WATCHING FOR ROCKS Travels of a Sharp-Eyed Geologist: February 2012

Monday, February 27, 2012

Skiing Cedar Breaks

I’ve accomplished my winter 2012 weekend ski assault on the mountain and have returned home unscathed. 

On second thought, perhaps “assault” is a bit of a stretch.

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Tuesday, February 21, 2012

Music City Walkabout

I was in Tennessee recently, catching up with some old friends and revisiting some familiar sights. I have a 25–year history there, having lived in Knoxville for nearly 10 years and then middle Tennessee for 15 years.

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Shelby Street pedestrian bridge spans the Cumberland River near downtown Nashville

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Thursday, February 16, 2012

Back Road Into Town

If I stopped at every road cut I came across I’d never get anything else done. 

This is not necessarily a bad thing. 

Geological lollygagging in southern Utah can easily become a full–time obsession. More than many other places on the planet the geology here is utterly in your face, unencumbered by pesky vegetation, exposed for the entire world to see if that world would just take a few moments to look a bit more closely. 

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Tonaquint Drive road cut exposes an unconformable contact between Moenkopi and Shinarump deposits

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Friday, February 10, 2012

Summer Park Plans

I officially got the official word yesterday – I’ll be returning to Yellowstone National Park this summer.  

Woo Hoo!

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 Yellowstone Plateau with Grand Canyon of the Yellowstone River - view from Mt. Washburn


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Monday, February 6, 2012

Window Into A Microscopic World

Thin sections of rock only 0.03 millimeter or 0.00118110236 of an inch thick on a glass slide offer us incomparable insight into the geological history of our Earth. 

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Shearing textures in a garnet schist gneiss - crossed polarized view

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Friday, February 3, 2012

Mountains Under A Microscope

There are a lot of intriguing ideas and concepts in geology. Some are easier to wrap our minds around than others. One of the most phenomenal has got to be the idea that a 3 inch x 1 inch glass slide with a sliver of rock attached that has been sawed, sliced, glued and polished to a thickness of 0.03 millimeter can provide clues to the history of an entire mountain range. 

That’s 0.00118110236 of an inch of rock on a glass slide. Put under a special type of petrographic microscope and studied, this rock sliver or thin section can offer unparalleled insight not only to a mountain range but to the tectonic history of an entire continent.

Which means that knocking off a fist–sized piece of rock from someplace like this…

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Beaver Dam Mountains in southwest Utah

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