You are browsing the archive for Callan Bentley, Author at Mountain Beltway.
17 November 2023
Friday fold: Floor paver in the Atlanta airport
On my way back to Virginia from Hawaii, I had a three hour layover in the Atlanta airport. There, I spotted this charismatic stone paver on on the terminal floor. It showed folds, and so I snapped a photo, but it also shows plenty more… An annotated copy: Happy Friday, all!
9 November 2023
Glacial geology of Discovery Park, Seattle
A field trip to examine the glacial geology of Discovery Park in Seattle, Washington, leads Callan to contemplate the nature of expertise — and especially his steep learning curve on an oceanographic cruise.
7 November 2023
Near-empty seas, near-empty air
Callan is currently at sea aboard the research vessel Thomas G. Thompson, crossing the North Pacific Ocean from Seattle to Honolulu. In this post, he explores a fascinating aspect of life on the high seas: there is shockingly little life! Explore the scant copepods and albatrosses and reflect on life in the oligotrophic open ocean.
3 November 2023
Friday fold: Neoproterozoic rhyolite (of the Konnarock Formation?)
The Friday fold returns!
Today we join the Virginia Geological Field Conference to look at primary volcanic flow banding in a Neoproterozoic rhyolite, and consider what it might have to tell us about the ancient Snowball Earth glaciations.
1 November 2023
Four new videos about east coast geology
Hi all! I’ve been putting my energy into video production more than blogging lately, but let me share some of that work with you:
15 September 2023
Friday fold: Candler Formation
On a birding hike yesterday morning, I found this: This is a little slab of kinked phyllite of the Candler Formation. This metamorphic rock started as mud (and ash) deposited atop the Catoctin Formation, and it was later squeezed and heated during Appalachian mountain-building, encouraging the growth of micas at the expense of clay. A strong differential stress made sure those micas grew in one preferred orientation, and that resulted …
8 August 2023
Three new videos from Montana
I spent several enjoyable weeks in Montana last month, and shot some new video content there for my YouTube channel. Here are three videos that may be of interest to readers of this blog:
5 August 2023
Bird update “July” 2023
Oops – July slipped by without a monthly bird update! Maybe that’s not the end of the world – I spent much of the month in Montana, and only tacked a few new species onto my county list – a Swallow-tailed kite, a Northern bobwhite, and a Great egret (photo above, 2nd column in the 2nd row). So for those keeping track, that puts me at 154, which is ranked …
28 July 2023
Friday fold/fauxld duet from Glacier National Park
When is an apparent anticline not an fold? Find out on this week’s edition of the Friday Fold…
14 July 2023
Friday fauxld: Sacagawea Cirque
Found this beautiful cobble while hiking Sacagawea Peak with my family yesterday, in Montana’s Bridger Range. It’s not actually folded as much as it appears to be; the laminations are slab like and nearly parallel to the surface in this photo, with the cobble surface sectioning them obliquely to produce this pattern.
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.