Just finished a geologically focused book that the readers of this blog might be interested in. It is a history of work on delineating the early part of the Phanerozoic timescale in Wales and Scotland. The majority of the book is about Adam Sedgewick and Roderick Murchison and their close collaboration and increasing divergence and … Read more
I spent yesterday on Corridor H in eastern West Virginia’s Valley & Ridge province. The rocks here are a mid- to upper-Paleozoic set of strata that record the switch from post-Taconian passive margin sedimentation into Acadian clastic deposition, and then everything is deformed by Alleghanian folding and thrusting. I found myself taking photographs of the … Read more
Callan shares a few outcrops from coastal Maine, part of the Avalonia terrane that accreted to ancestral North America during the Acadian Orogeny. They are volcaniclastic rocks, coarse and fine, and showing both overprinting kink bands and cross-cutting basaltic dikes.
A quick “Friday fold” that is expressed in three dimensions – “stairstep” style folds deforming a bed of Tonoloway Formation dolostone…
Eric Fulmer (who pitched in with last week’s Friday fold) returns this week with another treasure. He writes, I was in Hopeville, WV a couple of years ago. The entire area between Cabins and Hopeville is a real joy (geologically and recreationally) as some of the most resistant rocks of the Mid-Atlantic Appalachians are folded … Read more
Reader Eric Fulmer has contributed a fold as a balm for the end of another week of COVID-19 self-quarantine. Check it out: Eric writes, I was in Hopeville, WV a couple of years ago. The entire area between Cabins and Hopeville is a real joy (geologically and recreationally) as some of the most resistant rocks … Read more
On a family hike, Callan’s son finds some interesting smooth lines on a rock. What are they? What do they tell us? Tune in for a brief history of Appalachian geology.
For the Friday fold, Callan digs out images of Eagle Rock, Virginia, well aged in his digital archive for a decade!
Journey to the Silurian period in what is today the Valley & Ridge province of eastern West Virginia to see some exquisite sedimentary rocks that represent deposition in a very arid, very shallow setting.
Time for another virtual field trip on the Geologist’s Grand Tour of the United Kingdom: the most famous outcrop in the world. Today, we visit Siccar Point, Scotland. You’ve probably already seen photos of this place – they usually look something like this: To those who aren’t familiar, here’s what going on: There are two … Read more
Our series of virtual samples continues! This week, I’m 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 feature a lovely slab of limestone, chock full of fossil material, and showing … Read more
Over the weekend, my wife and I took a walk with our son at the Storybrook Trail, an accessible trail with a fine overlook to the east over the Page Valley. There, the Massanutten Sandstone shows a bunch of big beefy trace fossils at this site: both bedding-parallel (Arthophycus-like) and bedding-perpendicular (Skolithos-like) traces. Here’s Bax … Read more
More 3D models: digital facsimiles of real rock samples. Check them out and explore! Clinker from the Powder River Basin, Wyoming: Ripple marks from the Rose Hill Formation, West Virginia: Meta-komatiite from the Red Lake Greenstone Belt, northern Ontario, Canada:
Here are three more of my Photoscan-generated, Sketchfab-hosted 3D models of rock samples: Mud cracks in Tonoloway Formation tidal flat carbonates, Corridor H, West Virginia: Diorite from the eastern Sierra Nevada of California: Vein cross-cutting foliated & lineated gneiss, Blue Ridge basement complex, Virginia:
It’s been a week and a half since Mountain Beltway has seen any publishing action, given the overlapping timesucks of the AGU Fall Meeting and the end of the semester. But now I’m back in the Appalachian mountain belt, and my grades are all in, and I have time to think about indulgences like blogging … Read more
Route 33 in Pendleton County, West Virginia cuts across the lower Paleozoic stratigraphic section. I went there this past spring on a sedimentology and stratigraphy field trip with the GMU sed/strat class. The trip was orchestrated by professor Rick Diecchio. Here are some scenes from two of the stops – the upper Ordovician Juniata formation … Read more
I have a mystery for you today: These are samples of Tonoloway Formation carbonate (not sure if it’s limestone or dolostone in retrospect), with bedding more or less horizontal in these images, and a few petite stylolites running orthogonal to that. The top sample has a gentle fold 2/5ths of the way across. All of … Read more
An outcrop of Silurian-aged Rose Hill Formation in West Virginia reveals excellent examples of ripple marks and trace fossils.
Milepost 127.4 (High, 2001) on the C&O Canal: …Cool if you’re into history. …Cool if you’re into economic geology. …Cool if you’re into Friday folds! Reader Eric Fulmer sent me this photo (along w/ two others you’ll see in weeks to come). Thanks, Eric!
Three images, working our way in from outcrop setting to hand sample: link link link These fine red sandstones are the Silurian-aged Bloomsburg Formation, as it crops out in Fort Valley, Virginia. What would we see if we kept zooming in? …Stay tuned…