You are browsing the archive for December 2013 - Mountain Beltway.
31 December 2013
Pipkrakes in the yard
Asbestiform ice is growing in our yard this week, with individual ice needles several inches long… Note the substantial pebbles that have been lifted up by the growth of these things – they’re powerful little crystals.
30 December 2013
Monday macrobug: Earthworm!
I’m branching out with my macro”bugs” here – using the term sensu lato, to include all creepy-crawlies. Here’s a night crawler (Lumbricus terrestris), a non-native species of earthworm, that somehow found its way into our basement during a rainy period in late summer… He/she (worms are hermaphrodites) is long! I was astonished with a lengthy beast this was – and how did it fit through whatever little cranny it found …
27 December 2013
Friday fold: El Gordo slump(?) block
I ran out of folds last week, so earlier this week, I asked for help on Twitter. Laura Hamilton responded with a link to this image: @callanbentley El Gordo, S Spain. Huge turbidite block! Folded over as it moved over the seafloor 🙂 pic.twitter.com/L4INxmtLTq — lau.rah (@hammijam) December 23, 2013 Sweet. And you can’t complain about the exposure. Thanks, Laura! Happy Friday, all – last one of 2013!
26 December 2013
Mississippian invertebrates from the Lodgepole Limestone
On a cold winter’s day, Callan harks back to a summer’s afternoon fossilizing in the Rocky Mountains. A few choice images of Mississippian-aged marine invertebrates are shared.
24 December 2013
Ichnology of a one-horse open sleigh
On my morning walk earlier in the month, I encountered this trackway: Those are percheron (big breed of horse) hoof-prints, and the tracks of an authentic one-horse open sleigh, like the one invoked in “Jingle Bells!” Our neighbor, Don Warlick of Secret Passage Ranch, brings the sleigh out for neighborhood fun when conditions are right… Photo by Paul Kosubinsky (Click to enlarge) We had a blast tootling around on it …
23 December 2013
Monday macrobugs: mating stick insects
Back in the fall, we saw a lot of sexy scenes among the stick insects on our land. Everywhere, it seemed, the smaller males were searching out larger females, and put gametes together to make the little zygotes that would grow into the next generation of these extraordinarily well-camouflaged insects… Here’s a pair on the side of the house: And, same pair, with a flash illuminating their nuptials… Note the …
20 December 2013
Friday fold: Another from Cristo Rey
The laccolith of Cristo Rey, at the Chihuahua / Texas / New Mexico triple point, is host to some cool geology. It’s cored by the Campus Andesite (47 Ma, Eocene) but surrounding the intrusion are a slew of sedimentary rocks, include the Turitella-bearing limestones of the Buda Formation and the shales and sandstones of the Mesilla Valley Formation. My colleague and friend Joshua Villalobos of El Paso Community College in …
19 December 2013
New macro GigaPans of cool rock samples
It’s time to bring you up to date on some of the latest imagery produced by the Mid-Atlantic Geo-Image Collection. All of the following images were constructed by my student Robin Rohrback-Schiavone, on the GIGAmacro photographic imaging system in our lab… Several of the Precambrian samples came to us on loan from Jay Kaufman of the University of Maryland, College Park. Enjoy exploring some very cool rocks. Ball & pillow …
17 December 2013
Ice oddities
I took a walk through my neighborhood on a cold morning last week. I saw some neat features in the ice. Here’s a frozen backswamp next to Passage Creek (which lies in the tall trees just beyond the snow-covered natural levee… My neighbors (on whose land this backswamp can be found) had driven an ATV through the ice and water the previous day, and it had created a series of …
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.