You are browsing the archive for 2017 April.
28 April 2017
Happy Friday! Here are two more folds in gneisses of the Lewisian, in the North West Highlands of Scotland, near Tarbet. Enjoy!
27 April 2017
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!
My latest book review is of a cutting-edge new novel that describes our current political dystopia in excruciating detail… Just kidding! Seriously: I was spurred to re-read Orwell”s 1984 after last November’s election, and the counterfactual customs of our new commander in chief. ‘Alternative facts’ have many precedents in history, but perhaps …
26 April 2017
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!
25 April 2017
I haven’t yet seen the blockbuster movie Hidden Figures, but I’ve heard great things about it. This post is about the book it’s based on, also called Hidden Figures, by Margot Lee Shetterly. It chronicles the work of numerous African-American women at NASA and its predecessor organization, NACA, through the middle of the last century. The book is a robust documentation of these women’s childhoods, educations, motivations, and lives. It …
24 April 2017
I marched on Saturday. In spite of the congested conditions in both the local atmosphere and my sinuses, I felt compelled to add my voice and presence to the March for Science, an event that was probably the first of its kind since the Enlightenment, aiming to push back against anti-science attitudes from the current occupant of the White House and his contemporaries on Capitol Hill. I tried to keep …
21 April 2017
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.
17 April 2017
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.
15 April 2017
My son and I hiked Compton Peak in Shenandoah National Park this morning, and saw these two lovely examples of xenoliths. The example above is small, but it shows clearly the difference between the coarse, felsic basement rock (Mesoproterozoic granitoid, comprising the xenolith) and the surrounding fine-grained dark green metabasalt of the Catoctin Formation (Neoproterozoic). Here’s another, bigger example: These two Blue Ridge examples both illustrate the principle of relative …
12 April 2017
Check this out: That’s a beautiful example of weathering in a dolerite dike on Arran. The igneous rock was broken along two more or less perpendicular joint sets, and then fluid flow along those fractures helped “rot” the adjacent rock through oxidation and hydrolysis. The resulting brownish weathering rind grows at the expense of the unweathered black rock. Because there is more surface area at the corners of the rock …