Thread by @SoilManDan

Hey folks, given all the drama over #HuntingAtlantis I thought I would clarify a few points about the scientific technology used in the show by @jessphoenix2018 . So I give you:

The ‘Science’ of #HuntingAtlantis Part 1: Science Machines and Make-Believe

That ray-gun that @jessphoenix2018 brings out sometimes is called a Portable X-Ray Fluorescence device, or a pXRF for short. The machine shoots x-rays at your chosen target, and reads the energy which comes back in order to determine what elements it’s looking at

This technology is heavily used by geologists and archaeologists alike (and definitely by geoarchaeologists like yours truly). It can help identify ancient paints and pigments, to analyse soils, and even to source some stone like obsidian. And it looks like a phaser!

But let’s talk about what it doesn’t do.

In episode 6 of “#HuntingAtlantis, @jessphoenix2018 “uses” the pXRF to "source" the marble used in the buildings of Dhaskalio.

It can't really be used this way

@Jessphoenix2018 and @stelpavlou use the pXRF to scan marble from Dhaskalio, then scan marble from Naxos to compare. Jess declares that the stones are a match, then the two rush off to intentionally sink a rowboat with slabs of marble (presumably to prove a point)

This all looks fine and sciencey, right? Victory for the lab nerds!

EXCEPT

It’s all play acting and doesn’t make any actual scientific sense

pXRF can source stone, if the chemistry is right. With obsidian, you can use chemical differences to find different sources on the same island!

Some materials can be more difficult to work with...

doi.org/10.1016/j.jasr…

Marble’s chemical composition depends on the limestone beds which were originally compressed and heated. The chemical variations can be slight and seemingly random. Even marble from different places can be too similar for pXRF to reliably detect.

This is demonstrated by the 2021 study on pXRF of Aegean marbles by T. Vettor and colleagues, who show the general similarity of pXRF readings between marbles from Naxos, Paros, Tinos, Delos, and Mount Hymmetos. There is a lot of overlap.

You can figure out how different stones are similar using statistics, but notice how the groups overlap. Could you tell the points apart without the nifty color guide?

Try to find 2 different sources inside the circle.

Now imagine if you could only see two of the points...

The sources overlap. For some perspective, here they are on a map, the area between them is roughly 2,400 square miles. So how did @jessphoenix2018 look at 2 samples, without any comparison or analysis, and decide that the marbles were “a match?”

...By the way, when @jessphoenix2018 comments about cobalt and titanium and copper being at the right level… those elements aren't useful for sourcing marble with a pXRF.

Did she just name two random elements?

Yes, it appears she did.

So,
Is the marble from Naxos? Probably, but that work was already done by John Dixon and published in 2013. This was done by observing the physical characteristics of the marble on the islands near Dhaskalio. It’s chapter 14 of the excavation volume

aegeussociety.org/new_book/the-s…

Did @jessphoenix2018 and @stelpavlou know about this work? Probably, its likely where they got the idea to go to Naxos...

But, if their job is to present scientific research, why did pretend to use pXRF to pretend to make the discovery themselves?

Answer: It’s entertainment
They don’t worry about science. Like the characters on CSI, who look at a computer monitor and announce the killer wears glasses, doesn’t like pickles and drives a moped.

It doesn't need to be factual, just entertaining.

In reality, science doesn’t work that way. If you only look at the marble from Dhaskalio and the marble from Naxos, you don’t know how different Naxos is chemically from other marbles (which it isn’t, as we already discussed). It’s a pXRF, not a Crystal Ball.

Still inclined to believe the ‘science’ in #HuntingAtlantis? Remember episode 6 where @jessphoenix 2018 says the marble has a “really distinct chemical signature?”

The machine is showing that it can’t detect any chemical signature at all:

There is lots of good geological science out there for everyone to learn about, #HuntingAtlantis just doesn’t care enough to use it as anything but window dressing. To them, the science machines are just for make-believe.

https://twitter.com/NASAPersevere/status/1436366199424569346?s=20

But, if you’re looking for some good fantasy television, IMDB recommends #HuntingAtlantis

It’s up to you!

Stay tuned for more #Science of #HuntingAtlantis

Thanks to @FlintDibble for the inspiration

Here are the works I referenced:
T. Vettor et al., 2021. Delos archaeological marbles: a preliminary geochemistry-based quarry provenance study, archaeometry
J. Dixon, 2013. “Chapter 14: The Petrology of the Walls,” in Renfrew et al. (eds) The Settlement At Dhaskalio

For a look at the debate and some of the issues with #HuntingAtlantis and Atlantis in general check out this thread by @FlintDibble

https://twitter.com/FlintDibble/status/1393689542914359297?s=19