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