Long build up of Sediments

Yes, as far as you go. But in some cases, rapid burial is not necessary. Often the physico-chemical environment allows organic material to remain on the bottom of the sea for a long time and even if there is degradation, a chemical signatur remains. Other times, fossil simply leave an impression, or they may actuall sink into the soft sediment and be preserved that way. There are no hard and fast rules about fossilization except that preservation can usually be considered rare. This is the exact environment of the dinosaur finds in the Morrison Formation: rapid transportation and, often, burial of remains. At least two. Sedimentary deposits can form rapidly. We have known this for centuries, even though YECs say we think otherwise. Usually, high flow regimes can result in changing environments (stream courses, for instance) and locally rapid deposition. In the Denver Formation, I see rounded, cross-bedded boulders with very round bottoms. This is from small, rapidly deposited sand bars that have sunk into the underlying, unlithified silts and clays. They look like big pillows. They might have formed in days or even hours, but the overall time for the fluvial (stream) sequence is probably thousands of years; something we may not even notice in a lifetime of watching a stream. On the other hand, just look at the stream course changes in the lower Mississippi River... very quick, even in human terms.

You are totally confusing the age the rock with how long it took to form. You could have a rock that is 10 million years old that took 1000 years to form. Alternativly you could have a 1 billion year old rock that took 5 minutes to form.

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Of course, biblical creationists are committed to belief in God's written Word, the Bible, which forbids bearing false witness; --AIG (lest they forget)

No I am NOT confusing those things. I am dealing with what the length of the period itself is supposed to be, not the age of the rock. The whole range of possibilities has been adequately covered for the rate of sedimentation within that period as well. Please do not confuse this thread at this point. It's confused enough with eight or ten posters already.This message has been edited by Faith, 03-11-2006 03:55 PM

Oh for cripes' sake. I am not confusing erosion with deposition. I am following the reasoning that says that the deposition is the result of the erosion off the land. And these processes are supposed to account for the observed ABRUPT changes from one sediment to another just along the line somewhere in those hundreds of millions of years? Give me a break.To account for the sharp demarcations between the different sediments (evident all over the southwest and in any photo of the layers anywhere) I have to imagine an ABRUPT climate change rather than a gradual one, an ABRUPT upthrusting of mountains, a similarly ABRUPT change in sea level, with no long periods of transition, as there is simply no indication of transitional mixtures of sediments, only the abrupt change from one to another.The presentation of the strata is of neat straight layers -- yes not PERFECTLY neat and straight for the obsessionals out there who want to derail the point by mentioning the differences in thickness and the irregularities between the layers that are only visible very close up.You want me to believe that the deposition of one kind of sediment came to a screeching halt and was immediately followed by the deposition of some other kind of sediment as a result of mountain building etc. What in the case of the Southwest US layers, the ones that are so visible in the formations of Arizona and Utah? What ad hoc scenario has been dreamed up to explain all that? Oh right, sea level changes there. The whole area was once the bottom of the sea. In fact the sea level rose and fell many times as I recall.It seems to me that half the land area now in existence must once have been at the bottom of the sea considering how much of this layering makes up its mass and how much must be explained by underwater formation. Or what is geology's estimation of this? Climate change really explains it? How much can mountain building explain? ===I have no more obligation to discuss this than you feel to discuss your very short answer to my question how the change in sediments occurred.I'm not even sure my guess that you were talking about abrasion was correct.I think this thread is already getting too loose and unmanageable.This message has been edited by Faith, 03-11-2006 05:37 PM

Faith wrote:

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You want me to believe that the deposition of one kind of sediment came to a screeching halt and was immediately followed by the deposition of some other kind of sediment as a result of mountain building etc.

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No. Typically, adjacent layers of differing rock types are separated by unconformities, representing x number of years of non-deposition.

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It seems to me that half the land area now in existence must once have been at the bottom of the sea considering how much of this layering makes up its mass and how much must be explained by underwater formation. Or what is geology's estimation of this?

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You're absolutely right. For example, here in North America, there once stretched a giant seaway called the Western Interior Seaway (in the Cretaceous). In a package of strata (known as the Bearpaw Fm or the Pierre Shale) found here in Canada, we can find fish, and sea-going birds, and mosasaurs, and turtles, and plesiosaurs -- all evidence that North America was once covered in a great inland sea. Note that this 'marine package' of strata that I'm referring to is bound both above and below by terrestrial strata, bearing terrestrial fossil animals (dinosaurs, little mammals, birds, lizards, etc.).

Faith, I've explained sea level change and how it affects sedimentation several times already... although come to think of it, that may be the ones you refused to read.Climate controls the amount of precipitation the continents get and microclimates control precip in the mountains, deserts, and the coasts. Water is the most efficient medium for erosion, transportation, and deposition of sediment. Without rain, erosion basically stops.Mountain building is probably the biggest contributor/source of sediment. Remember we discussed that if there were only rolling hills on the pre-flood continent, erosion would stop as soon as the shallow basins were filled? This is why. Highlands erode, valleys store (the sediment). The Appalachians are eroding today at a modest rate, but raise them 5,000 feet and erosion rates would increase many times.Sea level changes are also important because when sea levels drop, base level drops. Base level is the lowest point to which a stream can flow and this is also generally the point where sediment is deposited by a stream, because at base level, gradients and therefore stream flow rates decline. Drops in sea level cause incision of coastal rivers, which significantly increases the rate of headward erosion - which is a bit like the stream snaking it way back up into the high country.Imagine a stream is draining a shaley environment and empties into the ocean. The sediment it carries right now is mainly mud, clay, silt, and is likely saline. Now say it manages to work it's way backward (headward erosion) and breaks it's way into a small valley capturing another stream. This other stream drains a high elevation granitic environment. Lots of quartz, cobbles, feldspars, magnetite, etc. Once the original stream captures this other mountain stream, the sediment load changes from mud and clay to quartz and feldspar. HUGE difference in sediment type. Downstream where the sediment load is deposited into the ocean, the strata changes from muds to sand. It might be gradual or it could be sudden. And if the sand is being deposited faster than the ocean can rework it, then the sand stays and possibly grows out into the ocean - a pro-grading delta.These sorts of processes are happening today. We see it now and we can see it in the rock record. The most important ability a geologist has, and probably the hardest for non-geologists to replicate, is the ability to visualize these 3-dimensional environments in your head. That's why I often try to paint a picture with words because geology is a visual science.And I haven't even discussed unconformities... there are many, many reasons why sediment can change abruptly. It's not obsessive, Faith, to point out that your idea of what strata looks like is wrong. And a trained geo can see the changes in texture, cement, etc. from the road going 75 miles an hour. They are insignificant to you because you lack experience about what those characteristics represent. The devil is in the details. When sea levels rise, large portions of the continents are submerged. In the Cretaceous, sea levels were significantly higher than today and temperatures as well. marine rocks were deposited atop terrestrial rocks. When the sea levels finally dropped for the last time, terrestrial sedimentation resumed and these were deposited atop the marine sediments. This also happened in Australia.Another thing, most continents are comprised of other smaller and older microcontinents, known also as cratons (or protocratons?). North America is an aggregate of six cratons: Slave, Superior, Rae, Nain, Wyoming, and Hearne. These appear to be aggregates of even smaller and ancient cratons, usually Archean in age.Anyway, these all came together and broke apart many times throughout the history of the earth. And in between these cratons were often sea ways or large oceanic basins. As the cratons moved together and collided, oceanic crust was crushed between them, forming mountain ranges. In North America, each craton has a mountain range between it and often contains marine strata.The majority of North American cratons are situated in Canada, with the exception of the Wyoming craton, and it doesn't take a rocket scientist to notice there is a whole lotta land west and south of Wyoming. All this extra land is younger and accreted. Using dating methods, if we dated rocks in central Wyoming, northern Colorado, etc. all the way down to new Mexico, the ages would get progressively younger.I can't remember, but I think most of this new terrane was in the form of volcanic island arcs, similar to Japan and Indonesia. In between these island arcs and the continents was more oceanic crust, which also was crushed and pushed up into mountains when the arcs collided with the continent.I'm sure the three examples above are not the only way to explain continental marine strata, but it's a good start.This message has been edited by roxrkool, 03-11-2006 07:08 PM

Faith mentions: "No I am NOT confusing those things. I am dealing with what the length of the period itself is supposed to be, not the age of the rock. The whole range of possibilities has been adequately covered for the rate of sedimentation within that period as well. Please do not confuse this thread at this point. It's confused enough with eight or ten posters already."I may be able to clarify this a little better as I've had some experience with fossils and geology. The time periods in the Geologic Time Scale were originally designed to give us the relative age of fossil assemblages. No dates were attached to them in any way. Divisions in the time scale were based solely on the appearance and/or dissappearance (extinction) of fossil groups and assemblages. It had very little to do with deposition and only gave us relative information on dates (this fossil containing rock/formation is older than that fossil containing rock/formation), usually based on the simple Principle of Superposition along with overlapping correlations proximally exposed strata. This continued until the 1960's and along came TIMS, SIMS and multile ICP-MS techniques. Now geochemists had some new great tools to get into the game with. They've tested the majority of the geologic rock record and found that the old paleontologists did a pretty darn good job in putting all of these fossils in order. In fact, if you ask me, this affirmation of the relative time scale with radiometric (absolute) dating techniques is not only the bedrock of modern geology, but also extends into chemistry, evolutionary biology and many other fields.This message has been edited by Chuckdarwin1809, 03-11-2006 11:25 PM

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"All gods were immortal" Zina G.

Nice post, but just to let you know Faith has already had this explained to her by someone else who had experience with fossils and geology. Which means don't get your hopes up.

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holmes
"What you need is sustained outrage...there's far too much unthinking respect given to authority." (M.Ivins)

You are being given very good information by rox and edge, and I do not understand why you keep repeating your original position in the face of what they are saying. Particularly claims that ancient dates were believed and so imposed on geologic theory, and things like... ... which suggests you do not understand the history or explanations of geology. Not to mention statements like... ... which suggests you have not studied actual maps of strata, beyond perhaps those dealing with surficial (exposed) cross cuts of the grand canyon.I will try to run through this quickly, again, with links for further information. As has been noted, the conception of ancient dates was NOT an intrinsic part of geology. The identification of layers of sediment does not require knowledge of dates or even concepts of them. I assume you would at least agree with that proposition, that we can identify different strata based on differing compositional material.It was out of identifying strata that stratigraphy emerged. Read the link for a more in depth discussion, but important to note... This was without a concept of absolute dates, or dating methods. Where and how did "deep time" emerge?... This clearly states that deep time was emerging as a concept BEFORE evolution, and it was from looking at composition of strata and how those strata interact with each other. One of the most common relative dating methods was the principle of original horizontality and the Law of Superposition. Again, read the link to get a more detailed explanation. But from this there are some important notes... Steno predates and could be called the prefounding father of geology, most certainly stratigraphy. His work began the journey and what happened to him is of note and bears on this discussion... After enough investigation into geology Steno began to see problems for his faith and renounced geology to re-embrace theology. Note above that Steno (and this is before deep time was proposed) realized that the Flood was inconsistent with the entire geologic column (as you have suggested here). Thus you cannot assert deep time, or renunciation of scripture, was itself a prereq for dating or finding inconsistencies between Flood mythology and what is in the rock, particularly when looking at the entire geologic record. Steno was dealing with an incomplete record and had already found problems, despite his piety.Indeed if one looks at the actual strata one finds that demarcations must be made to try and save Flood theory, which actually hurts YE theory... and with later discoveries only further hurts Flood theory. Furthermore, this is without addressing issues of dating based on the obvious FACT that in clastic rock the original rock fragments had to have formed and then eroded (adding to deep time) in order to become part of another rock.Now lets look at your claim regarding rock being layered smooth and straight. As mentioned above, faults and folds have been found in rock. Here is a link to a description of Appalachian strata structure. Scroll down to the middle of the page where it starts in on ramps and thrusts to find a cross cut map which is anything but horizontal and straight. Or look here. Or here.My apologies for not being savvy enough to insert the pictures into my posts, but they are there and you need to address their existence. It does not look like Grand Canyon, which is what you seem to want to hold onto as your only example of strata. It is mixed up and not in ways that could have occured if it was all loose sediment swirling around. Vast layers had to have settled and solidifed, and then broken and shifted.This is part of the geologic record, please explain.I will leave it here for now, but as a forewarning I have not begun to discuss igneous rock intrusions into sed strata. These formations... dikes, sills, plutons... also force greater relative dates as strata it pushes through or borders with must have been laid down earlier and fully hardened, before the igneous structures which then had to cool (which means time), before sed layers were deposited on top of them.There is more in the maps of earth than were imagined in your philosophy Faith. Perhaps you will have to reach the conclusion of Steno (abandon all discussion of geology to preserve faith), but you cannot pretend that the geologic record is as you suggest, or that your conclusions are reasonably attained from that record. Even Steno could not wave his hand that hard.This message has been edited by holmes, 03-12-2006 01:07 PM

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holmes
"What you need is sustained outrage...there's far too much unthinking respect given to authority." (M.Ivins)

It seems to me, then, that in the process of dating by fossils the problem of the discrete sediments and how to explain them was overlooked. The fact that these separate sediments characterize the time periods certainly raises questions about the timing of their deposition over the allotted time for that period. It also raises the question in my mind how just that one and only sediment COULD have characterized so exclusively a period of many millions of years, 50 to 100 million perhaps. Although the particular sediment may vary over the globe for a particular layer or time period, still it is always characterized by just one sediment (or sometimes particular sedimentary mix I think) for the entire time allotment wherever you find it. To try to explain this by local factors overlooks the global nature of this phenomenon.

Are these unconformities ever seen dividing the SAME rock type, right through a layer instead of between layers? Why would nondeposition always occur only at the end of a long long period of deposition of one kind of sediment and not during? Interesting. I thought the order of fossil deposition always had the more "primitive" on the bottom.And of course an inland sea fits well with a global flood. There must have been many such seas that remained after the flood and only gradually drained away.

Explain this with an example. You may use the appalachian crossections I gave above to match to any other crosssections from around the world, to show the "global nature of this phenomenon."I might add that you seem to be ignoring the stratification problem (up and down the record) of life within sed strata. How do strata with similar seds (esp fossils) wind up in vastly different areas, including separated by other rock formations (igneous/meta), if the sole active force was a 40 day Flood? Even suggesting that Flood activity involved volcanos, does not explain nonvolcanic igneous intrusions, nor metamorphic areas which must have been from solid sed stone exposed to great heat of an igneous intrusion.The above is best explained by solidification followed by mass actions, rather than settling and solidification, with volcanic activity shooting up lava here and there.

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holmes
"What you need is sustained outrage...there's far too much unthinking respect given to authority." (M.Ivins)

I'm sorry, Holmes, I have way too much to deal with on this thread as it is, so please forgive me if I don't give your post the attention it deserves.All I want to say now is that the fact that the strata have been tectonically buckled in certain places such as the Appalachians has not escaped my attention, and isn't relevant to the building up of the strata in the first place, which obviously occurred horizontally.This is also the case with the various uncomformities people bring up. Whatever happened AFTER the layer was put down isn't relevant to what I'm saying, which is about the building up of the layer in the first place.This message has been edited by Faith, 03-12-2006 07:23 AM

The global nature of the stratifications is not in doubt, Holmes. Roxrkool discussed it earlier on when she talked about how geologists all over the world had noted the same basic phenomena and there was a global effort to map it and consolidate it all into one global picture of the time periods.I am trying to keep the focus on the problems I see with the rate of sedimentation on the Old Earth model, and avoiding the Flood.This message has been edited by Faith, 03-12-2006 07:28 AM

Age determination is not capable using the fact that strata are deposited horizontally. The best one gets is relative ordering. Though as I point out, even Steno noticed problems for the Flood relating to the entire geologic record (which is what you have suggested) from simple relative ordering combined with content.Age determination is best made when there are irregularities. The reason why is that that means the rock must have solidified first, before the action which occured to it. If you have that followed by more layering on top, you now have greater time involved.If you are going to base your entire theory of what happened based simply on sediment buildup in clean layers, then you are arguing a strawman... it isn't what modern geology claims to have seen or what it based dating on.

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holmes
"What you need is sustained outrage...there's far too much unthinking respect given to authority." (M.Ivins)