In Re: Creation Ex Nihilio and other journals
On Date: Tue Jan 09 2001 - 00:22:51 EST
Jonathan Clarke (jdac@alphalink.com.au) wrote:
>(Bill Payne wrote:)
>>On Sat, 06 Jan 2001 22:38:59 +1100 Jonathan Clarke
... text deleted ...
>>I did my graduate work at the University of Tennessee
>>and mapped a quad which included the Knox Dolomite
>>at the base of the section, and a number of other
>>carbonates above the Knox. Although I wasn't looking
>>for karst at the contacts, it is my general recollection
>>that the only karst I saw was on the outcrops which had
>>weathered for years. I do know that there are plenty of
>>carbonate formations here in Birmingham and north in
>>Alabama which display planar bedding and a planar
>contact with overlying formations. In fact, I don't
>>recall ever having seen any karst weathering except
>>at the ground surface or in caves.
>These features can be subtle in cross section. Mussman
>et al. noted that that the Knox surface is a was in some
>places a disconformity, missing only a few m The
>equivalent post-Romaine surface in Quebec is extremely
>planar for the most part. However, it still shows features
>of subaerial dissolution, as described by Desrochers and
>James.
If the coastal plain was flat and of very low relief,
it is unlikely that any sort deep karst would develop.
Such coastal plains would create contacts of such low
relief it would be very difficult to detect this relief
in single outcrops without very detailed work. Their
buried surface, especially if partially or completely
strip by shoreface erosion during a transgression
would look like and often be a very planar contact.
However, the original discussion was neither about whether
karst weathering occurs in the limited areas that Mr.
Payne has studied nor about disconformities associated
with the Jeffersonville, Louisville, and Pegram limestones.
By focusing on theses narrow examples, a person readily
overlooks the fact that major paleokarst of Paleozoic
and Mesozoic age does exist. This is the mistake that Young
Earth creationists makes when they focus the paraconformity
between the Redwall and Muav limestones. As a result, they
completely ignore the spectacular paleokarst that developed
within the top of the Redwall Limestone during the
Paleozoic. Some information about is can be found on-line
in "Paleoclimate during the Redwall karst event, Grand
Canyon National Park" at:
http://www2.nature.nps.gov/parksci/vol18(1)/12kenny.htm
At that web page, Kenny states:
"During the time the Redwall Formation was exposed
to the atmosphere (subaerially exposed), the limestone
was severely altered by chemical dissolution and
reprecipitation and developed a recognizable karst
(limestone) topography replete with caves, caverns,
sinkholes, chert-lag breccias, red-residual soil, and
related solution features."
"During the Redwall karst event, chemical dissolution
of the chert-rich limestone produced numerous large-
and small-scale features. In many areas of northern
Arizona (outside and south of Grand Canyon National
Park), much of the limestone was completely dissolved
away, leaving behind a heap of more chemically
resistant, partially weathered, and cemented chert
breccias or "lag" deposits. In some areas, these
residual chert-lag deposits are quite extensively
developed (fig. 3)."
Detailed information can be found in Kenny (1989).
I realize that Mr. Clarke presented a number of other
examples of paleokarst in his previous post. However,
I cannot resist this example from the Ordovician of
Texas. About it, Hammes et al. (1997) state:
"Karst-related processes were of fundamental importance
in the development of Lower Ordovician Ellenburgeral
exposure during the post-Sauk unconformity, extended
as much as 1,000 ft below the top of the Ellenburger
Formation. Typically, two main levels of brecciation,
which are related to cave formation, are recognized in
>1,000-ft-long cores from the Val Verde and Delaware
Basins. The upper level is characterized by a distinct
tripartite division of breccias and clastic cave-fill
deposits. The lower level typically is composed of
stacked fracture and chaotic breccias but contains no
clastic cave fill. The different breccia levels are
separated by undisturbed shallow subtidal to intertidal
facies and occasional thin brecciated intervals. The
Ellenburger caves and breccias formed as a result of
a multilevel cave system that developed within the
vast Ellenburger carbonate platform. Vadose processes
contributed karst features close to the unconformity,
whereas phreatic and water-table processes formed an
extensive, multilevel karst system as deep as 1,000 ft
below the pre-Simpson unconformity."
After reading this abstract, I have to conclude that
either Hammes et al. (1997) or Emil Silvestru deserve
to recognized as an accomplished master(s) in the field
of science fiction writing. One or the other is selling
reale estate in twilight zone as science. (In fact, I
heard a rumor that a fellow geologist has requested a
copy by interlibrary loan of the paper by Emil Silvestru
so he can write a review at the request of the National
Center for Science Education Reports. The results should
be interesting.)
>>On page 208 of _The Genesis Flood_ by Whitcomb and
>>Morris, there is a photo of Jeffersonville Limestone
>>(lower Middle Devonian age) overlying Louisville
>>Limestone (Middle Silurian age). The photo caption
>>says: Figure 23. A "Deceptive Conformity," or
>>Paraconformity. This is a typical example of an extremely
>>common, yet quite paradoxical, phenomenon, namely the
>>perfectly conformable superposition of a younger
>>bed upon a much older bed, with many intervening
>>geological ages entirely missing. The Jeffersonville
>>limestone, of lower Middle Devonian age, is here
>>resting quite normally upon the Louisville limestone,
>>of Middle Silurian age. The significant thing is that
>>these formations are separated by more than 3000 feet
>>of strata in other parts of the Appalachian trough,
>>and therefore it must be assumed that many millions
>>of years elapsed between them, although they look as
>>though they must have been laid out in quick succession.
>>This phenomenon has been variously called a
>>"disconformity," a "deceptive conformity," and, more
>>recently, by C. O. Dunbar and John Rodgers, a
>>"paraconformity." (Principles of Stratigraphy, New
>>York, Wiley, 1957, p. 119).
Just because strata "look as though they must have been
laid out in quick succession" does not mean that they
have been. The problem here is that Whitcomb and Morris
(1961) fails to present enough information for us to
know whether that this is actually the case or they are
just mindlessly waving their arms about in speculation.
All they provide is a distant photograph of the outcrop
and an ancient quote about a "deceptive conformity" based
on decades old publications. Neither of these items serve
prove that a problem exists.
The difference in thickness is nothing mysterious. This
can reflect simply lesser amount of accommodation space
for sediment to accumulate in the area of the outcrop
as the result or substantially less subsidence or stable
nonsubsiding craton. For an explanation of accommodation
space, go read:
LECTURE 6 P Facies architecture in shallow marine systems
http://www.bdrg.esci.keele.ac.uk/Teaching/304/lectures/l6.htm
http://www.bdrg.esci.keele.ac.uk/Teaching/304/lectures/l2.htm
>>Also, on page 210 of _The Genesis Flood_ is "Figure
>>24. Double Paraconformity." The caption says: In this
>>Tennessee quarry are exposed two major paraconformities,
>>above and below the Pegram limestone, which is lower
>>Middle Devonian. The Chattanooga shale above is upper
>>Devonian and the Lego limestone below is Middle
>>Silurian. Again there is no physical indication
>>whatever of any substantial time lapse between the
>>deposition of these various strata.
Again the documentation on this outcrop is sorely
lacking any of the data needed to make any sort of
comment about it. Whitcomb and Morris (1961) again
presents a distant photograph of an outcrop, a few
stratigraphic names, and nothing in the way of any
descriptions of the stratigraphic units in terms of
their lithology and stratigraphy. Also Whitcomb and
Morris (1961) provide no explanation for the
statement "...no physical indication whatever of any
substantial time lapse between the deposition of
these various strata." A person is left to wonder
if this statement is based either on their imagination,
wishful thinking, divine inspiration, inspection of
the outcrop, a geologist they talked to, something
they read, or a dream that Morris had the night
before he wrote the caption. Here we have more YE
creationist text-bites lacking any supporting data
to back them up.
>>Do you have any explanation for the _lack_ of karst
>>weathering in the formations described above?
People who happen to be familiar with the geology of
the region might have a clue to what the details of
the geology of the above outcrops. However, the vast
majority of people are going to totally clueless about
character of these units and unable to discuss this
question simply because Whitcomb and Morris (1961) fails
to provide sufficient background information, including
citations, about these outcrops. The question by Mr.
Payne is based on the incorrect premise that the
formations are "described above", which they are not.
This is like me telling Mr. Payne that the interbedded
sandstones and shales, from top to bottom, of the
Sharps Formation, Brule Formation, Chadron Formation,
Fox Hills Formation, and Pierre Shale can be found
exposed in Pinnacles Area of Badlands National Park
can be found; posting a photograph to the Internet
and asking him "Do you have any explanation for the
lack of deposits that can be related to the Noachian
Flood the fossil-bearing formations described above?"
Unlike the outcrops that Mr. Paynes asks about, a
person can actually find sufficient descriptions in
the literature to discuss my question.
>I did a quick search using Georf and material in
>the AGSO library, but uncovered little that dealt
>with the contact relationships of these units.
>The exception was one paper which did mention that
>there was quite significant relief along the
>contact Jefferson and Lousiville Limestones, but
>did not clarify whether this was depositional
>relief (the Louisville contains numerous reefs),
>post depositional erosion, or some combination of
>these. However the contract regionally is not as
>planar as the photos in Whitcomb and Morris
>would suggest.
In sharp contrast the vague data provided, e.g. Whitcomb
and Morris (1961), Ettensohn et al. (1988) provide
a marvelously detailed papers with detailed descriptions
and illustration of schematic sections, descriptions and
illustrations of petrogrphic thin sections, comparisons
to modern analogues, and a wealth of other data. They
show in Figure 9 photographs of very similar parallel
bedded limestones with no apparent evidence of sinkholes,
caves, or other obvious karst features. In this case,
although large-scale karst features are lacking, the
limestones themselves show abundant evidence of subaerial
exposure. The evidence consists of beautifully well-
defined alteration of the upper parts of the limestones
by the development of fossil soils. In most cases, such
alteration would be apparent in the distant photographs
and vague lithologic descriptions provided by Whitcomb
and Morris (1961). In the Mississippian limestones
discussed by Ettensohn et al. (1988), the Cave Branch,
Mill Knob, Warix Run, Ste. Genevieve, and St. Louis
Members of the Slade Formation, the fossil soils exhibit
some combination of well-preserved soil structure, root
molds, calcrete, caliche pseudo-anticlines, solution
breccias, sascab, and terra rosa. From Ettensohn et al.
(1988), it is well-documented that thin carbonate beds
can exposed subaerially for thousands, even millions of
years, and still not develop obvious karst features that
can be seen in photographs like those illustrated by
Whitcomb and Morris (1961).
Because Whitcomb and Morris (1961), fail to describe both
outcrops in any detail it is impossible to judge whether
that is actually the case at this time and formulate
any supportable answer to his question. Depending on the
composition of the limestones and shales; their internal
structure; and their regional stratigraphy, the
para- and disconformities might also be explainable by
as being either ravinement surfaces or by the formation
of marine hardgrounds. There exists an embarrassment of
ways about which the lack of karst can be explained given
the utter lack of information that Whitcomb and Morris
(1961) provide about these outcrops.
For "ravinement surface" see:
LECTURE 2 P Sequence stratigraphy: Concepts principles and terminology
http://www.bdrg.esci.keele.ac.uk/Teaching/304/lectures/l2.htm
>I should mention that there are also a number of other
>erosional processes other than karst that effect
>limestones. We should not expect to find evidence of
>karst along every limestone contact, although one
>should look for it, as its presence is very important
>from understanding ancient environments
>and for petroleum prospectivity.
Not only petroleum, but also metallic ores. For
example, do not forget the Paleozoic ore bodies of the
Pine district of Canada and the east and central
Tennessee zinc districts. These metallic ores are
all hosted by karst collapse breccias. These are
discussed in detail by Kyle (1983). Mesozoic karst
containing lead-zinc deposits of Triassic age in Austria
are described by Bechstadt and Dohler-Hirner (1983).
References Cited:
Bechstadt, T., and B. Dohler-Hirner (1983) Lead-zinc
deposits of Bleiberg-Kreuth, In P. A. Scholle, D. G.
Debout, and C. H. Moore, eds., pp. 55-63, Carbonate
Depositional Environments. American Association of
Petroleum Geologists Memoir no. 33, . American
Association of Petroleum Geologists, Tulsa, Oklahoma
Ettenson, F. C., G. R. Dever, and J. S. Grow (1988) A
paleosol interpretation for profiles exhibiting subaerial
exposure "crusts" from the Mississippian of the Appalachian
Basin. In J. Reinhart and W. R. Sigleo
Kenny, R., 1989. Variation in carbon and oxygen geochemistry and
petrography of the Mississippian Redwall Formation, north-central
Arizona: implications for extricating the diagenetic history of
paleokarst carbonates and evidence for the earliest Microcodium
microfossils. Pages 16-18 in Cave Research Foundation Annual
Report 1989. Cave Books, St. Louis, Missouri
Kyle, J. R. (1983) Economic Aspects of Subaerial Carbonates.
In P. A. Scholle, D. G. Debout, and C. H. Moore, eds., pp.
73-92, Carbonate Depositional Environments. American Association
of Petroleum Geologists Memoir no. 33, . American Association
of Petroleum Geologists, Tulsa, Oklahoma
Mussman, W. J., I. P. Montanez, and J. F. Read (1988)
Ordovician Knox paleokarst unconformity, Appalachians.
In: Paleokarst, N. P. James and P. W. Choquette, eds.,
pp. 211-228. Springer-Verlag. New York, New York.
Hammes, U., C. Kerans, and F. J. Lucia (1997) Development
of a multiphase cave system; Ellenburger Formation, Lower
Ordovician, West Texas, Annual Meeting Abstracts, American
Association of Petroleum Geologists and Society of Economic
Paleontologists and Mineralogists. vol. 6:47.
Whitcomb, John C. and Henry M. Morris, 1961. The Genesis
Flood, Philadelphia: Presbyterian and Reformed Publishing
Yours Sincerely,
Keith Littleton
New Orleans, LA
Miscellaneous Web Pages:
Unconformities, Paleokarst, and Tectonic Activity Associated
with the Silurian Lockport Dolomite, Western Ohio
http://www.dnr.state.oh.us/odnr/geo_survey/aapg/abstract/kahle.htm
The Knox Unconformity, and The Arvonia, Carolina Slate
and Other Volcanic Arcs and Terranes Early Ordovician;
500 - 450 mya
http://geollab.jmu.edu/vageol/vahist/G-Ealyo.html
An interesting article can be found at:
http://www.gcssepm.org/cuffey01.html and
http://www.nogs.org/ev_vs_cr.html
Clifford A. Cuffey has another article at:
http://www.gcssepm.org/cuffey02.html
http://www.nogs.org/cuffeyart.html
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