8 December 2010

Focusing on S-C fabrics

Posted by Callan Bentley

Today’s geology word (according to Evelyn) is “fabric.” I spent a little time this afternoon playing with my ultra-cool Nikon microcamera, and decided to photograph the S-C fabric in one of the rock samples I collected in Turkey.

Because the microcamera is powerful, its plane of focus is very fine. As a consequence, slightly higher “elevation” parts of the rock sample are in focus at one notch, and slightly lower at the next notch. So I shot a bunch, changing the focal depth slightly for each snapshot, and then I stitched them together into this animated GIF…

Pretty cool effect, right?

“C” surfaces are more or less oriented to the horizontal edge of this image. “S” surfaces dip from upper left towards lower right. Sense of shear would be sinistral (top to the left).

What uses can you think of for animated GIFs like this in geology? I’ve got some ideas, but I’d love to hear what you think.

UPDATE: Here’s a slower version: