Huh. I wish I could find an actual paper about this rather than summaries and the abstract. I can't tell from what they're suggesting it started the P-T event or just contributed to it. The extinction started sometime before the actual boundary and the break up really happened after, so I'd love to know how accurate the dates on this crater are. Regardless, I find myself reluctant to trust these things until I've at least seen the paper. Funny that Science and Nature didn't seem to mention it in their news sections in the last couple of months - they normally mention stuff that's big in the editorial news pick bits.
The big thing with the P-T is that none of the explanations thus far explain all of the trends we see in the rock record. Most of them are covered by a combination of potential triggers (climate change due to supercontinent formation and the impact that had on ocean circulation patterns, also possible alteration in mass balances due to change in drift dynamics, likely massive volcanism also linking to climate change etc). So if this is what actually triggered those triggers, it's a pretty cool finding. It's still a pretty cool finding, but less big if it's just a contributing factor etc. I can't remember if anybody's suggested anything like the iridium anomaly at the K-T around the P-T before, though I think with the other crater there were some argon isotopes or something as well as impact breccia, but I seem to remember it was fairly local.
On an ironic note, a guy who was really condescending at me at a conference a couple of years ago has just had a book published about the P-T extinction and the debate over it, so I imagine he's not best amused by the timing! It's apparently a good book, I was planning to get hold of a copy at some point as it's a really interesting area.
Thanks for posting this! I've not read the BBC news science section for a while, which is quite unusual for me actually. That and the tennis page are the only bits I read on a regular basis!
Sorry, I have to have a geology 101 TA moment here.... I'm sorry! 200Mya when Pangea started to break up was the end of the Triassic, not the P-T. Pangea had just formed at the P-T. Also, Pangea was the supercontinent that broke up - Gondwanaland was just a piece that broke off, the rest was Laurasia. So technically it's the break up of Pangea or the separation of Gondwanaland and Laurasia.
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timeasmymeasure
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Date: 2006-06-08 04:04 am (UTC)The big thing with the P-T is that none of the explanations thus far explain all of the trends we see in the rock record. Most of them are covered by a combination of potential triggers (climate change due to supercontinent formation and the impact that had on ocean circulation patterns, also possible alteration in mass balances due to change in drift dynamics, likely massive volcanism also linking to climate change etc). So if this is what actually triggered those triggers, it's a pretty cool finding. It's still a pretty cool finding, but less big if it's just a contributing factor etc. I can't remember if anybody's suggested anything like the iridium anomaly at the K-T around the P-T before, though I think with the other crater there were some argon isotopes or something as well as impact breccia, but I seem to remember it was fairly local.
On an ironic note, a guy who was really condescending at me at a conference a couple of years ago has just had a book published about the P-T extinction and the debate over it, so I imagine he's not best amused by the timing! It's apparently a good book, I was planning to get hold of a copy at some point as it's a really interesting area.
Thanks for posting this! I've not read the BBC news science section for a while, which is quite unusual for me actually. That and the tennis page are the only bits I read on a regular basis!
Sorry, I have to have a geology 101 TA moment here.... I'm sorry! 200Mya when Pangea started to break up was the end of the Triassic, not the P-T. Pangea had just formed at the P-T. Also, Pangea was the supercontinent that broke up - Gondwanaland was just a piece that broke off, the rest was Laurasia. So technically it's the break up of Pangea or the separation of Gondwanaland and Laurasia.