Friday fold: Refolded marble from Corsica
The Friday fold comes to us from Corsica via University of Washington structural geologist Darrel Cowan. It’s a marble that’s been folded *twice!*
marble
Friday fold: Connemara Marble, Ireland
Another guest Friday fold (keep ’em coming, folks!) – This time from Eric Pyle of James Madison University: This is a weathered outcrop of the Connemara Marble in western Ireland, about a meter wide. Thanks for sharing, Eric!
Building stones of the Acropolis (Athens, Greece)
As a follow-up to my post about the geology of the Acropolis klippe in Athens, Greece, and in the spirit of my post on the building stones of the Haghia Sophia in İstabul, Turkey, let’s turn our attention today to the various rocks that ancient Greeks used to construct the buildings of the Acropolis, such … Read more
In search of Santorini’s blueschist, part 1: into the Valley of the Shadow of Ash
While in Santorini, Greece, your humble geoblogger braves a warm afternoon to search the hillsides for evidence of subduction.
Friday fold: passively folded marble
It’s Friday! Here’s Baxter, last Friday, in Athens, Greece. He’s checking out some folds in the marble that’s everywhere in that city: This is a lovely example of passive folding, where all the rock layers being folded have about the same viscosity (low viscosity contrast between layers). No buckling, as a result… Enjoy the weekend, … Read more
Friday fold: Shuswap marble, British Columbia
Howard Allen, a blog reader from Canada, digitized a bunch of folds for us from his old Kodachrome slides. You’ll be seeing selections from these images over the weeks to come. Get psyched! There are some great folds in this batch. Here’s the first: Howard’s description: 3D folded marble, Shuswap Metamorphic Complex, north of Sicamous, … Read more
Four new GigaPans from an intriguing contact
Callan and his colleague Jay Kaufman (University of Maryland) go to extraordinary lengths to document an intriguing block of rock in northern Virginia’s Blue Ridge province. Great images and a lot of fun result – but what do these rocks tell us?
Kink fold in Castner Marble
One more structure from the Castner Marble. This one is clearly tectonically-induced: Top to the left! (East over west)
Castner Marble
The Castner Marble is an extraordinary Mesoproterozoic limestone (later re-crystallized and metamorphosed) that exhibits some primary structures (both explicit and ambiguous) and some secondary (tectonic) overprints. It’s exposed in the Franklin Mountains of west Texas.
Tavşanlı Zone field trip, part 7
Part 6 of the Tavşanlı Zone field trip had us looking at some blueschists and eclogites. Today we conclude the terrific field trip with a brief look at a couple more stops.
Tavşanlı Zone field trip, part 6
Part 5 of the Tavşanlı Zone field trip left us eating lunch amid some fine blueschists. Of course, nothing tops off a blueschist lunch like… more blueschist. So after our meal, we took another stroll through the countryside in search of more interesting subduction zone rocks… I’;ve got a bunch more photos for you today. … Read more
Friday fold: contorted Sivrihisar marble
Highly contorted laminations in a blueschist-grade marble, Sivrihisar massif, Turkey.