Please ignore my typos and lapses in sentence structure as well, most all of us make them.
Earlier post continued:
Geode: “You are jumping to a conclusion that the sediments are mostly sand, at least if the report you link is your only source of information. It does not specify this. The darker sediments are of a shade of grey common to shales and there appear to be more massively bedded and lighter sandstone lenses within them.“
I put a question mark on sandstone. Although shale is probably closer to right, since shale is a mixture. The rock has silicates, plant material and charcoal in it. The report said the fill was silicate based if I remember correctly--I suppose to differenciate it from the calcite based limestone.
I believe the important point in terms of origin is that it is a different deposition.
Shale usually is no more a “mixture” than sandstone and shales and sandstones are indeed both silicates. I don't think the report said anything about "silicates" as there would be no reason to do so as this would have been a logically accepted "given" in the lithologic terms used.
Geode: “The limestone above is cited as being dated as Ordovician with the caves eroded in Pennsylvanian times. The dating of the fossils in the clastics infilling the presumed cave is mentioned, and the limestone would have been dated similarly. If you want to take issue with the dating methods, that seems beyond the scope of what we are provided. “
I think it would be safe to say that relative dating by index fossils was the basis of dating, although radiometric dating may have taken place.
Using index fossils assumes they evolved. For instance, ammonites are used as an index of Sulerian and early Devonian period, so the strata are assigned that age no matter their mineral content. If it seems to be out of order, it is conclude to be "reworked." This presupposes the fact that ammonites evolved into and went extinct in a certain time period.
Also, many fossils that are found in one period, are assigned to later also. There is constantly new data coming in. As I have said before, if they ever find a human skeleton with a dinosaur, they either move man back, and /or the species of dino up as a "straggling survivor." The GT will just adjust.
If a live ammonite was found today, they would just call it "a living fossil." While this may be called good science by some, it is called circular reasoning by creationists based on the presupposition that the GT is reality--a worldview.
At any rate, despite the fact that old earthers tell us the ammonites existed some 400 million years ago, there are numerous documented fossils, including ammonites and associated wood, that have 14C levels which calculate into thousands of years--not millions. These datings are done by reputable labs, which are quite capable and substract a given amount for background and contamination.
Yes, it would be imposing a worldview to do as you claim. However, I have heard this reasoning about dating many times before and I think it is generally false. Sorry, I don’t buy into this “conspiracy theory” of how dating is done by workers in science, for one thing because I have been involved is some biostratigraphic work myself where all the fossil forms did not appear to make sense in the places they were found. We re-sampled to verify what we had found and in doing so determine why fossils that seemingly did not fit were in our samples. We found contamination coming from caved material from above. This was also verified by the lithologies in which the fossils were found. I hear this argument quite often on boards such as this one and in my opinion it is not the practice of geologists and paleontologists to do this. It would be intellectually dishonest and unethical in my opinion. Technical papers in geology commonly have a discussion of age dates that do not fit that is far more objective than you have implied. Sometimes the researchers simply state that they do not know how to reconcile all the data.
Biostratigraphy is most often done by using “range zonation”, as what you have noted is correct about the occurrence of fossils through more than one interval of time. Re-working sometimes occurs, but typically physical evidence such as erosion of the fossil’s surface has already caused suspicion that this is the case right from the start. Some studies are flawed, but not to the extent that is implied here, or using the bad scientific methods that you imply. The dating methods used are not circular but that has been explained in other threads and I know that dedicated creationists do not accept the reasoning. involved. I think it is because of the worldview held that anything that does not fit into the preconceived model of The Flood cannot be correct and therefore is rejected out of hand. I guess they assume that anyone on the other side will approach evidence in the same manner but this is not the case. It has been widely claimed that the ICR has a statement of faith that all must sign that basically says that anything that does not fit into the literal interpretation of creation as they have interpreted it from the Bible must be automatically rejected as false. Mainstream science does not follow this sort of worldview if done properly. But at least the standard is to uphold objective research.
But this is off on a tangent, for the fact is that human skeletons have not been found with dinosaurs and ammonites have not been found living today.
I think a discussion of radiometric age dates is irrelevant to what we have been discussing and will just take the thread away from what actually is in the report. But since creationists tend to say that such age dates are flawed by definition, why cite anything about them at all? It sort of strikes me as the author of he reference you give is saying “we will believe the data when it conforms to what we already believe and reject it when it does not.” In my opinion the vast body of evidence is to the contrary, with good substantiation of dates obtained by collaborative studies using similar and different means. A few age dates appear wrong from time to time, that is the nature of such detailed work when proper methods are not used. But at other times they have been correct and the assumptions previously being made have to be altered. But the way creationists tend to approach radiometric dating seems to be in essence doing what you seem to be claiming paleontologists do with some of their data. Reputable labs can only make the best of what they are given. I have seen discussions where the methods in which the samples used by Snelling and others have been obtained has been cast into considerable doubt, If correct, the conclusions reached have little or no meaning.
Geode: “Your conclusion that burning wood got buried underwater as indicated by the presence of the limestone mostly certainly is not supported by what is reported,”
I gave a hypothesis--not a conclusion. A possible flood geology scenario is not a conclusion. However, scientifically, one can say (independent of the overlying limestone) by the fact of charcoal in the underlying sediment--it was deposited rapidly. Burning wood has to be buried to make charcoal--an empirical fact that I saw in Africa when I was a missionary.
So the wood was still burning when buried. No opinion about that.
Secondly, the deposition was a slurry--sediment mixed in water. Nothing else but water will move that sediment--unless you believe landslides somehow filled the cave to the brim--which I find highly unlikely--especially given the geology of northern IL.
Rapid deposition plus water means there was a rapid current involved. In other words, the slurry had to pick up the burning wood and deposit it before it extinguished.
OK, I find fault in your hypothesis. I think it is distinctly your opinion that the wood was still burning when buried. This may have been true for some of it but not likely for all, or even most of it. Why does having charcoal in the sediment indicate rapid deposition?
Yes, I agree that charcoal is created when wood is heated in a relative absence of oxygen but this does not have to occur with burial. There isn't much oxygen in some parts of a forest when it is in full blaze. Despite the use of the term "burning" in the report, I think you originally used a better term "pyrolysis" for the creation of charcoal. I have walked through areas that have been consumed by forest fires and considerable charcoal was left behind, principally in charred tree trucks.
Where was a “slurry” mentioned? I don’t think I would apply it here as it usually implies very fine grained material and viscosity not generally present in sediment deposition by water. It indicates sediment being carried almost entirely in suspension. I was not the one to bring up landslides. I accepted the report's claim of deposition by water.
Geode: “We don't know that a "gradualist" conclusion was reached or is an assumption that was been made in any subsequent study. Personally from the description of the sediments I would guess that part, or all were the sediment was deposited relatively rapidly. “
The origin of the limestone is dogmatically gradualist in any geological circle--whether it be professional, educational, or the press. There will be no compromise of this, and actualists will hold this gradualist stronghold. The geologic time periods are gradualist deep time. So what you have earlier preposed to be possible shale can be deposited rapidly you say, but you will not say that about the limestone.
Ancient lime mud found in limestone matrix is not like modern lime mud, either in it's crystal type (calcite and arogonite respectively) or grain size (much smaller than modern). Why? You have to create a hypothesis on this one, and it will blend with your personal worldview.
Once again, I don’t approach geology consciously from a worldview as you imply, except that I feel natural laws are valid and that the best approach to doing scientific work is to assume that the laws are operative. I don’t think, “In what part of the Great Flood did this occur?” Or how does the vast length of earth history impact this.” I have approached carbonate petrology looking at the data and then asking myself what it is telling me. I have studied both ancient and modern lime muds. Actually there is quite a problem in deciding even what a "lime mud" is in terms of grain size. That was a problem with Bob Folk's original classification of "micrite"...he placed the grain size limit lower than many geologists felt comfortable with using. So I think there is a problem with the pigeon-holing that comes with classification schemes and possibly somebody has been twisting definitions in the source that you got this information from in order to make a point that is probably quite incorrect in some ways, probably due to force-fitting it into a worldview.
It has been generally observed that aragonite is deposited more commonly and in larger proportions in the primary deposition of a very fine-grained carbonate rock. But carbonates are trickier than clastics in that they re-crystallize in later stages of the rocks cycle. The crystal structure present after the deposition of ancient muds is likely to have generally been the same as in modern muds as is the grain size. Yes, some ancient limestones are finer-grained than modern ones that form under similar conditions. This is due in part to diagenetic changes that alter grain sizes. Diagenesis is typical in carbonate rocks. When thin-section petrographic analysis of pre-Pleistocene carbonates is done the outlines of what were aragonite grains can be seen. I have seen this myself in my own thin-sections. Aragonite is relatively unstable compared with calcite and the outlines of original aragonite skeletal fragments can be seen where a mold or void has been filled with smaller crystals of calcite.
There was absolutely nothing mentioned about the rate of deposition of the limestone in the report, which was the point I was making. You have interjected an idea not present in the report. I also don't think concepts of carbonate deposition are as dogmatically gradualist as you claim. There have been instances noted of carbonate deposition that have been termed “rapid” and taking place at similar rates to terrigenous sediment deposition. Of course if you insist that hundreds of meters of limestone can be deposited in a year that would be deposition on at an “astronomical” rate, not on that is simply rapid.
Geode: "Many depositions"...? Again, I can't tell from what is written here what was thought to be the case. Millions of years to infill the cave? That would be very unlikely in my opinion amd no claim of such is noted in the report."
I just read a paper last month on the scablands, where the argument of multiple flooding is "supported" by the fact of the multiple strata in certain canyons. To say that multiple strata aren't considered multiple depositions is not evidenced in the writings and speech of geologists.
Obviously some strata are the result of different depositional events than others in a sequence. But no, I do not agree that all strata are the result of different depositional events. How about the result in the experiment in the video "Drama in the Rocks"....? How many "depositions" were involved? I would say that one continuous depositional event was shown that created multiple “layers” or “strata” that were identified by the people who set up the experiment and recorded the deposition for all of us to witness. Often paraconformities will be present between bedding planes but not always.
But my point was that the report said nothing about any of this. In my opinion I would guess that multiple depositional events were in fact involved in filling in the cave, but this is my making an assumption outside of what was reported.
Geode: "No catastrophe is necessarily indicated unless any forest fire qualifies as such."
Then what other possibility do you include? There is transported sediment and transported burning wood being deposited, and the wood is still burning under the sediment when deposited. This is evidenced by charcoal fragments.
One thing is sure. A time limit is on the transport and depostion of the burning wood. What other mechanism can provide rapid transport of these materials except catastrophe?
I think it was implicit in what I wrote that I accept that forest fires are the likely cause of the formation of charcoal. Just about every forest fire creates charcoal. Are all of them catastrophes? I would say that many are not considered as such, and “controlled burns” are even purposely set. I have walked through open areas that had been burned weeks or months before and charcoal was always present. I have seen charcoal in places that were burned years before. Charcoal is found in other deposits that are not associated with caves, in rocks of various ages.
One again I reject the notion that "burning wood" was being transported. I think charcoal was created in events separate to the transportation and the final deposition. What you are saying was not in the report but apparently cut from the whole cloth of your worldview. It is not supported by what is physically seen in our environment. Fire and water do not co-exist as you are implying. Forest fires are doused by water being dumped on them, sometimes more effectively than at other times, but burning wood is not transported away. A rainstorm will put out a forest fire. Some materials can burn underwater, but wood is not one of them. The formation of the charcoal would clearly have taken place before it was transported.
Try placing the burning charcoal from your BBQ into a swimming pool and see how long the burning continues....burning wood would be transported probably only a few feet before at the most before it was no longer burning. It never would have reached the cave. So no, I don't see the time limit on the transportation and deposition of the charcoal to be all that limited or short. I have seen charcoal that had been created in a forest fire years earlier. Charcoal is a relatively stable substance that does not rapidly decay.
What else could account for what is found in the sediments? As the report indicates dry conditions could have caused forests to be more susceptible to fires. I suppose an even greater amount than usual could be created where an accumulation of logs on top of each other provided such a state where oxygen was more likely to be excluded and more charcoal was formed. A lightning strike could light them. A greater amount of charcoal would be created in the lower layers of logs. Flash floods could then move the charcoal towards the mouth of the cave or through sinkholes where it was deposited with other sediment carried by the flood waters. This could be something that was repeated multiple times. I see no need to invoke a catastrophic event. Of course any fire that destroys life and property today is considered catastrophic, but in regards to the deposits noted in the report I don’t feel the creation and transportation of the charcoal required anything that we do not now see taking place on the planet every year.
Time is not permitting me to continue. I do thank you for your comments. As far as the nodule shaped formations on top of the central deposition. Whether you want to call them intrusions or whatever else--they intrude into the overlying layers. I find it difficult to believe the entire deposit fills the entire cave with no gaps--but rather with these intrusions included! How would sediment do this even if there were concave "holes" in the above limestone? It would either have a fissure or point of entry in the top of the "holes", defy gravity, or it is a result of superpositioning of the limestone.
Thanks you for posting the interesting report. I have not worked with karst geology in a long, long time and it was interesting to see this new development.
You know the saying, "Nature abhors a vacuum"...it generally applies to "gaps" in the subsurface as well. If you had land with gopher holes and the land became covered by a river carrying sediment, do you think any holes or tunnels would remain open, or would they fill with water and sediment? If a slurry was really present as in your hypothesis any water would carry quite a bit of sediment load.
An intrusion would have to "intrude" as you have said. We are told nothing about the upper contact of the clastic sediments with the limestone. It is a pity we cannot simply walk to the outcrop and look. If the limestone had been soft you would see deformation around any such "intrusive" feature. I can see none, although it is hard to evaluate from the photo.
The ceilings of caves are sometimes irregular and filling in such a pre-existing shape could account for what appears to be an intrusion to you. The ceilings might have become more irregular when waters started flowing within them. If we take Steven Austin's conclusions to be correct the cave's shape could have been altered quite a bit in a short time. Dissolving something the size of what we see here could have been effected in a short time (by his calculations) even as sediment was deposited on the floor of the cave. There were probably also the effects of gravity in filling the cave, and the slope of the cave may have been significant. The sediment could "backfill" until the the entire cave was completely occupied by sediments. The uncompacted sediments would still have a lot of porosity and water could continue passing through them. Sort of like coffee grounds through a filter the sediments could be stopped as the water continues to drain. The sediments would sequentially build up until in contact with the ceiling. No need to defy gravity.