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Author | Topic: Limestone Layers and the Flood | |||||||||||||||||||||||||||
Christian Member (Idle past 6284 days) Posts: 157 Joined: |
Percy writes:
Since magnesium is so common, why is it that dolomite isn't being formed today?
The answer for Christian is that magnesium is a very common element on both land and sea. It is so common that some highway departments use magnesium chloride as a substitute for sodium chloride (ordinary salt) which can contaminate water tables.
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Coragyps Member (Idle past 763 days) Posts: 5553 From: Snyder, Texas, USA Joined: |
why is it that dolomite isn't being formed today?
It is - it's just not very dramatic. I'd imagine there's some forming in, say, Michigan this very minute. There's lots of limestone, and there's grounwater that would pick up a little magnesium from near-surface soil and rocks. All these geological processes are SLOW! We humans have a hard time just with thousands of years. Geology has no problem at all with millions.
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Percy Member Posts: 22504 From: New Hampshire Joined: Member Rating: 4.9 |
Christian writes: Since magnesium is so common, why is it that dolomite isn't being formed today? One of the key principles of geology is that the same processes we see happening today have been happening throughout much of earth's history. The answer to your question is that dolomite *is* being formed today. Very slowly. The principle I mentioned above was in its early days summarized as the present is the key to the past. As a general principle this has been highly successful, but we're also aware of exceptions. For example, we're pretty sure pollution from automobiles is an exclusively modern phenomena. Asteroid strikes have not occurred during recorded human history, but we're very certain they have happened in the past and will happen again in the future. But in general the principle that the present is the key to the past has proved extremely successful. The same processes we see at work on the landscape today have been working on landscapes since the earth first formed. Science is a huge field, so huge that no one person can hope to know more than a tiny portion in any detail. Scientists make advances by building on what came before, not by duplicating what came before. You have a different goal, though, which is to demonstrate to your own satisfaction that what scientists are telling you is actually true. You'll only be able to do this for a tiny, tiny portion of scientific knowledge. You're only one person, and you only have so much time. I think it would be better if you set some kind of threshold for what information you're willing to trust from scientists. Question conclusions on topics on which there is actual scientific disagreement, like global warming or whether we should resume investing in nuclear power. But when every scientific source is in agreement, such as about the organic origin of most sedimentary limestone, then it would be best to move on and spend your time and effort on things more open to question. --Percy
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Christian Member (Idle past 6284 days) Posts: 157 Joined: |
Percy writes: ...But when every scientific source is in agreement, such as about the organic origin of most sedimentary limestone, then it would be best to move on and spend your time and effort on things more open to question. If I could agree with you that EVERY scientific source were in agreement about this, then perhaps I would do that. You have to understand that my Bible says things like this:
quote:If I were going to accept someone's word, I would be more likely to accept Walt Brown's word, than the geologists who have a different world view than I do. You guys are telling me that Walt Brown is wrong. I need to know WHY he's wrong.
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Christian Member (Idle past 6284 days) Posts: 157 Joined: |
Coragyps writes:
But geologists do have a problem with dolomite: All these geological processes are SLOW! We humans have a hard time just with thousands of years. Geology has no problem at all with millions. Dolomite - Wikipedia
There is significant uncertainty regarding the cause of dolomite formation. Vast deposits are present in the geological record, but the mineral is relatively rare in modern environments. This is referred to as the "Dolomite Problem". Dolomite accounts for about 10% of all sedimentary rock, including much that would have been produced near the surface of the Earth. However, laboratory synthesis of undisputed dolomite has been carried out only at temperatures of greater than 100 degrees Celsius, conditions typical of burial in sedimentary basins - even though much dolomite in the rock record appears to have formed in low-temperature conditions. http://mineral.galleries.com/...rbonat/dolomite/dolomite.htm
Disputes have arisen as to how these dolomite beds formed and the debate has been called the "Dolomite Problem". Dolomite at present time, does not form on the surface of the earth; yet massive layers of dolomite can be found in ancient rocks. That is quite a problem for sedimentologists who see sandstones, shales and limestones formed today almost before their eyes. Why no dolomite? Page not found - Jerusalem Stone - Imported Natural Stone
Mixing of meteoric water and seawater has been suggested for dolomitization by Badiozarnani (1973). He indicates the mixing of proper proportions of the two fluids can generate a nixed fluid which is undersaturated with respect to calcite and supersaturated with respect to dolomite. Although evidence of this model has been found in Jamaica (Land 1977), it is generally not accepted as an explanation for the massive dolomites (Sibley et al. 1994). Evidence for the occurrence of dolomitization by normal seawater was found at the Enewetak atoll (Sailer 1984). Whether the minor amounts of dolomite found in deep sea sediments is the result of dolomitization by normal seawater has not been determined.
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roxrkool Member (Idle past 1017 days) Posts: 1497 From: Nevada Joined: |
Dolomite has indeed been a problem for geologists from quite some time, but here are some recent findings regarding the 'dolomite problem:'
ABSTRACT We report low-temperature microbial precipitation of dolomite in dilute natural waters from both field and laboratory experiments. In a freshwater aquifer, microorganisms colonize basalt and nucleate nonstoichiometric dolomite on cell walls. In the laboratory, ordered dolomite formed at near-equilibrium conditions from groundwater with molar Mg:Ca ratios of <1; dolomite was absent in sterile experiments. Geochemical and microbiological data suggest that methanogens are the dominant metabolic guild in this system and are integral to dolomite precipitation. We hypothesize that the attached microbial consortium reacts with the basalt surface, releasing Mg and Ca into solution, which drives dolomite precipitation via nucleation on the cell wall. These findings provide insight into the long-standing dolomite problem and suggest a fundamental role for microbial processes in the formation of dolomite across a wide range of environmental conditions. citation: Roberts, Jennifer A, Bennett, Philip C, Gonzalez, Luis A, Macpherson, G L, Milliken, Kitty L, 2004, Microbial precipitation of dolomite in methanogenic groundwater, Geology, vol.32, no.4, pp.277-280. and
ABSTRACT The failure to precipitate dolomite experimentally at low temperatures or from seawater in which it is both supersaturated and the most thermodynamically favoured carbonate phase, together with its unequal distribution through geological time relative to limestone, are all aspects of the "dolomite problem", a subject of continuing controversy. A plethora of physicochemical models has been invoked to explain sedimentary dolomite formation, none of which satisfactorily addresses the basic problem of how kinetic barriers are overcome. These barriers are related to the disproportionate distribution of the component ions of dolomite, cation hydration and ion complexing in seawater. Competing claims for the effectiveness of sulphate as an inhibitor to dolomite formation further confuse the debate, although there are many reports of modern dolomite associated with bacterial sulphate reduction. The uppermost sediments in some lakes of the Coorong region of South Australia comprise almost 100% dolomite, and afford an ideal opportunity to study this association. Samples of lake waters taken during late evaporative stages of several shallow hypersaline dolomitic lakes showed high initial sulphate concentrations, high pH and high carbonate alkalinities. Pore waters from unlithified lake sediment cores directly below the lake-water sample sites showed a substantial and progressive decrease in sulphate concentrations with depth, coupled with an exponential increase in carbonate concentrations, through the sulphate-reduction zone. By the end of the evaporative cycle, sulphate was entirely removed. High bacterial counts on cultures from the sediment cores, and sulphur isotope values consistent with "bacterial" fractionation in lake waters, indicate that the chemical changes in ambient water chemistry can be related to active bacterial sulphate reduction. Laboratory experiments using sulphate reducers cultured from the lake sediments and simulating the anoxic microbiogeochemical environment of the lakes, have resulted in the precipitation of dolomite, demonstrating that bacterial sulphate reduction in the Coorong lakes modifies lake-water and pore-water chemistry so that dolomite precipitation is kinetically favoured. Given the wide spatial and temporal distribution of sulphate-reducing bacteria, and their frequent association, both past and present, with cyanobacteria, it is likely that this process was more widespread in the geological past when dolomite was found in far greater abundance than limestone. Bacterial sulphate reduction may thus have played an important role in dolomite formation throughout the geological record. citation: Wright, David T, Wacey, David, 2004, Sedimentary dolomite; a reality check, Monograph: The geometry and petrogenesis of dolomite hydrocarbon reservoirs, Geological Society Special Publications, vol.235, pp.65-74. Sulfate-reducing bacteria seem to be a front-runner in the production of dolomite. Changes in seawater chemistry through time have probably made it impossible or difficult for SRB to force dolomite precipitation, but apparently this is not the case in some hypersaline and freshwater lakes. These findings still do not rule out the possibility of dolomite replacement of calcite, however.
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Percy Member Posts: 22504 From: New Hampshire Joined: Member Rating: 4.9 |
Christian writes: If I could agree with you that EVERY scientific source were in agreement about this, then perhaps I would do that. You have to understand that my Bible says things like this:
quote: What has this to do with limestone layers, or with science at all? When you read in the newspaper about the latest scientific advance, say the latest unmanned mission to Mars or a new development in gene therapy, do you really think about Matthew 7:13? The Bible has nothing to say about limestone layers, and it isn't a science book. Your skeptical stance about limestone has nothing to do with scientific validity and everything to do with whether or not you think you see a conflict with your beliefs.
Christian writes: You guys are telling me that Walt Brown is wrong. I need to know WHY he's wrong. Why Walt Brown is wrong is simple: he's not doing science. What he's doing is creating fanciful scenarios and passing them off as science to the credulous. The next question should be, "How does one tell the difference between someone doing science and someone creating fanciful scenarios?" That's a tough question to answer because the answer is different for every individual. It's a function of how much you already know. If I explained quantum entanglement to you and told that it makes faster-than-light communication possible, I expect I could convince you. But most of the evolutionists here know enough quantum theory to reject the notion out-of-hand. Faster-than-light communication is ruled out as we currently understand things. The more you know the better you'll get at separating the wheat from the chaff, the gems from the flim-flam. But it isn't necessary to do things like personally seek out limestone and conduct your own investigations, not because it isn't a good idea, but because it would take forever to acquire any meaningful amount of scientific knowledge. As an exercise to become acquainted with scientific approaches to acquiring knowledge, carrying out some investigations yourself is a great idea. But only accepting that which you have personally verified will limit the amount of knowledge you can acquire to a pittance. --Percy
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jar Member (Idle past 423 days) Posts: 34026 From: Texas!! Joined: |
Let me insert a quiet word here if I may on the nature of problems.
There are lots of "Problems" in all sciences. What this means is either that there is no answer right now that satisfies all the conditions, or there are multiple answers and one or even all of them may be correct. But a "Problem" is not a problem! Problems are the frontiers, they are the places where once we do understand what's happening, we will gain a whole new insight into our universe. One thing a "Problem" never is. It is NEVER a place to just stop looking and stick in goddidit. Aslan is not a Tame Lion
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Percy Member Posts: 22504 From: New Hampshire Joined: Member Rating: 4.9 |
I see Roxrkool already replied, conceding that dolomite has been a problem for geologists for quite some time, but I suspect that you're using the word "problem" in a different way than she is.
When Rox calls it a problem, she only means we don't fully understand the process of dolomite formation. When you call it a problem you mean it calls into question fundmental principles of geology. I don't think any geologist sees in dolomite any fundamental problems. Since demand for scientists remains high, I assume you'll agree that we have not yet learned all there is to know. The dolomite problem, to the extent that it still isn't resolved, fits in this category of things we do not know. It is a process we have yet to fully understand, but it isn't some mystery that calls into question substantial portions of modern geology. Up until very recently, Creationists used to cite the solar neutrino shortage as evidence that we really didn't understand stellar processes, and that therefore the sun could be much younger than the estimated 4.6 billion years. The details are unimportant, but the fusion processes thought to power the sun must generate neutrinos in certain amounts. Neutrino detectors detected only 1/3 the amount of required neutrinos, and Creationists claimed this meant we really didn't understand how the sun worked. Scientists had a much different position. To them it did not appear as a great mystery or contradiction, but rather just something we did not yet know. There is more that we don't know than we know in science, and so there was nothing unusual about this particular unsolved problem, except for the fact that Creationists had latched onto it as evidence that stellar scientists didn't really know what powered stars. And then in 2001 the missing neutrinos were found. It turned out that the neutrinos weren't really missing, but that we were using the wrong type of detector. Our detectors were built for one type of neutrino, the type thought to be generated by the sun's fusion processes, but on their way to earth many of them changed into a different type of neutrino, one the detectors were not designed to detect. Once particle theory had advanced to the point where the possibility of neutrinos changing from one type to another was better understood, detectors were modified to detect the other type of neutrino and they were found. Your "dolomite problem" is of the same nature. It isn't at all something that calls into question what we already know. Physical processes outside the laboratory can be massively complex, and it's just one more thing we don't yet know. Add it to the already long list. --Percy
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Coragyps Member (Idle past 763 days) Posts: 5553 From: Snyder, Texas, USA Joined: |
Laboratory experiments using sulphate reducers cultured from the lake sediments and simulating the anoxic microbiogeochemical environment of the lakes, have resulted in the precipitation of dolomite... Hmmm. And here 3000 feet below me sits the San Andres formation, a mostly-dolomite reservoir many thousands of square miles in extent, and just chock-full of stinky rotton-egg smelling oil because of those sulfate-reducing bacteria. Probably not a coincidence.
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Christian Member (Idle past 6284 days) Posts: 157 Joined: |
jar writes: One thing a "Problem" never is. It is NEVER a place to just stop looking and stick in goddidit. I hope your not implying that that was what I was doing. I was not "sticking in goddidit". I was surmising that if Walt Brown has a better explanation for the formation of dolomite than the geologists (who apparently don't have an explanation) then perhaps Mr. Brown's scenerio has some merit.
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Christian Member (Idle past 6284 days) Posts: 157 Joined: |
edge writes: jar writes: Christian will form her own opinion of Walt Brown. Will? jar is correct. I do not, as of yet, have enough information to have formed my opinion of him.
edge writes:
Caverns? Crickets? Sure, go ahead. I don't know what you're referring to here, but would be happy to discuss it with you.
Good. Let's talk about the caverns... (crickets chirping) Want more examples? edge writes:
elicit a response from me? Was it me from whom you were hearing about how wonderful Walt's book is? When did I say that? I think I was referring to the binding, not the content. I don't understand the content well enough yet, to have formed an opinion.
Just trying to elicit a response. All I hear about is how wonderful Walt's book is.
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jar Member (Idle past 423 days) Posts: 34026 From: Texas!! Joined: |
But Walt's only explanation is goddidit. The whole idea of a Flood is solely based on goddidit. There is simply no evidence otherwise that there ever was a Flood and tons of evidence that there was not one.
Speculation on imagined issues does not add weight, however any one of the many existing evidences will falsify be enough to falsify the idea. Walt's solution for dolomite is that it happened during the Flood. The whole concept of the Flood is a goddidit solution and the Flood has been falsified. Aslan is not a Tame Lion
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Christian Member (Idle past 6284 days) Posts: 157 Joined: |
edge writes:
Not that I understand chemical principles very well, but which chemical principles might it violate?
Actually, I think we understand it all too well. THere is absolutely no evidence that Walt's scenario ever happened and it may violate several basic chemical principles. edge writes:
I think so.
Do you mean 'dissolved'? edge writes:
from the underground chambers.
'Squeezed into solution', eh? Where did it come from? edge writes: In his book he goes into many evidences for the subterranian chamber. One of which is the mid-oceanic ridge. What is the evidence for a chamber? I'll try to respond to the rest of this post later. I've done enough of this today.
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Percy Member Posts: 22504 From: New Hampshire Joined: Member Rating: 4.9 |
Hi Christian,
I appreciate that you have lots of questions, and I encourage you to seek answers to those questions just as you're doing here, but in the appropriate thread. This thread was opened for the purpose of discussing a question raised in another thread about how so much organic matter could accumulate in so short a period of time, namely the flood year. That's why the topic of this thread assumes that sedimentary limestone layers are organic in origin, i.e., that they consist of the skeletal remains of microscopic creatures that live in the water above. If you don't believe sedimentary limestone deposits are organic then that discussion belongs elsewhere. If you want to explore Walt Brown's ideas then that, too, belongs elsewhere. The last close-to-sort-of-being-on-topic post was Message 83. --Percy
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