Month: October 2021
Ghostly Geology
Halloween is here! This is my favorite part of fall: costumes, spooky stuff, decorating in black not only allowed but encouraged…. This is the holiday I was born for.
And I have some geology made for the holiday! This year, the theme is ghosts, and we’re going to visit some very ghostly geology and paleontology indeed.
1. Ghost Shrimp Haunts Ichnologist
This is a different kind of ghost shrimp than the ones under discussion, but it is metal enough for Halloween, so we’re rolling with it. Credit:
Freddie Alequin (CC BY-SA 2.0)
Paleontology isn’t just about bones and preserved bodies: a branch of it, ichnology*, also looks at the things those bodies left behind, like fossilized trails, tracks, nests, burrows, borings, excavations, and even the divots left by pee. In this post, my favorite ichnologist, Tony Martin, talks about a very unusual trace he found that would be even more exciting to find in the fossil record.
Life Traces of the Georgia Coast: Ghost Shrimp Whisperer
Geologists love ghost shrimp, too, because of how their burrows are so numerous, fossilize easily, and are sensitive shoreline indicators. I wrote about this before with regard to how geologists in the 1960s were able to map ancient barrier islands of the Georgia coastal plain by looking for trace fossils of these burrows. Since then, geologists and paleontologists have identified and applied these sorts of trace fossils worldwide, and in rocks from the Permian Period to the Pleistocene Epoch.
I could prattle on about ghost shrimp and their ichnological incredibleness for the rest of the year, but will spare you of that, gentle reader, and instead will get to the point of this post. Just when I thought I’d learned nearly everything I needed to know about ghost-shrimp ichnology, one shrimp decided I needed to have my eyes opened to some traces I had never seen them make before just a few months ago.
*Not to be confused with ichthyology, which has to do with fishies. It’ll help to remember that ikhnos means “track” or “trace” in Greek, while ikhthus means “fish.”
2. Ghosts of Minerals Past (more…)
Why the Canary Islands are Like This
This post first appeared on Patreon. To get early access, plus exclusive extras, please visit my Patreon page.
The current eruption on La Palma in the Canary Islands is now over a month old. Already the island’s largest in a hundred years, it’s giving no signs of stopping just yet. Volcano lovers have thrilled to its spectacular Strombolian explosions. Residents have endured disruption, displacement, and loss of homes and livelihoods. Dogs trapped by lava flows had to be fed by drone before they were taken to safety in a daring and mysterious rescue. Living with a live volcano is far from easy and seldom safe.
Plenty of news agencies, vloggers, and blogs are keeping us up to date on the progress of the current eruption. I’m going to take us deep into the past, on a journey into the island’s origins and evolution. We’re going to see the slow, steady pas de deux between a mantle plume and the plate above it. We’ll watch underwater volcanoes go subaerial, building new land, and see catastrophic collapses tear their confections down. We’ll learn the life stages of a Canary Island, and by the end, we’ll know the broad outlines of La Palma’s destiny.
In the end, we’ll see that this current eruption is as much an act of creation as it is destruction.
Mirador de La Tarta, Tenerife. Yes, it’s literally called a cake! The white layer is pumice, the black layers are basaltic scoria, and the reddish-brown layers are oxidized basaltic tephra. Credit: H. Zell (CC BY-SA 3.0)
