Callan documents a geological stroll along the coast of Esterillos Oeste, in central southern Costa Rica, investigating the sequence of sediment in the Punta Judas Formation (Mid-Miocene) exposed there. Fossils, sedimentary structure, diagenetic features, structural deformation, and modern weathering all make prominent appearances.
Here’s a cool little book about the paleobiology, ecology, and behavior of cephalopods: Squid Empire. The author, Danna Staaf, has a PhD in marine biology and –more importantly– a lifelong fascination with squid, octopuses, cuttlefish, and nautiloids. This work is a history of the cephalopod clade – going back into deep time, before the Cambrian … Read more
Mark Kurlansky might be the king of the micro-history. His books Salt and Cod were both excellent examinations of history in the context of those minerals and fishes. So when I saw The Big Oyster on the audio-book shelf at my public library, I checked it out, knowing roughly what I would get – a … Read more
The Cretaceous-Paleogene limestone called Scaglia Rossa was used to construct a basilica in tribute to St. Francis. Let’s head to Assisi and take a look.
I took a trip last week to Kentucky. My colleague Kent Ratajeski from the University of Kentucky took me out on a nice all-day field trip to examine some of the local geology. I was particularly impressed with the large straight nautiloid fossils that abounded in the Ordovician-aged Lexington Limestone. Here are a series of … Read more
The Octopus, the Sea, and the Deep Origins of Consciousness is the subtitle of this fascinating, extremely approachable book. Paraphrasing Thomas Nagle, it asks “What is it like to be an octopus?” The author is a philosopher by training, but he does a fantastic job as a science writer, too. Anecdotes about encounters with cephalopods … Read more
Don’t you hate it when plate tectonics ruins a perfectly good fossil? This is a sketch of a belemnite from the Swiss Alps: The thing has been broken into segments, with calcite filling the gaps between the segments. What a bummer! Now we’re going to have a much harder time reconstructing the life habits of … Read more
Two very different samples tell stories that are full of holes. What’s going on with this weathered sandstone? What’s going on with this fossil scallop shell?
One of my favorite places in Northern Ireland is the east side of the peninsula that hosts the tourist town of Portrush. There, two early schools of geological thought engaged in a battle. The opposing sides were: the Neptunists, who thought all stratified rocks, and in particular basalt, must form from precipitation from the sea, … Read more
Rathlin Island lies north of mainland Northern Ireland, a few miles offshore. I spent three lovely days there this past summer, investigating the geology and appreciating the wildlife (puffins and other sea birds, and seals). The geology is pretty straightforward: Paleogene basalt overlying Cretaceous “chalk” (really not so chalky here – technically, it’s the Ulster … Read more
My student Robin has been working (on and off) for more than a year to figure out the best way to make GigaPan-scale imagery using the new desktop scanning electron microscope that our academic division acquired. There are several technical challenges to be overcome, each different, and some with ‘solutions’ that cause other problems. Dealing … Read more
Check this out: It’s a sample of the Reynolds Limestone, a member of the Mississippian-aged Mauch Chunk Formation, chock full of gastropod fossils. The image here is a 3D model made with Agisoft PhotoScan, a 3D model rendering program. The only input was a series of ~32 photos taken of the sample at various angles … Read more
Hampshire Formation outcrops on Corridor H, West Virginia: link (Marissa Dudek) link (Callan Bentley) Faults in the Tonoloway Formation, Corridor H, West Virginia: link (Marissa Dudek) Conococheague Formation, showing stromatolites and cross-bedding: link (Callan Bentley) link (Jeffrey Rollins) Tiny folds and faults, from a sample I collected somewhere, sometime… oh well, it’s cool regardless: link … Read more
Two new GIGAmacro images of fossil scallops from Virginia’s Coastal Plain – Chesapecten nefrens: link Chesapecten jeffersonius: link My vision is to get the opposite side of each of these samples as well as a half-dozen other species in this genus, perhaps even multiple individual specimens of each species, to allow students to do a … Read more
Today, a few more photos from the field trip last month to Corridor H, the fine new superhighway with so little traffic out in eastern West Virginia. Our antepenultimate stop of the day was at an outcrop we inferred should hold the Oriskany Sandstone, a Devonian quartz arenite that lies stratigraphically above the Helderberg Group … Read more
I went out last Tuesday to Corridor H, the exemplary new highway cutting through the Valley and Ridge province of eastern West Virginia. Joining me was former student Alan Pitts, a devotee of Corridor H from way back in the early days when we just called it “New Route 55.” The boondoggle highway is now … Read more
At the eroded gully known as Devil’s Coulee in Alberta, you can find armored mudballs, dinosaur fossils (including eggshell), and even marine clams at higher levels in the sequence. Check out these lovely beasts: They lived and died on the western shore of the Western Interior Seaway during the Cretaceous period of geologic time. My … Read more
My mother-in-law collected a cool oyster for me: She found it down in Ecuador; I think on the beach. She says it’s a fossil, but I haven’t been able to identify it at all, as either ancient or modern. Anyone know?
Callan and his family visit a Virginia winery that features tasty libations and chunky nautiloid fossils, both products of the same local geology…
Cretaceous clams from the final big transgression of the Western Interior Seaway, the “Bearpaw Sea”: We saw these last month at Devil’s Coulee in southern Alberta. They’re big!