Art, the last time you and I crossed swords on this issue, we agreed that
Buchheim was working at Fossil Lake, not Lake Gosuite. (see Paul Buchheim,
"Paleontological and Sedimentological Variation in Early Eocene Fossil Lake"
contributions to Geology, University of Wyoming, v 30 May 1994),circa p.
42). The data I presented and the Cyclicities were from two cores taken
from Lake Gosuite and these two wells are respectively 140 and 190 miles
from Fossil Lake. Since the local geology of these two lakes is different
and is recognized so by the USGS (they are named different members) it is
not correct to use Buchheim's Fossil Lake data and apply it to the Lake
Gosuite deposits. Isn't it true that the tuffs you mention are in the much
smaller Fossil Lake? Has Buchheim published anything on Lake Gosuite that I
am unaware of?
We simply must be clear about this distinction and about which Green River
members one is talking about. The data I submitted was about Gosuite, which
we shall see is not as subject to storm-laminae as is Fossil Lake.
For those who might not know the Green river formation consists of several
lake deposits. Fossil Lake is an approximately 16 mile in diameter lake
that is west of Lake Gosuite. I agree with Art that the Fossil Lake varves
are not yearly varves. There are more "varves" between the two tuffs as one
gets nearer to the lake's former shoreline. (see Figure 10 of Paul Buchheim,
"Paleoenvironments, lithofacies and varves of the Fossil Butte member of the
Eocene Green river Formation, Southwestern Wyoming," Contributions to
Geolgoy University of Wyoming, v. 30, p. 11) Thus what we have is near the
shore where there are more laminae you have
total laminae = storm laminae + yearly laminae
In the basin you have
total laminae = fewer storm laminae + yearly laminae
The extra varves are storm-laminae from runoff from individual storms.
Lake Gosuite is about 200 miles in diameter and thus the storm runoff is
more likely to settle out before it travels 100 miles to the quiet center of
the Gosuite basin where the organic rich, highly laminated oil shales of the
Tipton and Laney members are to be found. Indeed due to the lack of
sand/shale input the laminae are chemically organic rich kerogen and
predominately carbonate. (See Fischer and Roberts, "Cyclicity in the Green
River Formation (Lacustrine Ecoence) of Wyoming, Journal of Sed Pet, 61:7 p.
1147.) The Fossil Lake Green River laminae are called the Fossil Butte
member and these laminae have a much higher input of clastics (sand/shale).
Buchheim writes:
"Towards the lake margins the micrites grade laterally into fine-grained
siliciclastics including claystones, siltstones and sandstones." p. 6 of
buchheim, Contr. to Geol. Univ. wyoming, 30:1
and
"The sandstone tongue grades basinward into laminated micrites that are
unusual in that they are composed of alternating clay and micrite laminae." p. 6
This is different from the Gosuite laminae and supports the storm laminae
problem at Fossil lake.
>Original publication suggest the possibility of 5 and 11 year cycles
>("...by judicious data selection...")in what they viewed mostly as noise at
>other scales. Crowley, Duchon and Rhi (1986) in J. Geophys. Res.
>91:8637-8647.
>Ripepe, Roberts, amd Fischer made astonishing claims for 11 and 5 year
>cycles (1991) in J. Sed. Pet. 61:1155-1163.
>And subsequently extended their claims in a second paper by Fischer and
>Roberts asserting Milankovitch type 20k, 100k cycles (same year) J. Sed.
>Pet. 61: 1146-1154.
>Neither of the latter appeared to be aware of the paper cited in the
>Crowley paper by Pittock (1978) Reviews of Geophysics and Space Physics
>16:400-420. In this paper, entitled"A Critical Look at the Long-term
>Sun-Weather Relationships"
>
Once again Crowley's 1986 paper studied a different part of the Green River
which is the Parachute Creek member in the Piceance basin of Colorado,
rather than what Fischer, Ripepe and Roberts studied in WYOMING in Lake
Gosuite. It simply is not good to say that because one doesn't see a
sedimentologic feature in Colorado, you can't see it in Wyoming. Ripepe et
al, state,
"Crowley et al, studied varved facies, but we suspect that some of these
were not as distal as were the more continuous oil shales of the Tipton and
Laney members and were more likely to record local phenomena such as dust
storms raising the noise level." Ripepe et al, reference above p.1156
If we are going to criticise Fischer, Roberts and Ripepe's work, it would be
best to be sure that we are comparing apples to apples not oranges to apples.
glenn
Adam, Apes, and Anthropology: Finding the Soul of Fossil Man
and
Foundation, Fall and Flood
http://www.isource.net/~grmorton/dmd.htm