[meteorite-list] Dino killer size
From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Fri, 11 Apr 2008 16:08:42 -0500 Message-ID: <01b301c89c18$38e614d0$8250e146_at_ATARIENGINE> Hi, EP, List, I think the method will prove valuable. Tho I know little of the chemistry of osmium, they say that, once vaporized, it goes "with" the atmospheric moisture and is rained out and ends up in the muck. The iridium distribution is spotty and hard to find, but ocean (and lake) muck is widespread. Now that they've found the cosmic osmium where we expect it to be, I want'em to look for osmium-188 spikes (or enrichment) in some long sedimentary cores from geologically more recent times for evidence of impacts we are unaware of, or only suspect. Sterling K. Webb ------------------------------------------------------------------- ----- Original Message ----- From: "E.P. Grondine" <epgrondine at yahoo.com> To: <meteorite-list at meteoritecentral.com> Sent: Friday, April 11, 2008 11:46 AM Subject: [meteorite-list] Dino killer size Hi Sterling - I would imagine a lot of the cosmic osmium would have been "sequestered" in the impact spherules. The KT fossil meteorite seems to have been ignored by this group, so How would you determine the composition of what hit? First, take samples from around the crater. Then working from known densities and crater size, estimate your velocity. That said, the idea of using osmium ratios as a way of detecting impacts to have occurred looks valid. E.P. Grondine Man and Impact in the Americas __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ______________________________________________ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list at meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Fri 11 Apr 2008 05:08:42 PM PDT |
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