Friday fold: bend in a vesicular lava flow, Etna

It’s the First Friday of Fall! Here’s a sort of fold to help you celebrate: a section through a ∧ shaped bend in a vesicular basalt flow from the eastern flanks of Mount Etna in Sicily. It’s due to volcanic lava flowing rather than ductile deformation of a pre-existing solid rock (our usual habit with … Read more

Friday folds: the Roman Forum

When in Rome, do Friday folds as the Romans do? Here are some images from my brief, sweltering visit to the Roman Forum(s) this past summer. The whole region is a jumblepile of ancient ruins in a thousand styles. Almost nothing is labeled. It looks like this: This particular building held up a bit better, … Read more

Flow-banded rhyolite from Vulcano, Italy

I collected only a single rock on my summer travels in France and Italy. (Those of you who know me will realize how extraordinary this low number is!) It’s a flow-banded rhyolite from Vulcano, in the Aeolian Islands north of Sicily a few weeks ago. It contains porphyritic vesicular basalt xenoliths. I featured a similar … Read more

The Seven Hills of Rome: A Geological Tour of the Eternal City, by Grant Heiken, Renato Funiciello, and Donatella de Rita

I’m preparing for some time in Italy this summer, and picked up a couple of books to bring me up to speed geologically. The first is a geological guide for Rome. It’s structured around the archetypal “seven hills” of Rome, but the story is simpler in many regards than some other seven-hilled European capitals I … Read more

Cushendun Conglomerate of the Cross Slieve Group, Northern Ireland

Want a geological irony? Here’s one! You’re looking at a rounded boulder of Cushendun Conglomerate, a Devonian “Old Red Sandstone” unit (Cross Slieve Group) exposed at Cushendun Caves, Northern Ireland, U.K. The irony lies in the repetition of history – a tumbling environment of high water energy, rounding cobbles and boulders and depositing them, in … Read more

Friday fold: 3D syncline in Macigno Formation

Alan Pitts is the source of today’s fold, a beautiful 3D model of a differentially-weathered sycline in the Late Oligocene to Early Miocene deep water Macigno Formation from western Tuscany, Italy. Here’s a photo: Now for the 3D model, hosted by Sketchfab; After it loads, use your mouse to grab this thing and finesse it … Read more

Five new GIGAmacro images

Here are a few new images I’ve been working on with my home-based Magnify2 imaging system from GIGAmacro. Strophomenid brachiopods from Mississippian Mauch Chunk Formation, West Virginia: Link Boninite from New Caledonia: Link Lepidodendron scale-tree bark from Poland: Link Potassium feldspar crystal, from a pegmatite: Link Catoctin Formation greenstone from a feeder dike east of … Read more