Cross-bedding in Archean komatiitic ash deposits
Cross-bedding isn’t just for modern sedimentary deposits; you can find it in truly ancient ash deposits too! Let’s head to South Africa and take a look.
Losing Ron and Declan
Last week, I lost two of my colleagues, Declan De Paor and Ron Schott. Both were involved in Google Earth for On-site & Distance Education (GEODE), the 5-year project I serve as PI on. Declan had battled various forms of cancer for many years, and most recently had developed several brain tumors. His passing was … Read more
Friday fold: a quartet from Marli Miller’s website
Marli Miller is a senior instructor at the University of Oregon. She is the author of Roadside Geology of Oregon and (with Darrel Cowan) Roadside Geology of Washington. She’s also a very talented geological photographer. She launched a website recently to showcase her work and make it available for instructors: Geology Pics. After chatting with … Read more
Friday fold: 3D model of intense folding
This is a block of rock I found in the rock garden at Northern Arizona University a few weeks ago: It’s intensely folded. Not sure what kind of rock it is, but it was quite dense.
Friday fold: Corsican blueschist sheath fold
The Friday fold takes us to the French Mediterranean island of Corsica. Are you ready to dip into the blueschist facies in search of sheath folds?
A Most Improbable Journey, by Walter Alvarez
As mentioned the week before last, Walter Alvarez has a new book out. I’ve read it. It’s good. It’s Alvarez’s take on what he calls “Big History” – the story that spans the cosmos, the Earth, life, and humanity. It’s pretty great for the reasons that Alvarez’s other books are excellent – his voice is … Read more
Last Stand, by Michael Punke
A reader of this blog recently recommended Michael Punke’s Last Stand. I thoroughly enjoyed his novel The Revenant, and so last week I started the audiobook version of the nonfictional Last Stand (2007). Last Stand is subtitled “George Bird Grinnell, the Battle to Save the Buffalo, and the Birth of the New West.” Prior to reading … Read more
2/3 pass rate on determining geopetal “up”
A visual challenge via Twitter to determine stratigraphic younging direction ends with equivocal results. So let’s use GIGAmacro imagery to school your sedimentological students on how three primary sedimentary structures look different right-side-up versus up-side-down.
Friday fold: Cape Liptrap
Sandra McLaren of the University of Melbourne is the source of today’s guest Friday Fold. Let’s join her on a journey with her students to Cape Liptrap (southeast of Melbourne in Victoria, Australia) on a lovely day: What a spectacular place. (We have featured folds from this site previously.) Happy Friday all!
Natural Bridge State Resort Park, Kentucky
A visit to a natural sandstone arch (or “bridge” as the locals call it) in eastern Kentucky yields unexpected bonuses, like fossil wood, Liesegang banding, and the honeycomb-like weathering pattern called “tafoni.”