Riding a skinny horst
I have shown you tafoni/metate photos from this site, and I have shown you petroglyph/meander photos from this site. But I have not yet shown you the real reason that field forum leader David Ferrill brought us out to the site. Hopefully this picture will convey some of the structural wonder of this location:
You're looking down the axis of a horst, a normal-fault-bounded block of rock that has had normal-fault-bounded blocks of rock slide downward on either side of it (called grabens, from the German for "grave"). The collection of automobiles provides a sense of scale: this is a pretty skinny little horst.
In miniature, this site shows the processes that are playing out on a larger scale in the Owens Valley (itself a graben), the White Mountains (a horst), and the Basin & Range province in general.
I used Photoshop to stitch together a panorama looking along the graben marked "#1" in the annotated photo above:
(Click here for a BIGGER version.) That's the Sierra Nevada in the distance, and the Owens River at far left, with the skinny horst at the far right. I like how you can see some of the welded "Ig2" layer right where the graben meets Chalk Bluff (far left), while it's buried beneath sediment in the rest of the valley. That same layer is the resistant one that caps the horst (atop which I took the photo).
I'm not sure I had ever consciously stood atop a horst before. Yeehaw. Giddyap!
You're looking down the axis of a horst, a normal-fault-bounded block of rock that has had normal-fault-bounded blocks of rock slide downward on either side of it (called grabens, from the German for "grave"). The collection of automobiles provides a sense of scale: this is a pretty skinny little horst.
In miniature, this site shows the processes that are playing out on a larger scale in the Owens Valley (itself a graben), the White Mountains (a horst), and the Basin & Range province in general.
I used Photoshop to stitch together a panorama looking along the graben marked "#1" in the annotated photo above:
(Click here for a BIGGER version.) That's the Sierra Nevada in the distance, and the Owens River at far left, with the skinny horst at the far right. I like how you can see some of the welded "Ig2" layer right where the graben meets Chalk Bluff (far left), while it's buried beneath sediment in the rest of the valley. That same layer is the resistant one that caps the horst (atop which I took the photo).
I'm not sure I had ever consciously stood atop a horst before. Yeehaw. Giddyap!
Labels: california, faults, rift valleys, structure, travel
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