Callan Bentley
2019 Yard List
New year’s day! For this blog and me, the first day of the year is time for the annual recap of birds seen on my land in Fort Valley, Virginia. Here are the previous iterations: 2012 (39 species) 2013 (51 species) 2014 (58 species) 2015 (65 species) 2016 (59 species) 2017 (56 species) 2018 (60 … Read more
Friday fold: blueschist & eclogite at Jenner, California
A pre-Fall Meeting field trip to the coast of northern California yields rare sights of garnet-bearing blueschist, plus eclogite, some pillow basalts, birds, waves, wind, and a lot of rain.
‘Streetcar 2 Subduction’ is live!
This week marks the launch of a new digital revision of a field guide to the geology of San Francisco, “Streetcar 2 Subduction.” Learn more here!
Friday fold: a secret Santa rock exchange gift!
I participated this year in the Secret Santa Rock Exchange, wherein I shipped out a mystery rock to a random person, and got back a mystery rock from another random person. What fun! My mystery rock has folds in it! It’s from Matt Bruseke at Kansas State University. Check it out: Matt writes that this … Read more
Friday fold: Noonday Dolomite in Mosaic Canyon
Because I’m putting together a field course for spring break 2020 to Death Valley California, I was looking through old Death Valley photos this week, from the last time I went to that special place. It was seven years ago! How time flies… This one is in Mosaic Canyon, and was taken by my student … Read more
Friday fold: two samples from Tennessee Tech
I spent some time in east central Tennessee last week, visiting the Earth Sciences department at Tennesee Technical University in their lovely newly-remodeled home on the main campus quad. In a hallway display case, they had many beautiful specimens on display to educate and inspire. Here are two lovely examples of folding. Terrific rocks to … Read more
The Overstory, by Richard Powers
This is an interesting novel. The book came highly recommended to me from two friends who have literary and environmental sensibilities that I respect, and it won the Pulitzer Prize for fiction this year, which is an accolade worth noting – a validation of its quality. It is a story about trees, and about “radical” … Read more
Friday fold: Rist Canyon cobble
From a creek bed in northern Colorado, the Friday fold distorts foliation in early Proterozoic quartzofeldspathic gneiss, peppered with small almandine garnets.
Friday fold: Newfoundland beach cobble
This Friday’s fold is found in a metasedimentary beach cobble I found last summer in southeastern Newfoundland: A lovely little “pocket fold,” it came home with me and is among the handful of “deskcrops” I keep in my home office. Happy Friday and happy November!
Friday fold: Identity of a BIF
The Friday fold is a slab of banded iron formation now dwelling in the University of Washington’s Department of Earth & Space Sciences. But where did it come from? India? Brazil? Perhaps you can help identify its provenance.
Friday folds from the Foreknobs Formation
TGIF! That’s my seven year old field assistant showing off the shape of a syncline in shale, siltstone, and fine sandstone of the Foreknobs Formation, a Devonian nearshore package of clastic sediment in the Valley & Ridge Province of eastern West Virginia. Want to see something freaky for Halloween? Photoshop can make it happen: Ewwww. … Read more
Friday fold: Watern Cove
A moderate mesoscale monocline at Watern Cove, Newfoundland, shows off multicellular animal fossils of the Ediacaran Mistaken Point Formation.
Book report
I’m way behind in writing about writing, but I’ve read a decent number of books (or listened to them) over the past few months. I apologize to each of these authors for lumping all these reviews into a single blog post, but this has collectively been on the back burner for months, and I’ve decided … Read more
Friday fold: Angel Island “IV”
Hey, let’s go back to Angel Island for today’s Friday fold. We’ve been there once, twice, thrice previously. The rocks in question are metaconglomerates that Jess Ball and I found at first only as float on the beach at Camp Reynolds, like these two examples: …Look at those beautiful elongated pebbles, transected by wee white … Read more
Friday folds: O’Shaughnessy Boulevard, Glen Canyon Park, San Francisco
The western edge of O’Shaughnessy Boulevard, near Glen Canyon Park in San Francisco shows beautiful examples of crumpled cherts. Here are a few dozen photos of these glorious outcrops, and instructions on how to visit.
Friday fold: crinkled schist from Italy
AGU’s Chief Digital Officer Jay Brodsky offers up a fresh European fold for you today — and this one is on rather a smaller scale than Jay’s last Friday fold contribution… Click through for a bigger version. These are lovely crinkly folds in highly foliated rocks. I love boxy little crenulations like these. Jay tells … Read more
Friday fold: Gonzen, Switzerland
Science writer Gabe Popkin shared two fold photos with me this week – both from near Sargans, Switzerland, adjacent to the Rhine River Valley and the border with Lichtenstein. The photos shows the mountain called Gonzen. There, Jurassic limestones crop out in a very wavy pattern: I don’t know the geology of this area in … Read more
An unconformity at Bacon Cove, Newfoundland
At Bacon Cove in eastern Newfoundland, there is a nice example of an angular unconformity between Ediacaran and Cambrian sedimentary rocks.
Friday fold: Calafia State Beach
The Friday fold is a guest contribution to “Mountain Beltway” from the manager of the AGU Blogosphere, Larry O’Hanlon. It shows apparent crumpling of a few sedimentary layers at the toe of a soft sediment slump at Calafia State Beach in southern California.