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Old 17th November 2012, 04:46 PM   #27
Dinwar
Penultimate Amazing
 
Join Date: Jul 2010
Posts: 16,668
Originally Posted by Jodie
There is debate as to whether the actual site is as young as some of the artifacts found there since some stones were found to be buried under 6 feet of soil in an area where soil erosion like that is a slow process
In the immortal words of Peanut: How do you know?

That's a serious question, by the way. The issue is, you're running head-first into the concepts central to Neocatastraphism. It basically works like this: low-amplitude, high frequency events dominate temoprally. They happen all the freaking time--sometimes quite literally (ie, they're constant processes). However, they tend to get overprinted by low-frequency, high-amplitude events. For example, tides in some areas deposit a certain amount of sediment each day. It's a small, constant amount in discrete layers. However, when you examine the geological record you notice that these layers are absent--what you see are tempestites, where storms re-work the sediment. Tides are low-amplitude, high-frequency; storms are high-amplitude, low-frequency. This is quite common in the geological record.

The specific application in this case is that we can't necessarily simply look at what's happening right now in these areas and say "This has always happened exactly the same way; therefore 6' of soil=X years". We'd need to examine the stratigraphy to determine exactly what processes were going on at the time of deposition. Depending on how you're using the term soil (there are many) they can be deposited in a surprisingly short amount of time. I know that the Modesto and Riverbank Formations in the San Joaquin Valley include some layers that are fairly thick and which were deposited remarkably quickly.

Even high-frequency events can make it impossible to analyze, however. Soils are frequently full of critters, and critters have burrowed for about 600 million years (depending on your interpretation of a few trace fossils). This churns up the sediment, until in some cases all you see is a homogenous block of sand. Really annoying, by the way--you can lose a few million years' worth of data very easily that way. A few thousand is easy. What that means is that it may in fact be impossible to know just how long it took to accumulate that sediment.

This is what I meant about this stuff seeming easy, but being incredibly hard. It sounds very, very easy to look at how thick the dirt is and figure out how old it is. The practical applications are incredibly complicated, however, and even experts often simply don't know. Soils are extremely complicated ecosystems, and paleosols have all those complications plus taphonomy and novel geochemical processes. This isn't something you can read a few articles online about and be knowledgeable in it. It's something that requires fairly intense study for years. I spent a semester in grad school studying ripple marks and I don't pretend to know all there is to know about those structures, and that's just ONE of the things someone doing this research will need to be able to interpret.

Quote:
Why couldn't that repeat itself over and over again in the last 200,000 years.
Provide evidence that it did, and we'll talk. Until then, there's no reason to think it did, by definition. We can speculate about why (and that's really all it is, mere speculation), but the fact remains it DIDN'T--unless someone can provide the evidence that it did.

Originally Posted by HansMustermann
For example the guys who first made iron swords pretty much razed and replaced whole civilizations which were still using bronze.
Actually, the first swords WERE bronze. Tangless bronze swords, to be exact. They didn't exactly sweep through other societies, though--spears and the like were more effective for a long time. Iron swords did put an end to most bronze-sword-using societies, however.

A better example would be chariots. When Egypt was invaded by some group (Hittites?), they were wiped out because the chariots cut down whole armies. Then the Egyptions learned how to use them, and wiped out their invaders with their own technology.
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