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Chris Rowan @allochthonous.bsky.social · 7h

I suddenly feel better about my 240!

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Chris Rowan @allochthonous.bsky.social · 7h

I want to know how the distribution changes if you ask about their phone browser.

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Reposted by Chris Rowan

Kelly Hereid @kellyhereid.bsky.social · 11h

Sheesh - a tsunami big enough to push coral boulders 100s of m inland in the British Virgin Islands around the year 1400, likely sourced from an earthquake on the Puerto Rico Trench.

Kevin Anchukaitis @thirstygecko.bsky.social · 12h

This is cool - new paper from Hali Kilbourne et al. 'Dating a Medieval Tsunami With Uranium-Series Techniques on Caribbean Corals' agupubs.onlinelibrary.wiley.com/doi/10.1029/...

Dating a Medieval Tsunami With Uranium‐Series Techniques on Caribbean Corals

Uranium-series analyses provide dates for 15 annually banded coral skeletons on the low Caribbean island of Anegada A subset of the corals was likely washed ashore in a Puerto Rico Trench tsunami...

agupubs.onlinelibrary.wiley.com

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Chris Rowan @allochthonous.bsky.social · 3d

The total disrespect for their students is just mind-boggling.

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Chris Rowan @allochthonous.bsky.social · 5d

⚒️ #FridayFault

James 🏴󠁧󠁢󠁳󠁣󠁴󠁿🦖 @thattalljacobite.bsky.social · 5d

Made the pilgrimage to Knockan Crag for the first time

Here 1 billion year old Moine rock has been thrust up and out of the Earth during the collision of Scotland and England over 400 million years ago, forcing it to slide and sit atop younger 500 million year old Durness limestone!

Geology rocks!

A long black coloured cliff sits atop a green-brown grassy hill beneath a white cloudy sky

A photo of me in blue crouched and touching two rock layers - black on top and yellow on bottom

The Moine thrust - a large layer of dark black-grey rock sitting on top of a smaller layer of yellow limestone rock

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Chris Rowan @allochthonous.bsky.social · 7d

🧪⚒️ “the complex organic molecules Cassini detected…are not just a product of long exposure to space, but are readily available in Enceladus’s ocean.”

As ever - these observations show some intriguing chemistry is going on, but that isn’t necessarily life.

Cassini proves complex chemistry in Enceladus ocean

Scientists digging through data collected by the Cassini spacecraft have found new complex organic molecules spewing from Saturn’s moon Enceladus. This is a clear sign that complex chemical reactions ...

www.esa.int

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Chris Rowan @allochthonous.bsky.social · 13d

Apparently, they didn’t even respect him enough to put him on the movie poster?

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Chris Rowan @allochthonous.bsky.social · 14d

On the other hand, LLMs do provide a good in-Universe explanation for technobabble.

Lord Businessman II @lordbusinessman.bsky.social · 14d

Starting to think that the least realistic far-future bit of Star Trek that they uncritically trust the computer

Reposted by Chris Rowan

Lego Lost At Sea @legolostatsea.bsky.social · 15d

Not sea glass but fragments of plastic car tail lights, indicators and brake lights, probably washed into storm drains after heavy rain, eventually making their way to the sea. #oceanplastic

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Reposted by Chris Rowan

Sarah McAnulty, Ph.D. @sarahmackattack.bsky.social · 19d

I wanted to get a video of this ghost crab but every time I got close to their hole they scuttled back in, so I tried getting clever with it. I made a little sandcastle and shoved my phone into it, hit record, and walked away. Crab was VERY suspicious of this addition to their environment.

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Reposted by Chris Rowan

Mike Tice @ticeonmars.bsky.social · 23d

I've been asked a few times over the last few days what I think the chances are that the "leopard spots and poppy seeds" on Mars will turn out to be actual evidence of life. People are naturally skeptical given the history of possible signs of life on other planets. Strap in: long thread ahead...

Image collected by WATSON on the Perseverance rover of "Cheyava Falls," a rock on Mars containing potential biosignatures

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Chris Rowan @allochthonous.bsky.social · 23d

I also strongly feel the urge to say ‘taenite’ in a Scottish accent.

#MinCup25

a man with gray hair is sitting in a chair and saying `` och ... i 'm scottish . ''

Alt: a man with gray hair and dressed in post-regeneration chic saying dramatically “och ... I’m Scottish.”

media.tenor.com

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Chris Rowan @allochthonous.bsky.social · 23d

Taenite is the material of protoplanetary cores - from bodies in the early days of the solar system that got big enough to differentiate, then blown apart by impacts. It’s a window into the inaccessible core of our own planet. Sorry clays, but taenite has my vote.

#MinCup25

Mineral Cup #MinCup25 @mineralcup.bsky.social · 24d

#MinCup25 Round 1 Match 15 - It's a mineral found mostly in the farthest reaches of space vs one so common an exhaustive list of localities is nigh impossible as alloy #taenite faces off against clay #nontronite.

Vote: www.mineralcup.org/2025/vote/r1...
Results: www.mineralcup.org/2025/results...

Vote in Round 1 Match 15 — Mineral Cup

Click here to vote in Taenite vs Nontronite Photo credits: Harold Moritz and Joan Garcia Santiago

www.mineralcup.org

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Chris Rowan @allochthonous.bsky.social · 24d

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Chris Rowan @allochthonous.bsky.social · 24d

They are interpreted as forming during one of the Neoproterozoic 'Snowball Earth' glaciations, "associated with the penetration of long-lived & extreme permafrost deep into subaerially exposed bedrock"

“Formed by cold deep & prolonged enough to suppress the geotherm” is literally extremely cool!

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Chris Rowan @allochthonous.bsky.social · 24d

But I think the coolest example I've found is ikaite pseudomorphs within metamorphosed Dalradian rocks in Scotland, where they appear to have grown *after* an episode of burial and metamorphism that generated a slatey cleavage.

pubs.geoscienceworld.org/gsl/jgs/arti...

#MinCup25

Series of images from a scientific paper, with the caption: Kerrera Slates. A: Bed of metadolostone with aligned ikaite pseudomorphs plunging (lower arrow) in the plane of the cleavage towards the NE, crenulation lineation in the slates is marked by upper arrow (Coin is 2 cm diameter); B: Aligned ikaite pseudomorphs in calcareous slate steeply plunging (arrow) to the NE. Pseudomorph size decreases towards lower part of exposure (Hand lens is 5 cm long); C: Aligned ikaite pseudomorphs in calcareous slates, arrow shows alignment of elongate grains (Hand lens for scale); D and E: Large elongate ikaite pseudomorphs with pyramidal terminations from the Easdale Slates.

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Chris Rowan @allochthonous.bsky.social · 24d

Ikaite pseudomorphs found in the rock record are usually referred to as 'glendonite', and because ikaite is associated with sediments deposited in cold bottom waters, glendonite can be used as a paleoclimatic indicator.

Figure from supplementary information of www.science.org/doi/10.1126/...

Heat map showing Phanerozoic distribution of glendonite (pseudomorph after the hydrated carbonate ikaite) over time (horizontal axis, from about 450 million years ago on the left to the present on the right, divided into what looks like 1 million year bins) and space (vertical axis, from 0 degrees absolute latitude on the bottom to 90 degrees at the top, 5 degree bins). Where glendonite has been identified within a particular age/latitude bin, it is shaded a light pink for a low number of recorded occurrences, green for a moderate number of recorded occurrences, and blue for a high number of recorded occurrences. The distribution of glendonite occurrences is shown to be very non-uniform over geological time, with low to intermediate counts between 40 degrees and 75 degrees latitude in the past 50 million years; largely moderate to high counts between 60 and 90 degrees latitude from about 180 to 100 million years ago; and low to intermediate counts between about 45 and 85 degrees latitude from about 300 to 240 million years ago.

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Chris Rowan @allochthonous.bsky.social · 24d

Ikaite, on the other hand, is a geological ghost! Although it is metastable and does not persist in the geological record, its crystal form persists as pseudomorphs, where the replacement mineral (usually calcite) retains the shape of the mineral it is replacing.

#MinCup25

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Chris Rowan @allochthonous.bsky.social · 24d

Cuprosklodowskite looks like the anthropomorphic manifestation of a deadly substance, is appropriately radioactive and (also appropriately, if rather morbidly) named after Marie Curie, and is a dead ringer for kryptonite?

No, thank you!

#MinCup25

Mineral Cup #MinCup25 @mineralcup.bsky.social · 25d

#MinCup25 Round 1 Match 14: It's radioactive #cuprosklodowskite vs ephemeral #ikaite for today's match.

Vote: www.mineralcup.org/2025/vote/r1...
Results: www.mineralcup.org/2025/results...

Vote in Round 1 Match 14 — Mineral Cup

Click here to vote in Cuprosklodowskite vs Ikaite Photo credits: Harold Moritz and Uli Kunz, SUBMARIS 2024 from Aðalsteinsdóttir et al

www.mineralcup.org

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Chris Rowan @allochthonous.bsky.social · 25d

Correct, if I’m reading correctly - it’s that they are not associated with galaxies.

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Chris Rowan @allochthonous.bsky.social · 25d

So #TIL that at least some topaz forms by vapour deposition in the gas bubbles/cavities of cooling rhyolite lava flows. 😮

Others form in pegmatites, for which my appreciation is already on record 🤩

Two ultra-cool formation mechanisms means #Topaz gets my vote.

#MinCup25

Mineral Cup #MinCup25 @mineralcup.bsky.social · 26d

#MinCup25 Round 1 Match 13: It's a battle of high-pressure colourful beauties of #topaz vs #kyanite. Which can stand the heat of round 1?

Vote: www.mineralcup.org/2025/vote/r1m13
Results: www.mineralcup.org/2025/results/r1m13

Vote in Round 1 Match 13 — Mineral Cup

Click here to vote in Topaz vs Kyanite Photo credit: Smithsonian Institution

www.mineralcup.org

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Chris Rowan @allochthonous.bsky.social · 25d

🧪 Cool subtext to this cool story on the “little red dots’ - possibly primordial black holes! - dotting the early Universe is that the hopes for the James Webb telescope have been realised. It is pulling back the curtain on puzzling and unexpected things that will help us understand how we got here.

A Single, ‘Naked’ Black Hole Rewrites the History of the Universe | Quanta Magazine

The James Webb Space Telescope has found a lonely black hole in the early universe that’s as heavy as 50 million suns. A major discovery, the object confounds theories of the young cosmos.

www.quantamagazine.org

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Chris Rowan @allochthonous.bsky.social · 25d

Today in “the myriad ways your children make you feel old”: when I was the age my youngest is now, the year 1999 seemed impossibly far into the future.

Now, when they tell me stories, ‘in 1999’ is a shorthand for ‘a long time ago’.

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Chris Rowan @allochthonous.bsky.social · 26d

Link to article in quoted excerpt:

techcrunch.com/2024/12/18/e...

Exclusive: Google's Gemini is forcing contractors to rate AI responses outside their expertise

Internal guidelines passed down from Google led to concerns that the AI model could be prone to inaccurate outputs on topics like healthcare.

techcrunch.com

Chris Rowan @allochthonous.bsky.social · 26d

👀 pushing people to rate answers on subjects they have limited knowledge of seems almost designed to push the models towards truthiness.

https://www.theguardian.com/technology/2025/sep/11/google-gemini-ai-training-humans

Text Shot: In December, Google sent an internal guideline to its contractors working on Gemini that they were no longer allowed to “skip” prompts for lack of domain expertise, including on healthcare topics, which they were allowed to do previously, according to a TechCrunch report. Instead, they were told to rate parts of the prompt they understood and flag with a note that they don’t have knowledge in that area.

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