Hi Kevin,
Sorry to be so slow in responding.
On Thu, 5 Feb 2004 22:38:54 -0700 "Kevin Sharman" <ksharman@pris.bc.ca>
writes:
> Short lived floods wouldn't kill the trees, so they would keep
> growing and churn up the clastic material, resulting in no parting. In
my
> post on petrology I make the point that for a parting to form, the
swamp
> is first drowned by clean water, then the clastics come in.
The clean water drowns the swamp, killing the trees, then the dead trees
fall over flat, then the clastics form a thin layer, then the clean water
drains (due to uplift?) without eroding the thin layer of soft clastic
material (mud), then a continuous layer of grass and herbs or shrubs
grows across the swamp with roots barely penetrating the thin, soft layer
of mud so as not to bioturbate the continuity of the thin mud layer, then
all subsequent vegetation grows on top of the first layer of vegetation
with roots entirely above the mineral (mud) substrate.
Kevin, this sequence of events to produce a parting strikes me as a "just
so" story. I'm going to start carrying a pair of waders with me, and the
next time I see a swamp I'm going to wade out into it and pull up some
grass and small trees just to see how shallow the roots really are. I'm
going to bet that the grass, shrub and tree roots all grow down more than
the top millimeter of soil, and well below the water table. I will get
some before and after photos to send you to show where the plants were
growing before being uprooted and then what the roots look like
immediately after being uprooted. I will report what I find, and will
eat crow if you are right. [I love crow :-)]
> I am in charge of reclamation at the closed mines where I work, so I
> know the basics of revegetation (but remember I'm a geologist).
> Whether it is the natural colonization process that we see on
disturbed
> ground, or when we revegetate by planting, the pioneering vegetation is
> always shorter stature plants first (grasses and herbs today) followed
by
> shrubs and trees. This is due to the low nutrient content of the
> bare mineral soil. Once the pioneering vegeation takes hold, leaf
litter
> buildup and nutrient cycling begins. Then it will support larger
vegetation.
I used to work with mine reclamation, and I couldn't disagree with you
more. Have you ever seen a tree growing out of the side of a rock face?
I grant you the weathering products in Alabama may be different than
those at your latitude, but trees grow in rock by forcing their roots
into the cracks and getting what nutrients they can. We usually would
revegetate reclaimed strip mines with pine trees, planted on graded
spoil. If topsoil was available it would be spread in a thin layer over
the spoil, but the topsoil would only be enough for the grass; it would
not help the trees, except possibly by leaching. Lime and other soil
amendments might be broadcast over the reclaimed area prior to planting,
but after the first season the vegetation was on its own. I have heard
strip miners remark that pines grow better in spoil than in the native
soil which had been leached of nutrients over the years. Looking at the
stands of pines after a few years of growth, I can't disagree. The grass
and leaf litter will help retain moisture and possibly contribute
nutrients as well, but I do not see from my experience that trees require
"leaf litter buildup" before they can grow.
In our thin-parting-formed-in-a-swamp scenario, the peat litter would be
only a few mm below the top of the thin mud layer, so the nutrients are
there for trees to immediately tap into. Also, in swamps I have seen,
there is not a layer of leaf litter - you can see mud on the bottom next
to the trees which are usually standing in water. Several web sites
mentioned the saturated soil as being a "muck", with fine roots deeper
than 51 inches. I don't know if the active roots are that deep or if
these were once shallower roots that were buried by sedimentation.
> I think the answer to the question of why there are not more roots
> below coal seams is that the roots we see preserved in the floor rock
are
> those of pioneering plants which grew when the water table was
> relatively low. Once the water table rose, then peat forming plants
> kicked into high gear, and they didn't need to send their roots down
> deep into the floor.
Again, I disagree. If you can support your contention with modern
examples, I'll listen, but remember, "the floor" in an intraseam parting
is a very thin layer of mud, and the roots of the pioneering vegetation
must not disturb the planar top and bottom contacts of the parting while
they establish a carpet of vegetation sufficient to support and contain
the roots of all subsequent generations of vegetation. And I think you
contend that often we don't even see the roots? Are you proposing
floating aquatic plants that provide the initial layer of peat? Careful
how you answer that. :-)
> From the above description, I think the carbonaceous material
> represents flattened vegetation on the top and bottom of the tonstein
and/or
> roots penetrating it. The contact is sharp, except for the graupen in
the
> enclosing rock, so there is no destruction of the layer by roots, as
> you seem to think is certain. As to whether the roots are detrital,
> there is no sure way to tell from this description.
> No. My explanation why there is not intense rooting below every
> parting is above. Your mental picture is that intense rooting is
essential.
> This is an expectation that you have set up. Once you step away
> from this preconception, even temporarily, you will be free to consider
> other explanations.
I think you are trying to demonstrate your point by using descriptions of
strata with roots which you admit may or may not be detrital: "As to
whether the roots are detrital, there is no sure way to tell from this
description." If these roots are detrital as I contend, then you cannot
use this example to demonstrate the lack of bioturbation by in situ
roots. Please present modern examples which are clearly in situ and
which clearly show a lack of bioturbation of planar soil layers.
> No, generally you should be able to see roots or root traces if they
> are there, but in dark lithologies this may not be true.
On the web (Google search "swamp + roots" and "swamp plants")I saw
reference to dark muck, but I doubt that this muck is layered.
> Pioneering vegetation doesn't have a high root density, so I have
> observed that it doesn't bioturbate the underlying sediment much if
> at all.
Are these observations of modern pioneering vegetation? Can you provide
a photo of an undisturbed, layered sediment with pioneering vegetation
sufficient to support all subsequent vegetation? Perhaps we need to set
up a model in an terrarium and see what happens.
> Bill, the above makes our whole debate about the formation of coal
> pretty pointless. You have strong faith which includes taking the
> young earth/flood account from the Bible. That's fine, but with all
due
> respect, bringing this to the table as the starting point, and
> trying to rationalize the data to fit this model, is not something that
I
> would describe as science. You may not believe this when I say it, but
I
> really don't care which model for the formation of coal is closest
> to the real explanation - I will side with the one that is best
> supported by the data. I think if you were to adopt this approach, and
an old
> earth/non global flood explanation was best supported by the data,
> this would conflict with your faith. You would then be faced with
> choices - reject or ignore the old earth/global flood explanation to
keep your
> faith intact (this is entirely your choice and I won't knock it), or
> modify/reject your faith.
No, Kevin. My faith is nonnegotiable. I may modify my interpretation of
Scripture. Tell me where I said my faith includes "taking the young
earth/flood account from the Bible."
> I can't see that you can be objective with the beliefs you bring to
> the debate. An example of this stance is the Statement of Faith of
> Answers in Genesis. The last article reads "By definition, no
apparent,
> perceived or claimed evidence in any field, including history and
> chronology, can be valid if it contradicts the Scriptural record. Of
> primary importance is the fact that evidence is always subject to
> interpretation by fallible people who do not possess all
> information." I think anyone adopting this has stated up front that
they will not
> be objective.
The question is how to interpret the Scriptural record. You and I may
have different interpretations, and we may both be wrong.
> As I have stated before, the degree to which one can be objective is
> the degree to which one can set aside one's preconceptions. I hope
that
> I can set aside some or all of my preconceptions of an old earth to
> consider models of coal formation (maybe some would disagree with me
> on this), but if the belief in a literal reading of Genesis is a
> cornerstone of your faith which you cannot set aside, you cannot be
> objective.
I feel that you are putting words into my mouth. Please quote where I
said "a literal reading of Genesis is a cornerstone of [my] faith which
[I] cannot set aside." I know you prefaced that quote with "if", but the
thrust of this thinking is to leave the "if" out.
> You will need to give more weight to data that you feel
> supports your position, and less weight to data that supports other
> positions; otherwise you will be forced to confront your faith.
> This is not objectivity. It's exactly what is happening in our debate,
and
> is the reason why I said the debate is becoming pointless. You have
> asked many many questions to clarify my points, and I welcome them,
time
> consuming as the research may be. But, you have come up with
> improbable explanations to support your model, i.e. dilution of
seawater by
> torrential rainfall in inland seas to explain low sulphur coals,
> tonstein emplacement beneath floating mats, etc. Can anyone state
> that these explanations are impossible? No, but you have not made a
case
> that they are reasonable and probable. You need to adopt
> improbable explanations because they fit your young earth paradigm.
Let me ask
> you this - do you feel you are considering all the data objectively?
You're asking the wrong question. I am definitely considering all of the
data and offering the best explanations I can come up with at the time.
Are my explanations exhaustive? No. Are there other possible
explanations that I may not have thought of? Absolutely. You're
frustrated because I don't move away from the Flood model. If I followed
you and Glenn I would be shutting doors behind me.
Last night as we ate supper, my wife asked me, "Where are you?" I was
looking down at my food so she couldn't see my face, much less my eyes,
which I told her. She said she could hear the wheels turning. I told
her that I was thinking about Glenn's question from two or three weeks
ago (which I still haven't answered). Our discussion is always running
in the background, and occasionally I will get a fresh insight. In fact,
I had three in the last week.
We live on a small lake. We had some severe weather last week, which
washed a lot of leaves and debris into the lake. As I was driving out a
day or so later, I noticed the debris was concentrated along the
shoreline in the eastern corner of the lake. I remembered our discussion
about floating mats and you saying that they would disperse since there
would be nothing to hold them together. Here was a floating mat that had
been pushed together by the wind. It was still there the next day.
Last week we drilled (augered) and installed a temporary monitoring well
in gray shale. I came back about 4 hours later, grabbed a water sample
and poured it into 3 40-ml vials preserved with HCl. The sample was very
turbid, almost black. I assumed that since the well had been sitting for
several hours and collecting ground water, the sediment that was still in
suspension would remain in suspension during the time I was working with
the sample to get it labeled and packed for shipment. I was surprised to
see that after only a couple of minutes the upper half of the water in
the 40-ml vial was clear. The acid apparently caused flocculation of the
suspended sediment. The sediment was still very fluid. The 40-ml vials
are about a half-inch in diameter and almost 3 inches long, and the
sample fills the bottle, with no air bubbles. I tilted the sample and
watched the turbid sediment flow from the bottom end of the vial under
the clear water, and the clear water flow over the sediment. I realized
that if this had been a shallow-water basin and floating plants with
bare roots had been resting upright on the bottom, then this dark
sediment would have settled around very delicate roots and produced what
appeared to be a rooted soil. The sediment could have also settled out
in a thin, horizontally extensive layer across the bottom of a basin
covered with debris from a floating mat. Since the sediment was of a
single grain size, there would be no Bouma sequence to identify this as a
turbidite.
I knew if I didn't write these down, I would forget one. It'll come to
me later.
> Are other explanations possible? Yes, but I prefer to go with the
explanation
> that seems most probable. Does my personal stance make it
> impossible to be objective? I don't think so, but others might.
I would say neither of us is objective, which is why we need one another
- to point out weaknesses in the other's arguments.
> Turbidites have a specific set of diagnostic characteristics: the
> Bouma sequence. They are from density flows of turbid fluid, diplaying
> graded fining upwards bedding.
Again, if the turbidite entrained a well-sorted (uniform grain size)
sediment then there would be no fining-upwards grading.
> mixing with other sediment would occur. There are many examples of
> "clean" (pure) tonsteins.
An intraseam tonstein is another type of parting. In the water-borne
clastic partings discussed above, you said the water killed the trees to
make the swamp floor flat before the clastic mud was deposited. I think
you said that you don't know of any Canadian tonsteins occurring as
intraseam partings, but I have sent you a CD (that you may not have yet)
with pictures of intraseam tonsteins occurring in Australia - and they
don't contain standing trees or roots. I know you want to finish
discussing the Gates before we move on, but this is a question you will
need to address later: Why do intraseam tonsteins (some at least) not
contain either standing trees or roots from vegetation that
re-established on top of the tonstein.
> >Currents in the open water would disperse the suspended ash
> > over wide areas beneath a floating mat.
>
> Yes, they would disperse it all right - so it would no longer be a
> distinct layer. (Kilby, 1984): "any environment with more than a
> minimum energy level will obliterate ash falls. Thus, tonsteins and
> bentonites preferentially occur in low energy marine and coal swamp
> settings."
Please explain how a tonstein forms in a "coal swamp" with active
bioturbation from plants. Also, please explain how tonsteins form in a
"low energy marine" setting where animals bioturbate the bottom.
> Most of my objections to the floating mat model apply equally to
> non-Cretaceous coals, i.e. the sulphur problem, tonsteins, the
> association of coals with non-marine and shallow marine rocks only.
Tonsteins are harder for you to explain than for me (IMO). Since we
don't know what the rainfall was like during the Flood, then sulfur is
not and insurmountable problem in my mind. Coal is associated with
virtually every type of shallow-water environment we can imagine, meaning
that if the coal was formed in swamps then those plants had a wider range
of environmental tolerance than swamps today do.
> So Bill, is it worth continuing this debate?
For my part it is very worthwhile, and I appreciate your time.
Thanks,
Bill
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Received on Fri Feb 13 00:51:55 2004
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