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.
west virginia
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.
Slump palimpsest, Corridor H
There’s a section of my favorite road, the lovely nowhere-to-nowhere Corridor H, that seems to be having some issues with slumping. I noted this in November of 2015, and I return to the topic today. Here’s a look at the slope, with old drainage “French drains” installed, and a fresh scarp transecting it just the … Read more
Ripples in Foreknobs
The Foreknobs Formation is a Devonian unit in the Valley & Ridge province of the Mid-Atlantic Region. It was deposited in relatively shallow near-shore conditions during the Acadian Orogeny. On a field trip to Corridor H, a new highway transecting the West Virginian Valley & Ridge province on Monday, I stopped to document a couple … Read more
Friday (coal)d
Often I feature a fold photo here on Friday, but today I give you a folded coal, so therefore a “coald” – this is from the Pennsylvanian Conemaugh Formation on the Alleghany Plateau in West Virginia, near Bismarck. Photo by Sebastian Andres Kaempfe Droguett.
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.
Silent samples, holey samples
Two very different samples tell stories that are full of holes. What’s going on with this weathered sandstone? What’s going on with this fossil scallop shell?
3D models to spin and twist
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:
Another trio of 3D models
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:
3D virtual sample of gastropod-rich Reynolds Limestone
Check this out: It’s a sample of the Reynolds Limestone, a member of the Mississippian-aged Mauch Chunk Formation, chock full of gastropod fossils. The image here is a 3D model made with Agisoft PhotoScan, a 3D model rendering program. The only input was a series of ~32 photos taken of the sample at various angles … Read more