Before I start getting all nit-picky, I will point out that two volcanism bloggers, Eric Klemetti at Eruptions and Ralph Harrington at The Volcanism Blog, who know vastly more about the topic than I do, gave fairly respectful hat tips to these reports. They didn't discuss anything in terms of the weaknesses of these (stunningly uniform) reports, though, nor try to clarify the importance of the news beyond the "OMG Super-Terrifying SuperVolcano MegaBlast Eruption Whiz-Bang Crash OMG!!!!" tone of the report(s). And those topics are what I want to address.
Let's start with a look at the photos that accompany the original press release.
This is a basaltic lava flow, very likely from Hawaii. Note that it flows easily (is quite fluid); you can tell because it's thin, flat, and unbroken. Is this a "supervolcano?" Not in the public perception, though it is, as far as I know, the largest active volcanic edifice on the planet. Does it have any relevance (other than being a volcano) to the Permian volcano in Italy? Not that I know of. Why is it included? My guess is that it's a reassuring, stereotypical picture of "lava" in the journalistic mind. Story about volcanoes? Find a picture of runny, red lava.
This is the Yellowstone Caldera. What is the relevance? Both this and the Italian volcanoes are calderas. Yellowstone is the volcano for which I believe the term "supervolcano" was coined for some disaster infotainment show some years back. The term has no defined usage in the geological community, but if the Italian Volcano is a supervolcano, then obviously we have to haul in Yellowstone.
This is the Bishop Tuff. Its relevance is that it erupted from Long Valley Caldera in east central California, the second largest identified caldera in the US (after Yellowstone). We wouldn't want the public to think Yellowstone was the only supervolcano (other than the Italian example, of course).And that's it for the pictures. Notice anything missing? You know, like some photos of the volcanic and magmatic exposures this article is about? A map of the location? A diagram of different zones or composition of the roots and a depth chart? Maybe even a preliminary reconstruction? Nope, none of that.
Why not? Well, duh! The article is about supervolcanoes, not research.
OK, let's take some of the sentences that made me wince, starting with the first: "Scientists have found the "Rosetta Stone" of supervolcanoes, those giant pockmarks in the Earth's surface produced by rare and massive explosive eruptions that rank among nature's most violent events." The Rosetta Stone was an archeological artifact that allowed linguists to begin deciphering Egyptian hieroglyphics. This discovery will not allow us to do that.
"Supervolcanoes, historically called calderas, are enormous craters tens of kilometers in diameter." No. Just no. If eruption of a magma chamber causes the earth's surface to collapse, forming a depression, it's still called a caldera. We haven't renamed every caldera as a "supervolcano." This leads to "Sesia Valley's caldera erupted during the "Permian" geologic time period, say the discovery scientists. It is more than 13 kilometers in diameter." First, Permian should not be in quotes; the correct name is Permian. We're not using it as a euphemism, nor in an unusual or non-standard manner, nor are we quoting the word in the context of a definition. Second, 13 km (~8 miles) is big (a bit larger than Crater Lake, at 6-7 miles), but it doesn't really qualify as a supervolcano. Yellowstone Caldera is 45 X 85 km; Long Valley Caldera is 17 X 32 km. So 13 km radius is pretty puny by comparison, and the Sesia Valley Caldera isn't by any stretch a "supervolcano." But we won't that let that get in the way.
"The exposure also serves as direct confirmation of the cause-and-effect link between molten rock moving through the Earth's crust and explosive volcanism." Really? How? "'It might lead to a better interpretation of monitoring data and improved prediction of eruptions,' says Quick, lead author of the research article reporting the discovery." So "might" equals "direct confirmation?" I guess so. I'm also guessing that molten rock moving through the earth is pretty much by definition associated with all volcanism, not just explosive volcanism.
"Calderas, which typically exhibit high levels of seismic and hydrothermal activity, often swell, suggesting movement of fluids beneath the surface." What do you mean by "often?" And hopefully the caldera nominally being discussed here doesn't show these activities. Of course, these activities can be expected (though not predicted) at any active volcano, and an increase in these activities may indicate an eruption in the relatively near future... or not.
"Bristish researchers introduced the term "supervolcano" in the last 10 years." Well, no; British documentary makers introduced the term in 2000. Wikipedia is not dependable, but it's a good place to start if you don't have any background.
"Besides Yellowstone, other monumental explosions have included Lake Toba on Indonesia's Sumatra island 74,000 years ago, which is believed to be the largest volcanic eruption on Earth in the past 25 million years. Described as a massive climate-changing event, the Lake Toba eruption is thought to have killed an estimated 60% of humans alive at the time." And this is relevant... why? Oh Yeah. Supervolcano. OMG!!!! SUPERVOLCANO!!!!
"Another caldera, and one that remains active, Long Valley in California erupted about 760,000 years ago and spread volcanic ash for 600 cubic kilometers." Yeah, we need to have an example that remains active. Say what? Yellowstone is still active? Yup. And by my quick reading, it would be unwise to assume that Toba is extinct... Then we have "spread volcanic ash for 600 cubic kilometers." I don't even know where to start with that.
Another specific complaint is that the three "supervolcanoes" mentioned occur in differing tectonic settings: Toba (I'm assuming) is a subduction volcano, like Crater Lake. Long Valley is thought to be extensional volcanism, at least last I heard. And Yellowstone (along with Hawaii) is one of the iconic hot spot volcanoes. There is no discussion of the setting of this new one.
Now the fact that RedOrbit picked this press release up and republished it essentially unchanged doesn't surprise me. The fact that NASA's Earth Observatory did, when there are so many obvious flaws, does.
This is why traditional journalism is dying. Reprinting some author's press release isn't journalism. It's not reporting. Press releases are intended to do one thing: get publicity for the sponsoring institution. There might be some important information in them, but if so, it's purely coincidental.
This took longer than I expected, and tomorrow I want to come back to this and point out why it's a fascinating and important story (there are, coincidentally, some important bits of information in it). But I'll close with this thought: The way I learned it, the way to avoid plagiarism was to cite your sources. Note the plural there. If you copy your entire work from a single source (especially verbatim), even if you cite that source, it's still plagiarism. That's what RedOrbit does: they pass along press releases and hope to make some ad revenue by being an aggregater site, and they make no pretensions of being a good site for good science. That's not to say you can't find good science at sites of this type, but you better be science literate and ready with some fairly large bricks of salt if you hope to do so. But NASA, I'm disappointed. Couldn't you have run this through the hands of someone who knows a little geology? Maybe done a follow-up interview? Added a little bit better science? Shame.
Part Two is here.
Clarification and Apology: I have received an e-mail from an administrator at NASA's Earth Observatory responding to what he views as an accusation of plagiarism. Since it is a private e-mail, I don't feel comfortable responding to it in a public forum. I have been pondering all morning about precisely how to respond, which I do feel compelled to do. In the interim though, I did not intend to accuse NASA's Earth Observatory site of plagiarism; the link and attribution to the original press release is clearly provided at the end of the article, nor was the EO in any way claiming authorship of the article. It was, in fact, via the post at EO news that I found the original press release, and I was and am grateful for the link. Whatever meaning I had intended though, looking over the closing paragraphs of the above post, it does seem quite reasonable to suppose that I was accusing EO of plagiarism. To those I may have offended, I offer my sincere apologies.
There are some very serious issues here, though, beyond that of plagiarism, that I think I'll have to address in another post.
Great post! I didn't know until reading this that the in-question Permian caldera was not as large as the many large, Tertiary calderas scattered through Nevada. Here's the show that coined the word supervolcano.
ReplyDeleteMy Time Warp! post goes into "supervolcanoes" a bit, specifically about how I don't really like the word very much, and also about what the USGS and Yellowstone Volcano Observatory have to say about "the word." YVO actually semi-defines the term.
That was a fantastic takedown -- and informative (for a total layman like myself) to boot. Well done!!
ReplyDeleteThe ash was spread over an area of 600 cubic kilometers to a depth of 20 teslas.
ReplyDelete