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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:
10 June 2016
Green River Formation stromatolite – a virtual sample
Today concludes a weeklong run of virtual samples. For the past five days, I’ve been presenting examples of a visualization combination that leverages the advantages of the GIGAmacro system with the 3D ‘virtual sample’ perspective of the Sketchfab-hosted model: the same sample presented in both formats. Today, we finish up with a stromatolite from the hypersaline Wilkins Creek member of the Eocene-aged Green River Formation of southwestern Wyoming: Link GIGAmacro by …
16 April 2015
Eocene dike and sill in Ordovician limestone
A virtual field trip to a quarry in far western Virginia, showing anomalous igneous intrusions (a dike and a sill) of Eocene age cross-cutting early Paleozoic carbonates.
8 April 2014
Deformation associated with the intrusion of the Muleros Andesite
Yesterday, I showed off a few views of the contact between the Cretaceous aged Mesilla Valley Formation shale and the hypabyssal Muleros Andesite which intruded into it during the Eocene at Mt. Cristo Rey (on the US/Mexico border where Texas meets New Mexico). Today, I’d like to look at some of the structure associated with the contact zone. First off, take a look at this image, which is looking orthogonal …
7 April 2014
Contact between Muleros Andesite and Mesilla Valley Formation shale at Mt. Cristo Rey
There are two rock units in this photo. One is igneous, one is sedimentary. Can you find the contact between them? It’s somewhere along this dashed line… The Mesilla Valley Formation is Cretaceous shale with some sandstone. The Muleros Andesite (pretty much identical to the Campus Andesite you find at UTEP) is Eocene. Here’s a closer, more precisely-constrained, look at it: …but that one is in the shade. It’s bolder …
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 …
25 December 2012
Stromatolites of the Green River Formation
The summer before last (2011), I spent some time in Wyoming on an energy resources field trip run by Sheridan College, and one stop we made was to look at “oil shale” (really kerogen-rich marlstone) of the Green River Formation, an Eocene lake deposit in southwestern Wyoming. The oil shale is exposed on the east side of the White Mountain escarpment in the Green River Basin. Here’s the view to …
11 December 2012
Why Geology Matters, by Doug MacDougall
Callan reviews a new book by Doug Macdougall: “Why Geology Matters.”
20 June 2012
Pebble Creek memories
This summer is the first summer in half a decade that I won’t be spending time camping at Pebble Creek campground, in the Lamar Valley of northeastern Yellowstone (“America’s Serengeti”). While I’m very excited to be nesting and exploring my new home in the Fort Valley, it does make me a bit wistful to think I won’t be waking up to see this lovely sight this year: That’s morning light …
10 April 2012
Macro GigaPans of Florissant insect fossils
Today, for your viewing pleasure, please check out five macro GigaPans of insect fossils from the Florissant fossil beds in Colorado (34.07 +/-0.10Ma). These amazing specimens were collected by Joe Cancellare, a student working on research supervised by Josh Villalobos of El Paso Community College in El Paso, Texas. Our M.A.G.I.C. project is helping Joe and Josh out by producing macro GigaPans for them. link link link link link All …
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.