[meteorite-list] puzzling Putorana
From: Matt <Matt_at_meteoritecentral.com>
Date: Thu Apr 22 09:54:10 2004 Message-ID: <004401c1be3a$c645ac40$8fbf7fa5_at_D7220234W2K> Thanks for the comments Allan. One thing I find interesting is the brecciated nature of the basaltic clasts that make up Putorana. Seems odd in basalts. Allan? matt ----- Original Message ----- From: "Treiman, Allan" <Treiman_at_lpi.usra.edu> To: "metlist" <meteorite-list_at_meteoritecentral.com> Sent: Monday, February 25, 2002 1:06 PM Subject: RE: [meteorite-list] puzzling Putorana > Hi, all - > > With Matt Morgan's help, we've just finished a paper > on the Putorana rock, and it should be published in > July (?) with the Meteoritical Society meeting abstracts. > The paper is bigger and more formal than the article(s) > in Meteorite . If you'd like a preprint, send me your email > or postal address! > > Personally, I'm not real keen on the Putorana iron coming > from the Earth's core. It seems like an awfully long way for > heavy stuff like iron metal to rise (or be carried up). > The Diskoisland metal supposedly formed when molten basalt > hit coal seams. The reaction was like smelting - iron oxide in the > basalt magma reacted with the coal, and produced iron metal. That > doesn't seem to work for the Putorana stuff, as the basalt is too rich > in iron -- if iron had been smelted out of it, the basalt would be poor > in iron. > My current guess is that the iron metal came from iron sulfide > liquid. There's a lot of iron sulfide ore in the Putorana/Noril'sk area, > so having sulfide is not a problem. Perhaps the sulfide could get > "roasted" naturally, and drive the sulfur off into the air. The iron would > be left behind as metal. Just an idea. Perhaps our Russian friends > know more about Putorana?? > > Cheers! > Allan > > Allan H. Treiman > Lunar and Planetary Institute > 3600 Bay Area Boulevard > Houston TX 77058-1113 > 281-486-2117 > 281-486-2162 FAX > treiman_at_lpi.usra.edu > > > -----Original Message----- > From: Dave Harris [mailto:entropydave_at_ic24.net] > Sent: Saturday, February 23, 2002 3:17 AM > To: metlist > Subject: [meteorite-list] puzzling Putorana > > > Hi there, > I have just read Mr. Norton's article in this quarter's Meteorite magazine > on Putorana where he speculated that the iron in the basalt was derived from > mantle plumes conducting iron from the core to the magma chambers in the > lithosphere - I was just wondering how actually plausible that mechanism > actually was. > I thought that a more likely scenario for the creation of Putorana iron may > have been the effect of a magmatic plume coming into contact with a highly > carbonaceous sedimentary deposit and the iron compounds are then reduced to > native iron (much in the same way that commercial iron is produced by > reacting with coke). I accept that the sedimentary deposits would have to > be subducted to quite some depths before the appropriate temperature and > pressures arose, but it still seems more likely a scenario to me than a > outer liquid core streamer of iron travelling a couple of thousand > kilometres upwards, against gravity and still keeping the iron in a liquid > enough state to mix with magma. > > Any ideas? I wonder if there is any overriding chemical evidence that the > iron is sourced from the core rather than liberated as part of a reduction > of mantle silicates and oxides (possibly the presence of Ni in the iron is > the evidence that supports the core theory - I dunno!) > > Don't laugh at me if I have written a load of rubbish here! I need to learn > and only by thinking about this stuff and making gaffs will I learn > anything - some of you people out there know more about Geology than I will > EVER learn, so I bow to your undeniably profound knowledge!!! > > Ideas/opinions please! > > -- > In gentle decay, > dave > > IMCA #0092 > > imca_0092_at_hotmail.com (for IMCA member contact) > > http://www.meteorites.ic24.net/index.html > > http://www.meteoritecollectors.org > > "I have a proof that x^n+y^n=z^n never has integer solutions for n>2. > However, it won't fit into my signature file...." > > > > > > > ______________________________________________ > Meteorite-list mailing list > Meteorite-list_at_meteoritecentral.com > http://www.pairlist.net/mailman/listinfo/meteorite-list > > ______________________________________________ > Meteorite-list mailing list > Meteorite-list_at_meteoritecentral.com > http://www.pairlist.net/mailman/listinfo/meteorite-list > Received on Mon 25 Feb 2002 03:26:52 PM PST |
StumbleUpon del.icio.us Yahoo MyWeb |