Growing the Geologic Column

Here is a link to the geological stratigraphy of the Olduvai Gorge in Africa.General Chronology and StratigraphyAnd here is one chart from that essay: Note the intermixture of volcanic and sedimentary layers.Now stop with the nonsense that volcanic layers don't form a part of these various geologic columns!Edited by Admin, : Change image background to white.

She probably doesn't know that a tuff is volcanic.

Well, since you asked, yes. That would seem to be the problem.By analogy, we have the concept of European history. There is no single book, or tapestry, or painting that records all the details of our activities over the last, say, three thousand years. Yet out of many isolated records, we can assemble a composite that allows us to place those isolated observations in a broader context. If we read all the documents found in the area of an Italian village we would have a record of local births, deaths, mayors, murders, floods, famines, and so on. If we read the history of a French village, the details would be different.Yet, underlying the vast jumble of different details, there would be the common threads of seasons changing, the rising and falling of Popes and Kings, the waxing and waning of plagues, changing styles in art and technology, and so on. Out of this we could develop a mental image that we call "history" ("the geological column"). And, crucially, we could place seemingly unrelated and quite different small events, that took place in geographically isolated areas, into correct relationships with each other by referencing the larger flow of history around them.When considering this history, it would be, well, odd to consider an outbreak of typhus in a particular city in France as somehow presenting a challenge to our image of history because it was not recorded in a different city in Italy. To further claim that this occurrence ("intrusion") of typhus ("lava") into the records of the French town was not part of history ("the geological column") would also be odd, to say the least.What Faith cannot seem to grasp is that her questions and objections about the geological column (read, "the broad, overall history book of the earth") are very much like this. Going on, and on, and on, about a collection of discontinuous geological minutiae is precisely as ridiculous as complaining that the birth records of Luigi's ancestors in San Gimignano don't address the details of Jose's Spanish ancestors in Madrid. Proceeding to then complain that, since neither record can be found in Europe - A History by Norman Davies, history texts are somehow dishonest, is, well, make up your own adjective.Throughout history, some churches and palaces have burned ("eroded") and local records have been lost. In other places, detailed local histories have been written and preserved, and information is contiguous for generation after generation. None of these local variations and discontinuities change the broad, clear picture of of our history that can be developed by integrating all the information available. The fact that Faith gets hung up on the word "column", and manages to throw sand in her own eyes by conflating the different linguistic connotations and physical implications of this word when used in different contexts, suggests that your comment above goes directly to the point: the map is being crumpled and torn and strewn about in a willful attempt to obscure the road.ABE: As always, though, the information provided by the more geologically literate is appreciated by the honest learners reading here.Edited by Capt Stormfield, : No reason given.

Curiously it doesn't matter what the materials are that are being deposited -- the critical point is that material is constantly being deposited and is building up in the geological period call "now" ... No you don't need to explain, you need to learn: sometimes layers are all classified as one type of material; sand for instance covers a range of sizes and can be made up of different material of origin ("black sand" is finely ground volcanic rock), and it is defined by size more than material:Sand Definition & Meaning - Merriam-Webster

quote:

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1.a : a loose granular material that results from the disintegration of rocks, consists of particles smaller than gravel but coarser than silt, and is used in mortar, glass, abrasives, and foundry molds
  b : soil containing 85 percent or more of sand and a maximum of 10 percent of clay; broadly : sandy soil

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bold added for emphasisNote that gravel and silt can be the same materials but in different sizes.In addition there are many sedimentary layers that consist of mixtures of rocks, gravel, sand, silt and clay -- typical material found after spring storms being deposited in lakes. In every area the layers in the local "column" (what you would find if you took a core sample) would consist of some soil layers (non-lithified), and different layers at different depths. The depths represent relative age (by the law of superposition - see Dr.A's topic).You would also be able to take a similar core a hundred feet away and find some layers not in the original core and some layers missing that show up in the first core. Comparing the cores you would be able to relatively date where these discrepancies are in an overall composite column showing all the layers in the two columns in their relative age position.As we can easily see, erosion can remove a layer in one location while leaving it intact in another, and deposition can add a later in one location while not affecting another.Note that the geological periods were all defined by relative dating of layers in a composite column built up in this way from many sources long before radiometric dating arrived on the scene.Volcanic ash covers a large area after an eruption, and this is a layer in the column that occurs at the time of the eruption and is usually referred to as 'tuff' in the column (as has been noted in Lake Suigetsu layers, which then date those eruptions). Lava flows would also be a layer formed on the surface at the time of eruption, and thus show up in the geological column at the time of the eruption.We can date volcanic tuff in the mississippi river valley to show when the huge caldera in yellowstone park erupted, just as we can see occurred for Mt St Helens.Enjoy.

I love analogies and this one is apt due to the historical theme. I'm sure that Faith will disagree since analogies are usually lost on YECs who see things only in absolute terms. The 'geological column' is THE COLUMN, no way around it.I also think that the utter denial of evidence for old ages is central to Faith's reasoning, regardless of the fact that she 'uses the same information'. It is simply not possible to have all of these events occurring in an abbreviated geologic history, so they can be safely ignored. That puts an insurmountable distance between her and reality.

A lot of the point is that pure sands are not all that common. Not only do you see mixtures of composition, but also grain size. I think that most sandstones are not pure sand, nor pure quartz. That's one reason we have a number of classifications of sandstone and various modifiers. That is one occurrence of sand. Black sand beaches are common in volcanic areas where basalts make up much of the section. Hawaii is an example. Other types of 'black sand' could be some basaltic, fine grained pyroclastics; but my favorite is what you get when you pan down stream sediments for gold. That black sand is largely higher density grains such as magnetite and will includes gold, if present. It makes a nice contrast to the gold grains. "Sand" refers to the grain size. The "black" would imply some composition.ETA: I see that the topic is drifting here, so let me add that radiometric dating has solidified the framework of the geological column and has mainly used igneous rocks in the past. There have really been no surprises as far as order of the strata and their absolute ages. At first, they were kind of surprised to see how old rocks are, but they never had an absolute measure before. Edited by edge, : No reason given.

I get it all from geology sources, where else would I get it? And you can cut the abusive tone of voice.When you look at the diagrams representing, say, the Grand Canyon, you see separate identifiable unmixed sediments characterizing most of the strata. They are all sandstone or all limestone etc. The Coconino is a huge block of sandstone; the Kaibab is a block of limestone. This is the same with the Grand Staircase. There are some layers that are made up of more than one sediment type, but usually in shallower layers. Mixtures may occur but they are far from the standard from what I've seen, read and heard. Your own posting of Pennsylvanian and Mississippian layers way back on the other thread shows limestones, not a mixture.And, looking up the Niobara formation I find that it too is characterized by identifiable sediments: Chalk
Limestone
ShaleSeparate identifiable sediments. Edited by Faith, : No reason given.

It would help a great deal if you wouldn't answer the posts I've addressed to others as if they were addressed to you. Percy's OP is what clearly divorced the column from the time scale. If you differ from him in that then please address your objection to him and not to me.Meanwhile my point to him was that wherever I find the column discussed it is discussed in connection with the time scale or in fact as synonymous with it.I may come back to your post.Edited by Faith, : No reason given.

Geology invented the Geologic Time Scale. It is often associated with the particular sedimentary rocks of a particular region, though overall it is an abstract concept that reflects the rocks in all regions where they fit the concept, which taken together I've always known as the Geologic Column. It is always associated with SEDIMENTARY rocks, not igneous or any other kind. It has NEVER been applied to all the rocks on the planet but only the sedimentary column where it is found, yet now some of you are pretending there is no such distinction. It is of particular interest for the fossils that are the major evidence for the Theory of Evolution, which are found only in sedimentary rocks.This is how I have always encountered it, all over the internet, in books and whatnot. Now to find this common ordinary phenomenon challenged here is perplexing to put it mildly, and the tone of the Geologist in particular is outrageous, accusing me of the idea as if I'd made it up myself, and more outrageous things than that.For whatever reason you all want to deny what I've always understood to be a standard principle in geology. This hits me as some kind of bizarre psychological twistedness frankly. In any case I don't need the abuse.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Well, then, it's pretty clear that you misinterpret the descriptions and make up a lot of stuff. I prefer to think of it as 'critical'. Take it however you want. You mean like the Hermit Shale? Or the Bright Angel Shale? Or maybe the Muav Limestone? Interesting that you should mention the Coconino. It's not a water lain sediment and is probably more pure than most sedimentary units.Oh, right! It's not eolian according to Faith! Okay, let's check it out: Then your reading is incomplete and your experience is non-existent. And I haven't even gotten into the Supai Group. For simplification, yes. However, pure limestone is a rare and valuable commodity, and sandstones are too contaminated to be be flux in iron foundries. So, do you know how many chalk beds there are in the Niobrara? Do you know that there are marls (essentially dirty, fresh water limestone) associated with them? Do you know that some of the shales have bentonite? Even the Fort Hayes has small amounts of shale in it and it is certainly not a medical grade of limestone, though it does make a good source of cement. Yes, many in the same unit.
Edited by edge, : No reason given.

I'm sure you have interpreted the reports correctly, without any religious bias.

Yes I have, though you like to misrepresent things I say to add your own strange opinion of what you think I believe. There is no way to have an honest discussion with somebody who acts as you do.ABE: And now because I've said the sedimentary strata are of different sediments you are trying to prove me wrong by giving detailed descriptions of their contents, although of course I'm referring to their COMMONLY UNDERSTOOD identity as of a particular kind of rock. Which can be seen even in the walls of the Grand Canyon from a distance. DIFFERENT KINDS OF ROCK. Different colors for instance, different degrees of hardness. You are a shyster Mr. Geologist. Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Pot, meet kettle!It is very difficult for us to have an honest discussion with you when, by your own admission, you feel free to ignore any evidence that does not confirm your religions beliefs, you change definitions from those which have been worked out by science over decades or centuries because they don't fit your beliefs, you just make things up as you go, and you have shown that you are approaching things exactly opposite from the scientific method. And to make it worse, you don't even agree with most other creationists!"An Army Of One" was the slogan of the US Army, but you seem to be trying to take it over from them.And you think this makes it easy for us to discuss these things with you? Gimmi a break!You should be thankful we're as polite as we have been.

Faith, you know how I keep telling you that you don't know anything about geology? Well, this would be a case in point.One sees this again and again with creationists, they become obsessed with a subject which, paradoxically, they're not remotely interested in. Could you not bring yourself to take an interest, find out the first damn thing about the rocks you're talking about, such as their composition? And until you've done that, could you stop prancing around in public pretending you know better about geology than geologists do?

Well here he is again, the master of saying absolutely nothing about the subject while accusing me of terrible though undemonstrated offenses against the great god *Geology*abe: That is what I have always understood the Geo Column to comprise: STRATA, which are of SEPARATE IDENTIFIABLE SEDIMENTS. If you want the small print, it includes the caveat that I am not talking about Perfection and I am not saying it's identical everywhere on the planet, and I am not saying any one place represents the whole column etc etc etc. I am only saying that they are separate identifiable sediments and they can be seen in some places to quite a depth too. I've always understood this column to be the basis for the Geologic Time Scale. What offense I am committing with this understanding I have no idea.Edited by Faith, : No reason given.Edited by Faith, : No reason given.