GeoBits: Unearthly, Bizarre and Shiny Edition

Hello, and welcome to GeoBits, wherein I give a formal name to the occasional roundups of tasty geoscience news we do here. This inaugural edition has some truly incredible and inspiring stuff.

We begin with a seismic mystery on November 11th that had some scientists joking about sea monsters.

That day, seismographs all over the world registered a very low-frequency tremor, a strange grumble that lasted for around 30 minutes. One segment of the signal also featured several high-frequency blips, each separated by roughly a minute of time, a bit like a regular, ticking clock.

Stephen Hicks, a seismologist at the University of Southampton, highlighted the phenomenon in a November 12 tweet. “Something biggggg, yet strangely slow, sent seismic rumblings around the surface of much of the planet yesterday,” he wrote. Today, that succinct summary still holds, even as discussion of the event continues between geoscientists of all kinds over on Twitter.

To date, no one is quite sure what caused it. It wasn’t a tectonic earthquake, a landslide, nor a meteorite impact. Some experts baffled by the seismic enigma have not-so-seriously suggested that perhaps, finally, it’s sea monsters.

The truth may be even more exciting (unless you’re a cryptozoologist, in which case, you’ll be a tad disappointed):

The French Geological Survey (BRGM) is closely monitoring the recent shaking, and it suggests that a new center of volcanic activity may be developing off the coast. Mayotte was formed from volcanism, but its geologic beasts haven’t erupted in over 4,000 years. Instead, BRGM’s analysis suggests that this new activity may point to magmatic movement offshore—miles from the coast under thousands of feet of water.

[snip]

Since mid-July, GPS stations on the island have tracked it sliding more than 2.4 inches to the east and 1.2 inches to the south, according data from Institut National de L’information Géographique et Forestière. Using these measurements, Pierre Briole of the Ecole Normale Supérieure in Paris estimated that a magma body that measures about a third of a cubic mile is squishing its way through the subsurface near Mayotte.

This is where I start making “Eeeeeeeee!” sounds and running about in circles flapping my hands like a kid overcome by the coolest present they’ve ever seen. The entirety of that National Geographic article is a joy to read, and the idea we may be witnessing the birth of a new volcanic center makes the end of this year thrilling indeed!

Here’s a thrill for the dinosaur lovers: some very excellent footprints!

A trove well-preserved dinosaur footprints has been uncovered on a beach in southern England. Dating back to the Cretaceous Period, the prints still show traces of skin, scales, and claws.

Paleontologists from the University of Cambridge have uncovered 85 dinosaur footprints from at least seven different species on a beach in East Sussex near Hastings, England. It’s now considered “the most diverse and detailed collection of these trace fossils from the Cretaceous Period found in the UK to date,” according to a statement.

The prints range in size from around a three-quarters of an inch (2 cm) to nearly 24 inches (60 cm) across. The researchers, led by Anthony Shillito, a PhD student in Cambridge’s Department of Earth Sciences, were able to identify some of the dinosaurs responsible for the prints, including an Iguanodon, an Ankylosaurus, a species of stegosaurus, and some unidentified sauropods (long necked, four-legged herbivores). The level of detail in some of these prints is truly remarkable.

Good old England. She’s still got some magnificent paleontology to reveal. And to be able to see such clear detail that you can see the scales and claws on a dinosaur’s foot, tell how it traveled, and see who was around at the time, is an utterly fantastic thing. Those fossil footprints are glimpses into ordinary life over a hundred million years ago. There are volumes of stories in such things. Someday, someone too young to read this blog just yet will take a fresh look at this discovery, and reveal details we haven’t yet seen. I hope to still be writing on that day, and that you’ll be here to read about it.

In out-of-this-world news, the Mars InSight lander made a successful touchdown, and will soon be doing the kind of below-the-Martian-surface geology we could only dream of until now:

The InSight mission will attempt to improve this model with its suite of diverse instruments. A round, dome-shaped seismometer will sit on the surface and patiently wait for vibrations or, as they’re known on Mars, marsquakes. (A previous NASA mission, Viking, brought two seismometers to Mars, but only one deployed successfully, and scientists suspect that the sole seismic event the instrument managed to record may have been a product of powerful winds.)

Another instrument will burrow nearly 16 feet into the soil to measure the heat coming from the interior of the planet, which, like Earth, is still cooling from its fiery creation 4.5 billion years ago. A third instrument will focus on the lander itself, tracking its position as the planet wobbles during its orbit around the sun, which can reveal information about the size of the core.

Scientists hope that the InSight mission will help explain why Earth and Mars, forged from the same nebulous cloud billions of years ago, grew into such different worlds. “Our measurements will help us turn back the clock and understand what produced a verdant Earth but a desolate Mars,” Banerdt, who leads the mission, said recently.

This is going to take interplanetary geoscience to a whole new level. The discoveries that will emerge from this mission will refine and possibly revolutionize our understanding of Mars, the Universe, and everything.

I may be exaggerating, but I think only a bit.

Finally, let’s end with something very big and very shiny: the largest diamond in North American history.

It gets quite chilly in the northwest region of Canada but the diamond industry in the area is starting to burn red hot as a 552-carat yellow diamond was discovered in October.

The rough diamond was unearthed at the Diavik Diamond Mine, approximately 135 miles south of the Arctic Circle in Canada’s Northwest Territories, jointly owned by mining companies Rio Tinto and Dominion Diamond Mines, which made the announcement Friday.

It is the largest diamond discovery in North America, far surpassing the previous record held by the 187.7-carat “Diavik Foxfire,” which was recovered at the same mine in 2015.

One of these days, we’ll need to mosey up that way and investigate what geological happenings led to a diamond of that size ending up being pulled out of the crust. It’s sure to be a wild, weird story.

That’s it for this edition. See you next time my grab bag is full!



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