Summations Only

Well we know for a fact that it happened so it is not impossible. But again, they seldom end up flat or straight.A good example is the Great Unconformity in the Grand Canyon. There about a billion years of material is simply missing. We can get an idea of what should be there by looking at other columns but what really was there is truly missing. That particular area saw far greater erosion and weathering than other areas at the same time.The reality is that some areas get pushed up and where that happens a layer gets worn away while other parts of the same layer remain.What may look as flat and straight sections when seen from a distance turn out to be far from flat or straight when examined in detail. Time. Not necessarily greater depth of material but longer periods of time. The process is continuous and simply goes on day after day but over really long periods of time.

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I was merely referring to those illustrations given for a particular time period, as I posted in Message 333. They represent the whole time period, one illustration for the whole time period.

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So they show a "typical" landscape for the period (maybe not even typical, just a reconstructed landscape). There really isn't any significance to showing only one.

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You are right it's a lot more complicated than that. So now it's a landscape for a rock and more than one for time periods that are represented by many rocks.

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I don't really like the concept of "a landscape for a rock" because the whole idea that you can count individual landscapes over time seems impossible. As I said earlier the landscape will always be changing, so when do you decide that it has become a different landscape ? I cannot think of any clear-cut criteria. (And in those cases the landscape gets eroded back, material that was once on the surface will be on the surface again, so maybe some rocks represent two landscapes).And let us not forget that the strata covering large areas that you like so much are generally marine, so if you want to include them you have to count seabed as a landscape.

I don't see why this puzzles you. Yes, every layer of sediment either has to be removed by erosion or stay where it is. This is not so much a physical impossibility as a logical necessity. Usually they move. It's not like these things happen overnight. If, for example, the seabed in some area is uplifted to become a desert, it's not going to happen so quickly that the fish are going to get stuck on top thinking "Damn, why's it so hot and dry all of a sudden?" Lots of sediment is deposited quite flat and covering a huge area. Marine sediments in particular.Edited by Dr Adequate, : No reason given.

I always look at some examples we see today. As sea levels rise coastal areas change from shore to sea. The Appalachians are a multi period landscape with the soil representing this period while the bedrock is a period both today and from almost 500 million years ago. Where glaciers are retreating we see a changing landscape. Many of our fossil finds are where older material gets blown away and reveals a landscape from long ago as it exists today. Where the Sahara is expanding the landscape is changing from forest and farm land to desert.

They do? Really? They represent the entire planet with all of its different environments and ecosystems?Wow. I never saw it that way, even as a child. As I've often said, Geologic Time (the time scale) is like a tape and the rocks are what is recorded on it. And like a tape, it might have gaps where nothing is deposited or gaps where it has been erased by erosion. Edited by Adminnemooseus, : Fix 1 quote box.

One reason it is so difficult is because you use terms of your own, non-standard definition.

I don't know what you mean here. Who has forgotten that the sediments turn to rock and become part of the geological record? And the problem is?Though I might quibble over what that 'great depth' is. Here is where you leave the rails completely. All layered sedimentary rocks are strata. Are you trying to say that only the rocks are left?If so, what's the big deal? Isn't all of that fairly obvious? What next time period? They are simply younger. What do you mean by a 'time period'? Why not just say that the next layer will be a younger rock? Again, what do you mean by 'the geo column'? Whatever is there is there. The topmost layer of sediments or rocks is usually gone. Remember my description of terrestrial systems? They are in a state of long-term erosion. What is impossible for me is to understand your reasoning.Everything you say is fully accounted for by mainstream geology.But, you reject old ages, so you cannot even fathom how geological processes work. The same thing that happens now. They move.Of course the dead ones don't. If they are lucky they become fossils in someone's collection. Sure, marine sediments look like that even when they are still sediments.

Yes, there is always a landscape as long at there is land.Regardless, if it is preserved in the record it is a surface (erosional, if on land) and not a rock per se. In general terms, I would call it a primary structural element. It would be paleotopography.

That's a laptop specific thing. On my computer F11 does nothing unless the browser window is selected. In that case the browser goes into full screen mode.

I've been puzzling about this sentence.What is it saying? Very few things are 'exactly' alike in the world of stratigraphy.

It's utterly trivial, all it means is that we have to end up with what we see that we ended up with. Why Faith considers that a problem she has yet to explain.

I've been raising issues that I've hoped would become the focus of discussion. I strongly encourage everyone to concentrate on these points. Please don't respond to me because I'm not a participant in the discussion, just a moderator. Screen brightness is adjustable. It can be diminished to view the images, then turned up again. Or you could try sunglasses.Please, no replies to this message.

I said a while back that I wanted to go through some posts starting with this one so I guess I'll try.I'm glad you agree that I said something "clear, straightforward and sensible" in that paragraph because the whole point was to prove that I do understand a lot of how geology works.The questions you say show a lack of understanding are mostly my attempts to get at particular observations about the relation between the rocks and the landscapes we are discussing. Some of them are rather klutzy questions I agree, but then without tracking down the context of all of them I don't even know what I was getting at either. However, I think the loud complaints about my lack of understanding come from that sort of effort, not from a lack of understanding of geology.

Sorry, but I am forced to differ.Anyone who thinks that geology began and ended with a mythical flood really has a minimal understanding of geology.

I don't know if your characterization above is correct or not, but it is clear that you have made a solid effort to understand. That effort has not always been so apparent.It might be helpful to your presentation if when you say that something is impossible that you give a reason along with that statement. If you cannot do that, then perhaps that means that your own reasoning has not solidified.But that's just my own impression. YMMV.