Re: marine or eolian dunes?

Arthur V. Chadwick (
Tue, 03 Feb 1998 07:51:03 -0800

At 08:51 PM 2/2/98 -0600, Glenn wrote:

>Not so fast. :-) Brand has never explained to me why there are tracks which
>have the appearance of scorpion tracks on the Coconino. And even more
>troubling is the fact that scorpions leave a different type of track as the
>temperature rises. We find tracks that look just like the tracks scorpions
>make when it is cool and then when it is very hot. There are fewer feet in
>contact with the sand when it is hot. Since the temperature wouldn't rise as
>much in a subaqueous environment, I see no reason to ascribe those tracks to
>a hot-footed underwater scorpion. So I don't think the issue is as moot as
>you do. But good try. :-)

That work was done in the 1940's, before anyone had even thought of
subaqueous for Coconino. If you had read Brand and Tang (and especially
Tang's thesis), you would see that all these issues have been adequately
addressed. The trackways of the "arthropod" (which could as well be
crustacean as a scorpion), could not possibly have been made on dry sand,
since the distinct marks could not have survived on a foreset slope of a
dune in dry sand. They were probably made by a crustacean under water,
where identical tracks can be formed in the laboratory underwater, but not
on dry sand.

>I don't think glauconite implies deepwater deposition. It is found quite
>abundantly in the coastal plains sediments of the eastern United States and
>those are generally considered to be relatively shallow water deposits. But
>they were MARINE. (see N. Spoljaric "Geology of the Delaware Coastal Plain",
>in John C. Kraft and Wendy Carey, ed. Trans. Delaware Acad. of Sci. 7, 1976,
>pp 93-95)

You stand nearly alone on that one. In the modern environment, the
formation of glauconite requires deep water. If you want to suggest that
in the past, glauconite was formed in shallow water (as Chafetz has done in
his article you would love, "Depositional, shallow water precipitation of
glauconite: the present is not the key to the past" in GSA Abs w
prog:28:109) the burden of proof is on you. To say that a supposed shallow
water deposit containing glauconite is proof that glauconite formed in the
past in shallow water without reevaluating the basis for the attribution of
"shallow water" does not help. I reassert: glauconite is a deep water
environmental indicator.

>Please continue. That is hardly enough to explain these things. It seems to
>me that there is more of a problem with mixing in a global flood when
>everything is supposed to be eroded from the preflood world, then
>redeposited. Surely there was some mixing of lime and clastics the likes of
>which we don't see in an actualistic or uniformitarianistic world.

Really, I was trying to get an explanation out of you... I have no
difficulty with nothing happening for 260 million years if it was not 260
million years. On the other hand, the Nubian SS gives us a chance to
reevaluate everything about the nature of the fossil record and the meaning
of the geological column. I am working on that.