Monday macrobug: Praying mantis
Photographed this one before the leaves changed – a big gravid female. Look at the size of that swollen abdomen – much like my wife was on that same day!
Callan Bentley
Animated GIF of the Walker Top Granite
Here’s one of the cool rocks I saw on my pre-GSA-Charlotte field trip to the Neoacadian Inner Piedmont field trip: the protomylonitic Walker Top Granite (~366 Ma crystallization), which was deformed as the terrane it was intruded into got shoved up and to the west (and perhaps the southwest!). Here’s an animated GIF I made … Read more
Friday fold: dinner plate
The Friday fold appears on a flat slab along Maryland’s Billy Goat Trail.
A few folds from Betty’s Bay
Here are a few folds in the quartzites of the Cape Fold Belt, exposed on the mountainsides of the Harold Porter Botanical Gardens in Betty’s Bay, South Africa. Hillside #1: Zooming in closer: Annotated (bedding traced out): Hillside #2: Zooming in on summit region: Annotated (bedding traced out): Zooming in on the central portion of … Read more
Passage Creek the morning after Sandy
The storm treated us well last night. We got some rain and some consistently moderate wind, but nothing insane. When I got up this morning, I checked the stream gauge online, and saw that Passage Creek was up significantly, and perhaps over the little low-water bridge that connects our house to the outside world. So … Read more
Geology and wine in northern Virginia, part II: the Valley & Ridge
Callan attends the Geological Society of Washington’s fall field trip, examining the relationship between grape-growing and the underlying geology of two provinces in northern Virginia: the Blue Ridge and the Valley & Ridge. With GSW compatriots, Callan visited Hume Vineyards in the central Blue Ridge province and North Mountain Vineyard and Winery in the Shenandoah Valley. This is part II of the field trip report.
Hurricane Sandy in the Fort Valley
Up here on the northwest flank of Massanutten Mountain, Lily and I prepared for Hurricane Sandy in several ways. We bought a generator this week (actually, we ordered it last week before Sandy was a twinkle in the atmosphere’s eye, but it was delivered this week), we stocked up on food (pizza with fresh veggies … Read more
Monday macrobug: parsleyworm
Look what I found while out weed-whacking in the yard: (gloved fingers for scale) That’s the larva of the black swallowtail butterfly. This good-looking caterpillar is colloquially known as a “parsleyworm.” In these last two shots, check it out without and with the osmeteria (fleshy “horns” behind the head) everted in defense: The osmeteria get … Read more
Geology and wine in northern Virginia, part I: the Blue Ridge
Callan attends the Geological Society of Washington’s fall field trip, examining the relationship between grape-growing and the underlying geology of two provinces in northern Virginia: the Blue Ridge and the Valley & Ridge. With GSW compatriots, Callan visits Hume Vineyards in the Blue Ridge basement complex and North Mountain Winery in the Shenandoah Valley. This is part I.
Salt crystals in a tidal pool, Hermanus
Last winter, around 10 months ago, Lily and I were walking along the shore of Hermanus, South Africa, when I saw a little closed-drainage pool in the sandstone, harboring a briny distillation of the South Atlantic Ocean. Neat salt “rim” on the edge of the pool… Also note the ~cubic crystals at the bottom of … Read more
Friday fold: South African gneiss
Another Friday, another fold. …By another Bentley!
Monday macrobug: long beetle
This one popped up as I was splitting wood the other day. Here’s a very long beetle on fresh oak: As near I can figure, this fellow might be in the genus Calleida. I couldn’t find a perfect match, though.
Friday fold: Pofadder shear zone mylonites in 3D
Christie Rowe sent me these two images. They were taken by Ben Melosh and Louis Smit. The folded layers are mylonites of the Pofadder Shear Zone in South Africa. I love it when folds are expressed not only in profile, but also in three dimensions. Nothing in life could possibly be better. We’ve featured the … Read more
Convection in a dirty dish
Saw this in a greasy / soapy baking pan in my kitchen sink the other day: Do you see those lobe-shaped light areas, separated by dark septae? I think that’s the semi-gelled signature of gravitational instability, perhaps thermally driven. I’m speaking of convection: upwelling in the round light areas, and sinking of denser material in … Read more
Midnight Rising, by Tony Horwitz
A couple of weeks ago, I was killing time down in Front Royal, and I spent a pleasant hour in the Royal Oak Bookshop. I saw a used paperback copy of Tony Horwitz’s classic Confederates in the Attic there, and bought it, thinking I could give it away to a friend or visitor who didn’t … Read more
Monday macrobug: Grass spiders with hatchlings
We’ve got plenty of spiders out here in the Fort Valley. Here’s a look at one common species: a sweet momma grass spider striding along, carrying dozens of infant spiderlings on her abdomen: How many children can you count? A week or so later, I saw another one, with a similar load:
Friday fold: a dome in plane view
The Friday fold is a structural dome in Wyoming, as seen out an airplane window.
Wo(G)E #357
Callan hosts the 357th installment of the popular satellite imagery / geologic search game “Where on (Google) Earth?”
Dinosaur eggs from Devil’s Coulee, on display at the Royal Tyrrell Museum, Drumheller
Each one is the size (and shape) of a nice sourdough boule – Because they were in a glass case, I couldn’t get a good sense of scale in the same focal plane.