A detailed examination of an elegant photo of the eastern front of California’s Sierra Nevada, from the perspective of the Alabama Hills. How many different geologic phenomena can be packed into a single image? Let’s find out!
The guest Friday fold comes to us from the Miocene of California, deposited in a releasing bend basin along the San Andreas Fault.
My friend Bill Burton (USGS, Reston) shared today’s Friday fold — Chevron folds in marble, Kings Canyon, California. Nice! Thanks for sharing, Bill!
Another week, another batch of new images produced on my home-based Magnify2 imaging system from GIGAmacro. Leptaena brachiopod in (Mississippian?) limestone from Montana: [gigapan id=”185784″] Link Here’s the flip side of the same sample, with a lot of fenestrate bryozoans to see: [gigapan id=”185809″] Link Fault breccia from the Corona Heights Fault of San Francisco: … Read more
Happy Friday – sorry to have not shared any folds with you last week. I hope these beautiful folds in Catalina Island meta-cherts will make up for it: As with the previous couple of Friday folds, this image is courtesy of Sarah Penniston-Dorland (University of Maryland, College Park).
Happy Friday! Here’s another fold from Catalina Island, California – an antiform in metasediments, courtesy of Sarah Penniston-Dorland of the University of Maryland:
My friend Sarah Penniston-Dorland, of the University of Maryland, supplied this week’s Friday fold. it comes from Catalina Island, California, where Sarah just wrapped up some field work with two of her students. All three of them have given me permission to post the images here: The Catalina Schist is a suite of subduction-related metamorphic … Read more
The week before the AGU Fall Meeting, San Francisco experienced heavy rain and strong coastal wave action. These two phenomena liberated a big boulder of serpentinite on Marshall’s Beach. As it moved downhill, it opened up a scarp with views into the colluvial soil horizons.
South of the Golden Gate Bridge in San Francisco, there are beachside exposures of serpentinite mélange: tectonically sheared-out former oceanic crust accreted to western North America as part of an accretionary wedge.
At the end of the AGU Fall meeting, Callan visits the Corona Heights “mirror” fault, renowned for its gorgeous slickensides. Explore the site in photos in GigaPans.