Friday fold: Big kink fold in Grinnell Formation
It’s Friday! How about we celebrate with a beautiful kink fold from a gorgeous national park?
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Friday fold: chevrons in the Scaglia Rossa, Apennines
The Friday fold visits the Apennine Range of central Italy.
Friday fold: marble in a thermopolium at Herculaneum
It’s Friday. Let’s find a historic sort of Friday fold in the ruins of Herculaneum, Naples, Italy.
Loading sags in homogeneous lithologies?
Can soft sediment deformation “loading structures” (ball & pillow) occur when the two strata are identical in composition? Grok on these field photos and chime in with your best hypothesis.
Friday fold: Macigno turbidites II
It’s Friday. We return to Italy’s Macigno Formation for a fold, courtesy of blog reader Samuele Papeschi.
Chert-slab conglomerate from the Fig Tree Group, Barberton
Deep in the Archean, things suddenly got violent in the deep water of the Mapepe Formation’s oceanic setting. What was a quiet precipitation of chert suddenly was torn apart and tumbled downslope. Was an earthquake to blame? A bolide impact? This is the result.
Silurian tidal flat carbonates of the Tonoloway Formation
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.
Friday fold: sea monster in stone
It’s Friday, the end of the workweek, but also the beginning of the celebration of folded rocks. Examine a particularly sinuous example from the buckled Cambrian limestones of Canada’s Kootenay National Park.
Storm beaches have I loved
The answer to yesterday’s geo-puzzle is revealed to be a storm deposit of boulders, 20 m above sea level!
Leafing out to bring down CO2
It’s getting green outside – what’s it mean for the planet? Find out in this blog post contemplating the relationship between spring leaves and atmospheric CO2.
Accretionary lapilli from Archean volcanic eruptions
Volcanic “hailstones” called accretionary lapilli rained down on South Africa 3 billion years ago, and have survived to be seen in the present day, along the R40 road through Barberton Mountain Land, near the Bulembu border crossing into Swaziland.
Friday fold: Two more from the Lewisian gneiss of Scotland
Happy Friday! Here are two more folds in gneisses of the Lewisian, in the North West Highlands of Scotland, near Tarbet. Enjoy!
Identifying logical fallacies and scientific misdirection in a CO2 video
A quick exercise in deconstructing the argument of a “elevated CO2 is good” video on YouTube by identifying its logical fallacies. Pull up a chair, grab a bowl of popcorn, and join us in the critique!
Pseudocraters at Lake Mývatn, Iceland
Near the southern end of Lake Mývatn, astride the Mid-Atlantic Rift in northern Iceland, lies a field of “pseudocraters” that result from steam explosions beneath a fresh lava flow. Put on your head-net and join us to check it out!
Liesegang rings in a natural sandstone “tile”
An easter egg on a piece of toast? No, it’s a nice example of Liesegang rings in a slab of sandstone. Explore more in this blog post.
Friday fold: paper demo
The Friday fold is a sheet of paper. Yes, really!
Stac Fada
The evidence for a meteorite impact origin for the Stoer Group’s Stac Fada member seems to stack up. Engage in a virtual field investigation on Mountain Beltway.
P-sol in a conglomerate countertop slab
A hardware parking lot in rural Virginia showcases an elegant slab of pressure-solution induced compaction of a conglomerate.
Cleaved, boudinaged, folded Edinburg Formation southwest of Lexington
Explore a dozen photos highlighting the structural geology of an outcrop of limestone and shale near Lexington, Virginia. Cleavage refraction, overturned beds, boudinage, folds, and even a small fossil – we’ve got something for everyone. Bring the whole family!
Pocketknife for scale
Geologists often use pocketknives as a sense of scale. Here’s why that may not be such a good idea!