On Sat, 15 Nov 2003, Dave Harris wrote: >HI >Mike F., can you explain why you are SO dogmatic >that this Chixculub material cannot not possibly >be what it is because "It is impossible that >metalic material would survive millions of years, >end of story" Isn't that rather a strong statement? >I seem to recall that there are a number of sites >where traces of impactors of about 110mya old >have been found.
The identification of this material is rather suspicious from a number of points. First, a person has to explain how pieces of the Chixculub impactor, presuming significant pieces of it even survived the impact came to be deposited on a Yucatan beach. If a person looks at the published literature, they will find that the crater and impact related deposits are covered by 500 meters (1,600 ft), along its rim, to 900 meters (2,900 ft), within the crater, of Cenozoic strata. Given this depth of burial and the geologic history of the Yucatan Peninsula, it is virtually impossible to propose any rational mechanism to explain how a piece of the Chixculub impactor, which by some small miracle survived being vaporized at impact, could have been transported into surficial sediments where wave action could have exposed it. (Go look at "Subsurface Startigraphy" at: http://palaeo.gly.bris.ac.uk/communication/Hanks/eff.html http://palaeo.gly.bris.ac.uk/Communication/Hanks/Fig5.html ) Second, the closest documented surface exposures of ejecta from the Chixculub impact consists of outcrops of the Albion Formation in northern Belize and adjacent Quintana Roo, Mexico. They form a 65-km long NE-SW trend transect that lies 320 to 365 km from the center of the Chixculub structure. In this case, person needs to explain how a piece of Chixculub impactor was transported from these outcrops to the beaches of Yucatan, where the alleged meteorite was found. Also, the completely lack of any impactor fragments in these outcrops precludes them as possible sources of the alleged fragments of Chixculub impactor. It is possible that outcrops of the ejecta blanket occur as close as 230 km from the center of the structure, but still their distance and lack of any meteorite fragments within them also precludes them as being the source of the alleged Chixculub meteorite fragment. Again, a person would be at a loss to explain how a piece of the Chixculub meteorite ended up on a Yucatan beach. Go look at "CHICXULUB EJECTA BLANKET: NEW INSIGHTS INTO THE KT IMPACT EVENT" at: http://www.museum.hu-berlin.de/min/mitarbeiter/mitarb/frank/paper/schoenian2002berlin.pdf Finally, given the tropical climate of the Yucatan Peninsula, the statement "It is impossible that metalic material would survive millions of years, end of story" is neither as dogmatic nor strong as it is alleged to be. Presuming by some yet unknown process that a piece of the Chixculub meteorite, after also surviving being vaporized during the impact, was seemingly magically transported upward through 500 to 900 m (1,600 to 2,900 ft) of Cenozic limestone and dolomite, it would not have lasted very long in the Yucatan climate. It certainly would not have lasted long being rolling around on a salt water beach. There are cases that pieces of meteorites have survived long periods of times. However, these were under circumstnces vastly different from what a person finds in the Yucatan region. The conditions within the Yucatan Peninsula are quite unfavorable for the preervation of metalic materials. Also, this same problem would occur in arguing that a piece of Chixculub meteorite was eroded and transported from a distance ejecta outcrop. The climate of the Yucatan peninsula is such that weathering would destroy any piece of meteoritic material shortly after it was detached from the outcrop. This and other considerations would indicate the possibility of a piece of the Chixculub meteorite appearing on a local beach to be quite unlikely to the point of being impossible. Mike F. is not at all being dogmatic. Rather, he is expressing a skepticism that is well grounded in what is known about the basic geology of the alleged Chixculub meteorite. A person would have to be as skeptical of this remarkable "find" as they would have to be of someone offering to sell them multiple oil leases within Hawaiian Islands. The validity of both of these interpretations is so grossly contradicted by what is known about the geology of each region that being skeptical of them is nothing more than exercising the common sense that God gave us all. Yours, Paul Baton Rouge, LA __________________________________ Do you Yahoo!? Protect your identity with Yahoo! Mail AddressGuard http://antispam.yahoo.com/whatsnewfree ______________________________________________ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
