Re: "Meteor theory gets rocky ride from dinosaur expert"

[Phil Bigelow <bigelowp@juno.com>]

America's first manned space flight was a sloooowwww suborbital flight,
and it lasted around 15 minutes.  It is likely that most of the Yucutan
ejecta flew a much faster suborbital tragectory, with a smaller chunk of
the Yucutan Peninsula actually going into orbit.  (the K-T spherules
found in the northern U.S. may have actually achieved full orbital
velocity).

The great circle route distance from Chicxulub to the Brazos River is
sufficiently large that the suborbital ejecta would arrive before the
arrival of the marine wave form. So it is possible that some reworking of
a *portion* of the largest spherules had occurred.  But the backslosh
(carrying the bulk of the eroded Cretaceous mud) would have returned
hours later, burying everything.  Superpositioning would have dominated
the scene.  ;-)

<pb>
--


On Fri, 27 May 2005 09:10:41 -0500 jrc <jrccea@bellsouth.net> writes:
> 
> ----- Original Message ----- 
> From: "Tim Donovan" <uwrk2@yahoo.com>
> To: <dinosaur@usc.edu>
> >  Lehman wrote that the southern end was closed by
> > middle Maastrichtian time, and mentioned an incipient
> > Cannonball Sea. Btw, wouldn't a tsunami have wiped out
> > the ejecta layer if it struck immediately afterwards?
> 
> The paper about the South Dakota tsunami deposits suggests that it 
> was still 
> open, and another paper about the SE Missouri deposits suggests that 
> it was 
> open there as well.  I don't presently have a strong opinion about 
> that.  Am 
> curious, though.
> 
> A tsunami wave would be expected to disrupt some or all (depending 
> upon the 
> geometry) of the early ejecta deposits and then redeposit them 
> during the 
> backwash wave, to give multiple ejecta layers, some segregated, some 
> 
> chaotic.  This could be expected to happen several times, as there 
> would be 
> more than one tsunami wave associated with the event.
> Jim 
> 
> 
> 
>