Re: Green River varves

Arthur V. Chadwick (chadwicka@swac.edu)
Thu, 08 Jan 1998 21:41:02 -0800

At 10:09 PM 1/7/98 -0600, Glenn wrote:

>But my impression of what you were saying was that Pittock showed that there
>was no weather/sunspot connection which would invalidate therefore the
>connection between the Green River varves and the sunspot.

What Pittock did show was that any demonstration of such a correlation is
going to be extremely tenuous, and not something you can build a whole
world view around.

>There was the contention that there is not a demonstrable connection which I
>believe Currie may have disproven.

He only said that from his perspective it would be better for science and
ecology if most of the papers written on correlations were never published.
I think Currie's work only makes his case more certain, because since you
have read at least one of his papers, you are aware of the lengths he had
to go to to establish his points. Unless you find a Green River paper that
has used this kind of rigorous treatment, I think you can with Pittock,
safely dismiss the work as inconsequential.

>Wait. Lets turn the question around. One can count the layers in the Green
>River whatever they are.

But you can't really, at least, no two counts of large sequences will be in
agreement. All you have to do is look in the photos of one of the papers I
cited, say Ripepe's fig. 2 to get an idea how impossible objectifying the
data becomes.

Now if they vary every 22 layers (11-couplets) why
>would this not be evidence that they are varves that is yearly deposits?
>What other natural system produces this type of cyclicity? We do see it in
>the fossil record. A friend of mine found a fossilized tree in Oligocene
>from S. Texas. He sliced a slab for me and I measured the rings and did a
>fourier spectrum on them. There was an 11 ring periodicity. If the sunspot
>cycle can be found in tree rings which respond to weather, why not lake
>deposits?

At least with tree rings, we have some historical precedent for an annual
phenomenon that today does respond to the solar signal. As far as I am
aware, no such modern analog exists for the Green River sediments.

>However Bennet's work seems to do a good job of finding those cycles. See
>his figure with the powerspectrum.

Which makes me suspect (ala Pittock) that maybe he wanted them badly!
Where is his raw data? I would like to challenge you to do a CRITICAL
analysis of his methods and conclusions (critical, since you already like
his conclusions), since you are by your own admission, an expert in this
area, and I am certainly not.
Art
http://chadwicka.swau.edu