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7 December 2022
The coastal section at Esterillos Oeste, Costa Rica
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.
3 April 2019
Squid Empire: The Rise and Fall of the Cephalopods, by Danna Staaf
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 Explosion, dwelling on ancestral forms and luxuriating in the ammonites (now sadly extinct — or …
17 October 2018
The Big Oyster, by Mark Kurlansky
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 history anchored to that particular delicious mollusk. In this case, it’s a history of New …
18 April 2018
Visiting St. Francis’s lovely limestone
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.
9 April 2018
Orthocone nautiloids of the Lexington Limestone
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 photos I took of these orthocones, all on pavement exposures (horizontal bedding planes) with my …
15 February 2018
Other Minds, by Peter Godfrey-Smith
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 while diving are mixed with careful, deliberate, dejargonized descriptions of the scientific studies that have …
12 December 2016
Fossils as strain markers: the boudinaged belemnites of the Swiss Alps
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 the organism that left this fossil behind… It was a squid-like thing, with an internal …
8 December 2016
Silent samples, holey samples
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?
11 October 2016
A virtual field trip to Portrush, Northern Ireland
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, and the Plutonists, who thought some rocks, including basalt, formed through intrusion of molten rock …
3 October 2016
A virtual field trip to Rathlin Island, Northern Ireland
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 White Limestone). Here’s a suite of interactive imagery that you can use to explore Rathlin’s …
22 April 2016
A suite of plankton S.E.M. micro-GigaPans
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 with all that takes time and has caused a lot of frustration. (We have a …
17 February 2016
3D virtual sample of gastropod-rich Reynolds Limestone
Check this out: [sketchfab id=”2acb8b4130ad467791fa62c00d7a8b18″ start=”0″ spin=”” controls=”0″] 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 and orientations. Alan Pitts then posted it to his Sketchfab …
12 September 2015
New GigaPans from Team M.A.G.I.C.
Hampshire Formation outcrops on Corridor H, West Virginia: [gigapan id=”178008″] link (Marissa Dudek) [gigapan id=”177198″] link (Callan Bentley) Faults in the Tonoloway Formation, Corridor H, West Virginia: [gigapan id=”176602″] link (Marissa Dudek) Conococheague Formation, showing stromatolites and cross-bedding: [gigapan id=”177155″] link (Callan Bentley) [gigapan id=”177355″] link (Jeffrey Rollins) Tiny folds and faults, from a sample I collected somewhere, sometime… oh well, it’s cool regardless: [gigapan id=”178807″] link (Robin Rohrback) Fern …
14 April 2015
Compare and contrast: Two Chesapectens
Two new GIGAmacro images of fossil scallops from Virginia’s Coastal Plain – Chesapecten nefrens: [gigapan id=”170847″] link Chesapecten jeffersonius: [gigapan id=”171285″] 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 lab where they plot morphological changes over geologic time as an …
