This damned tephra problem

I hate to bore my usual readers with research problems but... I'm having a research problem.

I've been mulling over the slides from the Drangajökull outlet glacier core microtephras for some time now, but this week I've finally been able to focus on the problem (as I was microprobing other samples last week). Basically the microtephra from the peat core taken near the outlet glacier comes in three varieties: generally silicic, generally mafic, and then crazy microlite-studded bright orange. My samples from the archaeological peat core, and from the lake, which were cored about 5km away as the crow flies, have the first two -- and absolutely nothing like the third.

My first guess is that the orange colour is the result of some chemical leaching in the soil. I found a paper a few minutes ago that might tell me more about it but it's 11pm and my brain is fried so I'll check it in the morning.

The microlites are a more serious issue. They indicate that the microtephra has come from a source close by -- but the archaeological site is closer to any source volcanoes than this core. And if the tephra was transported by air, then it should have fallen in both places anyway. The presence of the glacier might create a rain shadow? Or something like that? Or meltwater pulses? I'm trying to come up with any reason why this might be the case. I need to come up with something convincing and interesting, however, because I'm giving a paper at the GSA on Halloween and part of it has to do with this research.

Blergh!

Someone is wrong on the internet!

I know I should never, ever read internet comments but sometimes I just can't help myself. My eyes drift downwards, past the bottom of the article* and onto some comments, and I get sucked in... and sometimes I see one so incredibly dumb that I think it deserves an award... so get ready for a heady dose of anti-scientific, anti-British, anti-intelligence.

The original story was this one, about how Easyjet, in conjunction with Airbus and a Norwegian scientist, have come up with a new type of detector for volcanic ash. The video is kind of terrible (the male presenter is a huge jackass), just to warn you, but does feature a bag of tephra (awesome!).

Then some... thing... calling itself ephrim wrote this comment:

ephrim

Quote"This pioneering technology is the silver bullet that will make large scale ash disruption history"Unquote Chief Executive Andy Harrison. Has it ever occurred to theBrits that this new technological discovery is the very thing is what caused the erruption in the first place? give or take a fe... more

Quote"This pioneering technology is the silver bullet that will make large scale ash disruption history"Unquote Chief Executive Andy Harrison. Has it ever occurred to the
Brits that this new technological discovery is the very thing is what caused the erruption in the first place? give or take a few modifications. I would strongly suggest that the British Authorities and whoever else is involved in this new discovery should go back to the drawing board and think this one over and when they have done that I think they
should sit down with BP and realize that there may be ONE common denominator in
this ointment!!! Oil Bloody Blaaah Da.
and think this one over less

19 hours ago | Like | Report abuse

Ding ding ding ding ding ding ding ding ding

DING DING DING DING DING DING DING



*Luckily this never happens on youtube, because there is no scrolling involved. THANK GOD.