Re: Volcanoes (comments on pterosaur extinction)

["Ken Kinman" <kinman@hotmail.com>]

Emma,
     Since I'm not a geologist, I don't know if this will make sense, but 
what about the following scenario:
     1.  Bolide crashes into the Earth.
     2.  Deccan traps triggered to erupt.
     3.  Iridium (etc.) rains down on top of these
         initial lava beds during the following
         weeks and months (years??).
     4.  Iridium layer is then covered by subsequent
         eruptions, and thus sandwiched between
         layers of lava.
Is such a scenario possible (and if so, very probable)?    I suppose someone 
has proposed such a scenario, but I'm not sure what the arguments might be 
against it.
                    Cheers, Ken
*******************************************************
> From: "Emma C. Rainforth" <emmar@ldeo.columbia.edu>
> Reply-To: emmar@ldeo.columbia.edu
> To: dinosaur@usc.edu
> Subject: Re: Volcanoes (comments on pterosaur extinction)
> Date: Wed, 7 Feb 2001 15:51:29 -0500
>
> except, the iridium layer and all other impact-related features occur
> in the MIDDLE of the Deccan.....i.e. the Deccan traps were already
> erupting before the bolide hit.
>
> BTW, the Triassic-Jurassic mass extinction PREdates the central
> Atlantic magmatic province (which is bigger than Deccan). So the
> volcanism can NOT have caused this extinction event.
>
> Emma
>
> Ken Kinman wrote:
> >     I don't know much about geology, but it seems likely to me that
> > the bollide collision probably set off a lot of the volcanic
> > activity, and that this just added insult to injury and vulcanism
> > was of secondary importance overall.
> --
> Emma C. Rainforth
> Geosciences Rm. 206E
> Lamont-Doherty Earth Observatory
> Rt. 9W
> Palisades
> NY 10964-8000
> ph. (845) 365-8621
> fax (801) 838-4126
> emmar@ldeo.columbia.edu
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