. 

Obsidian is glass formed by intense heat melting sands inside the volcano.  I took the advice of the ranger and wore my loafers, the only closed-toe shoes I own, because of the sharp obsidian on the short trail to the viewpoint. 

The Native Americans used obsidian for spear points and tools.  The broken rocks are said to have a finer edge than even a surgeon's knife, and experiments show that surgery performed with tools made from these rocks result in finer scars.

The obsidian flow is huge!  You are not allowed to walk beyond the viewpoint, but I would not want to anyway.  It does not show in these photos, but the broken rocks were sparkling in the sunlight.

The outside of the rocks looks pretty much like other volcanic rocks, but when they are broken, you can see the glass-like interior.  This is a close-up of one broken rock.

Here is a large, broken boulder near the trail showing the outside and inside of the rock.

And another boulder!

You can see the pile of obsidian and part of the Newberry rim in the distance.

After my volcano visit, I headed off to Eugene, OR, about a three-hour drive. I took this photo of smoke from a forest fire in the distance.  I was lucky not to drive through smoke, however.   



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