Callan Bentley is Associate Professor of Geology at Piedmont Virginia Community College in Charlottesville, Virginia. He is a Fellow of the Geological Society of America. For his work on this blog, the National Association of Geoscience Teachers recognized him with the James Shea Award. He has also won the Outstanding Faculty Award from the State Council on Higher Education in Virginia, and the Biggs Award for Excellence in Geoscience Teaching from the Geoscience Education Division of the Geological Society of America. In previous years, Callan served as a contributing editor at EARTH magazine, President of the Geological Society of Washington and President the Geo2YC division of NAGT.
Subscribe to Mountain Beltway
Ideas and opinions expressed on this site are those of the authors and commenters alone. They do not necessarily represent the views of the American Geophysical Union.
My guess is that like the oats in your cookie dough demonstration the orientation of leaves are stacked in a flat layer formation compressed by some natural force.
You got it!
The idea is that floodwaters imbricated these leaves into parallelism as it flowed. The same sort of alignment of tabular mineral grains (think micas in a schist) occurs when sufficient tectonic compression is applied to a rock.
Send me an e-mail with your address; and I’ll mail you the bumper sticker.
I was going to go more abstract with this one (and with very rusty memories of structural geology)–I saw the compressed leaves as an intrusion, with–and here’s where my memory gets hazier–a pyroclast to the upper left….
Fun exercise for the morning’s cup of tea, anyway!
Yep, I was going to guess foliated foliage as well.
and a not-quite Andy Goldsworthy work of art.
(you didn’t say it had to be the first person to respond)
I was going to try and come up with a play on leaf or leave, but that didn’t work.
Because you are particularly proud of those shoes and will be using them as a scaling device instead of the knife (which you have probably lost by now) from here on out? Or is this another great analog shot, like the one of the snow on your window? Either way I can’t wait! PS – what’s the best way to send you a picture? I have a shot of some mud cracks on a reservoir in eastern Oregon that I am certain would be of interest to you.
You’re funny, Eric! I like the crack about the knife. No, it’s not lost; you’ll see it again soon.
Yes, it’s an analogue, at least in my mind. Water flow in the stream imbricated these leaves against a rock, aligning them perpendicular to the flow direction. I was reminded of metamorphic foliation, which can align minerals like micas in an orientation which is perpendicular to the maximum principal stress direction.
You can send your mudcrack photos to me at [email protected] — and thanks!
Illustrating foliation with foliage? 😉
How about a leafslide? 😉