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This climate scientist has tried really hard to get a date

Posted on 15 February 2016 by howardlee

Seth Burgess has, literally, travelled to the ends of the Earth to find a date. Along the way he has endured attacks of giant flesh-eating bee-flies, paddled a raft 60 miles in driving Siberian rain, braved volcanoes in Alaska, and inhaled polluted air in China for weeks on end, all the while hauling pounds of rocks. And all in the name of Science.

The date he seeks plays extremely hard to get.

In Siberia, Seth and his colleagues whacked off rocks from cliffs in dozens of mosquito-infested riverbanks scattered across over a thousand miles of Siberia, and hauled them back to MIT in Massachusetts. He pulverized his rocks to free tiny zircon crystals and then baked them before bathing them in ultra-pure hydrofluoric acid (an acid so powerful that it dissolves glass) for two days. He then took his cleaned-up gems to the University of Arizona, where he inspected each and every tiny grain under a microscope and then zapped it with a laser and sucked the vapor into a machine called a “LaserChron.”

Sadly, not a single gem was worthy.

“So all that work really for naught!” Seth told me when I met him in the American Geophysical Union meeting in San Francisco in December.

The date Seth was pursuing was the age of the most cataclysmic event to hit the Earth since animals evolved. No, not the end-Cretaceous when the dinosaurs were annihilated, a much bigger catastrophe even than that: the end-Permian mass extinction, when more than 90% of species ceased to exist. It was a time when severe global warming made oceans as hot as the legal limit of a hot tub, and gasses from Siberian volcanic eruptions were the suspected culprit. To convict the eruptions, Seth needed to see if they occurred just before the mass extinction, at a precision never before achieved.

Obviously it makes sense if you want to date the onset of the eruption and tie that time in Earth history to when the mass extinction occurred, you want to date the first stuff to erupt. 

But that stuff formed so explosively that it’s now a jumble of volcanic ash and shattered sediments, and unfortunately for Seth it turns out that those sediments brought with them all those unworthy zircons. Seth told me,

There were zircons that ranged in age from about 260 million years old to 2.5 billion. It’s just a hodge-podge of stuff.

The Ugly Stepsister

Undeterred, Seth moved on to find a date for the 2 ½-mile-thick, thousand-mile-wide layer cake of the Siberian lavas. But the lavas had no zircons, so he had to settle for perovskite crystals instead.

So we had to go to kind of like the ugly stepsister. But in the absence of the cute sister maybe the ugly sister is not so bad! You’re hard up, so that’s where you’ve got to go!

To cut a long story short, Seth did get his date – several in fact. Some of them were actually from zircons extracted from volcanic ash he found sandwiched between layers of lava.

And what those dates proved was that an unconscionable quantity of lava erupted in what geologists call a ridiculously short period of time – about 300,000 years or less - and yes, right before the mass extinction. The eruptions delivered a huge slug of greenhouse gas to the atmosphere, far more than humans could even if we were to burn all our fossil fuels, which explains the hot tub ocean temperatures. The eruptions were so relentless that there wasn’t any time for soil to develop between lava flows.

It’s a similar story in Antarctica, where lavas of the “Ferrar Large Igneous Province” have been tied to a minor (but still global) mass extinction known as the Toarcian Extinction.

Every single rock I dated from the Ferrar, and we’re talking up the mountain, down in the ravine, from one side of the continent to the other, along the Transantarctic Mountains - they’re all 182.6 million years old! It’s every single rock the same! And we’ve already talked about how much work it is to date one frigging rock! And when I date 22 of them and they’re the same age, and they’re from all over the place in the Transantarctic Mountains it gives me a great sense of: it’s all in one shot! It’s not a big slow prolonged event.

Seth’s dating quest, and similar travails by other geochronologists, have now proven the close link in time between several mass extinctions in Earth’s past and huge eruptions, including for the end-Cretaceous extinction that wiped out the dinosaurs. In that example geochronologists have tied the famous Chicxulub asteroid impact date to the same time as gargantuan eruptions in India, suggesting that the impact may have aggravated the eruptions. So it seems the dinosaurs were extinguished by the original “double whammy.”

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Comments 1 to 8:

  1. Is the plural of "gas" not "gases"?  I can't understand why so many now spell it "gasses".  Mr Moderator, please delete this comment after reading.  I don't wish to cause unnecessary embarrassment.

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  2. Digby Scorgie @1:

    Merriam-Webster: "plural gas·es also gas·ses"

    Collins: "plural gases gasses"

    Oxford: "plural gases or chiefly US gasses"

    wiktionary: "plural gases or gasses" "plural gases or gasses"

    This leaves aside the fact that, in principle, there are no correct or incorrect spellings.  Merely common and less common spellings.  That is the straightforward application to lexical dialects of the well known definition of a language, ie, "a language is a dialect with an army and a navy".

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  3. Digby - I'm a Brit imported into the US, so I'm permanently confused as to which usage belongs on which side of the pond! 2 nations divided by a common language, as George Bernard Shaw said. I have tried to write 'gases' but it just says 'gazes' to me. 

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  4. Pardon me, Howard.  I didn't intend to initiate such a discussion.  However, after consulting my two UK dictionaries (Oxford and Collins), my one US dictionary (Webster's), as well as the latest Fowler's Modern English Usage, I infer an interesting trend:

    Both my UK dictionaries are pre-2000.  They give "gases" as the plural of the noun and "gasses" as the third-person singular, present tense of the verb.  My Webster's is also pre-2000 but gives "gases" as the plural of the noun, with "gasses" as an alternative.  Fowler gives only "gases" as the plural of the noun.

    From Tom's comment I deduce that the alternative US form "gasses" is beginning to push out "gases" as the plural of the noun.  I shall therefore continue to use "gases" but won't complain about others using "gasses" — although you might hear a groan or two from Down Under.

    You have my sympathy, Howard, in your struggles with US versus UK English.  Good luck!

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  5. Digby Scorgie @4,

    I would encourage you to discourage the use of 'gasses' as an alternate of 'gases'.

    It appears the misuse of the spelling 'gasses' is rampant in the englishy speaking lands that rebelled and wanted to be different from original English (mainly the US, a place that even made up a different spacing between rails for trains just to be different, and comically continues to drag out the use of English weights and measures).

    If 'gasses' has a use it clearly is as a verb, along with 'gassed' and 'gassing'.

    Used in a sentence "Timmy often gasses a room to gross out others, and is amused (never to become amuzed) by the sound made will gassing and the look on the faces of others after he has gassed."

    My basis for declaring that it is inappropriate to use gasses as the plural of gas includes the Scholastic Children's Dictionary 2002 edition which only lists gases as the plural of gas. The hope of that book appears to be to correct an incorrect development in the US.

    Other spelling fads of the US rebellious phase should also be 'encouraged to fade away', such as their choice to spell colour as 'color' even though the ending sound of the word is more like fur than for so if they were to be reasonable in their rebellion they would have dropped the 'o' and spelled it 'colur'.

    However, rebellious people often are not reasonable or rational. And pointing out that they are 'going through a phase (never to become faze) of irrationality' often angers them. So be careful how you discourage the use of gasses.

    As for the evolution of language, the way a word is said and the meaning of a word can indeed change, but its written presentation should be a constant. The Chinese understand how important that is. And even English speaking people can understand the importance of always spelling 'roof' the same way even though it can be said in many ways including the 'phonetically spell-able' versions 'reuf' and 'roove'.

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  6. My careless reliance on automated spell-checking resulted in the obvious gaff of 'will' instead of 'while'.

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  7. OPOF @5, you have it backwards.  American English typically is more conservative than the English of Kent (ie, BBC English) just as Yorkshire English also tends to be conservative.  Consequently where American English and "English" English differ, normally it is the language of England that represents the innovation.  In this case, 'gass' may be a last remnant of the middle English spelling customs that gave us manne (for man).

    As for an impossed tyranny of uniform spelling, that makes no more sense (and will be no more successful) than the French Academy.  There are reasons why Chinese characters (at heart pictograms) should not vary over time, while the phonetic alphabet of English should.  If it does not, it becomes arbitrary, and no longer a phonetic alphabet at all.  We will have thrown away the Phonecian's great and lasting innovation in the pursuit of dogmatism.

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  8. Tom Curtis, your link to wikipedia does not clearly explain how the French Academy has not been or is not successful in maintaining standards for the language. Spelling is quite important in French, where mutiple different words can be spelled identically but take different meanings depending on type and position of accents, for instance. This is especially true for verbs, and is of concern regarding semantic. The Academy does produce changes, albeit not at the pace that the populace sometimes would like to see. Those of us who do not struggle with spelling are not bothered by its conservatism. Some minor controversies have been blown out of proportions by the mass media when they have nothing else to talk about. Whereas it is true that phonetic can and should change, I am not opposed to guard against change coming from a generic dumbing down. I find it inapropriate to use the word "tyranny" in these matters. Nobody is suffering much, really...

    Now, back on topic before we get slapped by moderation...

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    Moderator Response:

    [PS] Indeed, lets not have a grammar/spelling discussion.

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