Friday fold: multilayer buckle folding demo

Check out this video I found online whilst uploading last week’s Friday fold: This video was produced and published on YouTube by Markus Beckers, Michael Ketterman, Dennis Laux and Janos Urai. It’s a nice demonstration of how multiple layers of material of different properties and different thicknesses can yield up different flavors of folds. In [...]

Lessons from a broken bottle

Whilst hiking at Dolly Sods over the weekend, I found this old artifact: Upper 10 is apparently a “Sprite”-esque lemon-lime soda, discontinued in America but still being marketed abroad. But that wasn’t what got me jazzed, of course. Look more closely… That is a lovely little conchoidal fracture, and it’s so exquisite because it preserves [...]

Pristine stratigraphy vs. bioturbated

Beautiful fiancée for scale.

What does Callan see here?

Tell me why I took this iPhone picture, and I’ll mail you a GEOLOGY ROCKS bumper sticker! Answer in the comments below…

Uniformitarian

Heat-stressed map of the Chesapeake Bay / Washington, DC region, as seen at Kenilworth Aquatic Gardens. Looks like mudcracks, eh? Similar stresses; similar strains.

Butter Buster animation

A million years ago, I posted about my inaugural attempt to use the Butter Buster to illustrate shear zone deformation to my structural geology students. Today, using the UnFREEz program to make an animated GIF (Thanks, Lockwood!), I give you the Butter Buster animation:

Sugarloaf

Sunday morning, NOVA adjunct geology instructor Chris Khourey and I went out to Sugarloaf Mountain, near Comus, Maryland, to poke around and assess the geology. Sugarloaf is so named because it’s “held up” by erosion-resistant quartzite. It’s often dubbed “the only mountain in the Piedmont,” which refers to the Piedmont physiographic province. Here’s a map, [...]

Snowy décollement

Earlier in the month, during the big snowstorms, my window got plastered with snow. This snow formed a vertical layer which then deformed under the influence of gravity. Looking at it through the glass, I was struck by how it could serve as a miniature analogue for the deformation typical of a mountain belt. Let’s [...]

Salamander shear

Whilst discussing how to quantify strain with my GMU structural geology students recently, I hit upon a cool analogy. In order for you to understand the analogy (assuming you’re not a structural geologist), I’ll have to review some background information first. Stick with it, and I promise you a salamander at the end. Structural geologists [...]

Normal fault in hedgetop snow stratum

Intersection of 16th Street and Columbia Road NW… … a wee bit underexposed, eh? Guess the high albedo blew out my iPhone camera. (glove for scale)