Sunday, January 13, 2008

Picture of the Day

So what happened here? This is a stop on our eastern Sierra Nevada field studies course. It is on the road to Black Butte on the north shore of Mono Lake. The sediments are muds and ash fall units, and are probably only a few thousand years old. The site is about 2-3 miles west of the Sierra Nevada frontal fault system. Our students spend some time sketching and hypothesizing how these sediments might have formed.

3 comments:

The Lost Geologist said...

Are those load-casts? I always dislike doing "telediagnosis" but to me it seems like the underlaying light-gray layer hasbeen squeezed out. Maybe also because of "volcanic bombs"?

Would syn-sedimentary faulting too far fetched?

Would be cool to know the answer. Too bad I won't be able to come by and take a look myself.

MJC Rocks said...

Thanks for paying a visit to my site! It is my understanding that these are liquefaction features, which makes sense, given the nearby active faults, and saturated ash and mud layers. It is a great outcrop for teaching purposes.

The Lost Geologist said...

Now that you mention it, it makes sense but those were buried very deep in my memory. :(