> >There is a similarity with the Haymond deposits in that the tsunami
> >deposited consisted of two layers: the bottom one of sand, the top one
of
> >clay/silt. To be sure the quantities of each are certainly different
than
> >the Haymond deposits.
>
> Yes, there are several differences. As you note, the quantities of sand vs
> shale are different in the tsunami deposit. There is the lack of marine
> burrows in the tsunami deposit which exist in the Haymond. And most
> importantly, the Haymond consists of 15,000 layers, the tsunami consists
of
> one pair with very, very little shale. Now, if the tsunami had deposited
> 15,000 layers of sand and shale then you might have a case. As it is, you
> will have to wait several hundred years for the next tsunami at that spot.
> The tsunami simply is not analogical to the Haymond.
I was only making a comparison between the particle makeup of the tsunami
deposit and the make-up of layers of the Haywood formation. The lack of
burrows, the number of layers, and the timing the tsunami are separate
issues that need to be addressed, but not till later. I am merely making
the case at this time that tsunami depositions and turbidite depositions are
similar.
> >Lets start with point 1.
> >In this case, as the tsunami swept ashore it picked up beach sand
> >and nearly
> >simultaneously deposited it as it swept inland. What if, instead
> >of a sandy
> >beach, the wave had swept across a muddy delta? What would be the major
> >load carried by the wave? What would be the major deposition?
Obviously,
> >clay/silt.
>
> True, but most of it would have remained suspended in the draining waters
as
> Stoke's law would not let it settle as rapidly as you require for a global
> flood.
Whether or not most of it would drain off would depend upon whether we are
talking about a thick slurry of clay or about a few particles of clay
suspended in tons of water.
> There are several tsunami's per year. Find one with little sand and lots
of
> clay. I don't think you can.
Due to the 1964 Alaska Earthquake, three tsunami waves (up to 7 m high)
swept ashore over the Somass River delta in Port Alberni, Vancouver Island,
BC. Scientists dug pits and sank cores obtaining measurements of tsunami
depositions.
Tsunami 3
~11 cm of clay/silt
1-2 cm of sand
setting on top of:
Tsunami 2
20 - 70 cm of clay/silt
~5 cm of sand
setting on top of:
Tsunami 1
45 - 130 cm of clay/silt
12 - 68 cm of sand
Clague, J.J. and Bobrowsky, P.T. 1994, "Tsunami Deposits beneath tidal
marshes on Vancouver Island, British Columbia" GSA Bulletin. v. 106, pp.
1295-1297. (It is really wierd but they actually think that the three huge
waves made only ONE (1-2 cm) deposit AND that the one deposit was ONLY SAND!
Yet they admit that there was only deltic depositions below the lowest of
the three mud/sand pairs.)
I think I can!
> >Point 2.
> >One of the major means of identifying turbidite deposition is the fact
that
> >it has normal grading (although reverse grading is sometime noted), from
> >sand through silt to clay. At the New Guinea tsunami deposition site the
> >deposit displays "normal grading" (including clay/silt on top). This
> >confirms an off hand statement from a non-creationary geologist I
> >heard once
> >who said that tsunami and turbidite depositions were nearly
> >indistinguishable.
>
> Unnamed sources, like with newspapers, are untrustworthy. Sources please.
Let the facts speak for themselves. They are more important than an
off-hand remark told to me.
> >Point 3.
> >The tsunami deposition also display landward fining. It is curios to
note
> >that ALL Grand Canyon formations display horizontal fining in one
direction
> >or another. I wonder if anyone has checked to see if the Haymond
deposit
> >layers graded horizontally. I would not be the least bit surprised to
find
> >that they do grade horizontally.
> Of course they grade. Almost all clastic beds do. That doesn't mean that
the
> Haymond was a tsunami deposit. Your tsunami deposit has little shale and
no
> burrows.
Obviously there are no burrows! One would not expect there to be burrows
from EVERY turbidite, nor from EVERY tsunami. And I did not bring up the
New Guinea tsunami deposits in order to make burrow comparisons. I am just
discussing the grading of the material and the fact that mud is a part of a
tsunami deposit.
> >> Thirdly, this is a tsunami deposit which is above sea level which
allows
> >the
> >> shale-containing water to flow down through the porous sand as noted
> >above.
> >> Below sea level, this won't happen. The water will not flow through the
> >sand
> >> like it does on land.
> >
> >This is a good point. I like it! It makes deposition of clay/silt even
> >faster than I had thought. It is still note worthy that the clay/silt
was
> >there because the tsunami picked it up and carried it into place.
>
> Don't jump on it for a marine deposit, which is what the Haymond is.
> Landslides on land don't sort the way that turbidites do. In the water,
the
> turbulence separates the shale from the sand with the sand flowing close
to
> the water bottom and the shale going into suspension and depositing over a
> vastly larger area. Only over a long time can shale be deposited on top of
> the sand in a marine environment. An onshore landslide simply mixes
things
> up with little sorting.
This is entirely contrary to the evidence of tsunami deposits we have just
been discussing. The sand and clay/silt are also separated in a tsunami
wave. Pure, graded sand is deposited beneath pure, graded clay/silt all in
one pass. And it cannot take a long time for the graded clay/silt to be
deposited because a tsunami is only on shore for a fairly short time. The
reason why clay/silt can be deposited so quickly is simply because the
consistency of the tsunami wave more resembles a thick slurry (mud) than the
clarity of your local swimming pool.
The same goes for turbidites. The clay/silt is deposited quickly because
the turbidite is primarily a thick slurry of mud. And, this does not
violate your precious Stokes law.
> Tsunami's and turbidites are distinguishable. ....
> Geologists can tell the difference between marine and land deposits and
> between tsunamis and turbidites.
>
> This is from R. Peters et al, ITS 2001 proceedings "An Overview of Tsunami
> Deposits along the Cascadia Margin," p. 479
> http://www.pmel.noaa.govits2001/Separate_Papers/3-03_Peters.pdf
>
> "Tsunami deposits may be distinguished from river deposits by distinct
> biological markers, spatial distribution, sediment characteristics, and
> geochemistry. Tsunami deposits contain marine or brackish water macro-and
> microfossils while fossils in river deposits, if present, would be fresh
> water varieties. Tsunami deposits fine landward, while river deposits
> generally fine seaward. The composition texture of the sand grains can be
> used to determine a coastal or upriver source. Geochemical indicators,
such
> as bromine enrichment, may indicate a marine source."
Great quote. It illustrates another important difference between the
typical geologist and Creationary Catastrophist geologists. This has to do
with the proposition that a specific sedimentary facies corresponds only to
specific lithofacies representative of specific depositional environments.
Sedimentary environments fall under three major categories, 1) Continental,
2) Marine, and 3) Transitional according to particular sets of chemical,
physical and biological characteristics. For instance, assuming that the
chemical and physical characteristics are the same (or very similar) for two
sedimentary facies, the lithofacies would be determined by whether the
biological characteristics (i.e. fossils) were Marine or Continental. This
assumes that at the time of deposition there was a distinction between
Continental, Marine, and Transitional environments. However, during a
global flood catastrophe such distinctions would be meaningless. The
fossils found in tsunami deposition would not be indicative of anything
other than that those animals just happened to be in the tsunami load at the
time of deposition.
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