Geology isn't my strong point, but I'll have a go.
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Originally Posted by Phi
So does this mean that ever-deeper layers of earth are forming globally?
That earth is growing?
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No, I'm afraid not - there are different rates of erosion and deposition around the world, unique to different local conditions.
Do you remember those classic drawings of how dinosaur bones are preserved in sedimentary rock - how the dinosaur dies, is covered by successive layers during the fossilisation process - and then the layers are slowly worn away until the fossilised dinosaur bones are exposed millions of years later? Same story.
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Originally Posted by Phi
If so, are oceans receding as land rises, or is earth growing beneath the oceans as well and at similar rate,from decay of sea life?
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Coastal areas may change with rising land levels - but there's usually a trade off somewhere. The pressure of the Artic ice shelf tends to push Northern Britain down, which in turn lifts up the south of England from sea level (thus exposing vast cliffs of skeletal crustacean remains - the famous white cliffs of Dover.
The process isn't huge - but apparently is measurable. I think we're talking meters of difference of the hundreds of miles of land between the end points
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Originally Posted by Phi
Is the study of strata-layers for archaeological digs hard or soft science/ meaning is there a great deal of subjective opinion involved?
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It's a form of extensive guess-work, I think is the best answer.
One of the main ways of dating archaeological strata is by comparison of the pottery types that are unearthed. Styles and compositions can actually be readily traced a lot of the time to very identifiable locales and time periods of production. The sites of origin are usually dated according to a range of other dating methods.
Thus if a certain river in Suffolk - which has a certain unique isotope signatuer in its mud - became a site of pottery making over a period of, say, 200 years - then the expectation would be that if another archaeological site started turning up remains from pots containing that unique isotope signature, then it would not be unreasonable to presume that these pots were discarded sometime during or close to the period of production.
Apparently, it's an extremely good way of determining the relative age of different soil stratas in archaeological digs.
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Originally Posted by Phi
Given two archaeological finds the same age:
Would a find made in a lush jungle be deeper due to much more leaf matter than a find on the relatively barren steppes, perhaps?
Does anyone know the rate of growth per thousand (A tiny amount geologically speaking)years? Has it been broken down to even smaller time frames?
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Again, it's an issue of erosion and deposition. I'm not sure what the general trends are and if these apply to this specific example.
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Originally Posted by Phi
Can information be extrapolated regarding how large earth was when the several oldest remains were found? When dino's were here? How much smaller was it?
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We're essentially talking about an essentially closed system - so it is expected that there is pretty much the same now as there was then.
Hope that helps - but I freely stand to be corrected by anyonhe else.