Someone who admits he knows nothing about geology, asking where the colum came from?

funky: You might enjoy The Map that Changed the World by Simon Winchester - not really about the worldwide geologic column, but about William Smith, the man who but the British part of it together back in 1815. It gives a pretty good reconstruction of what his reasoning was.

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layers in the geologic column found in North Dakota and at least 26 places around the world.

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And please don't forget that thousand-foot-thick layer of salt in the midst of all those North Dakota rocks. That's sodium chloride, soluble up to 26% in water.

Yeah, there's that much salt, like Randy just posted- probably not in Morton's location. We had to come up with very peculiar cement mixes to be able to cement oil wells up there - regular ol' cement doesn't stick to pure salt very well. I don't remember/never knew the exact geography of where the most salt was, but our company serviced those wells out of Williston.There's salt like that in South Arkansas and beneath the US Gulf of Mexico coast, too.

Maybe the discrepancy is partly that sodium chloride itself is only 2.67% by weight in (standard) seawater. I get 2.74 x 10^13 kg of salt per cubic km of water from this. Still tough to get to evaporate in a rainstorm.

The whole core is iron (or iron-nickel alloy, maybe with a little iron sulfide), solid at the center and liquid around. The mantle is above the core, and is silicate-based rock - but hot enough that it flows very slowly, like "molasses in January." The crust, that we live on, is a skin of rock about as comparatively thick as the peel of an apple.
The liquid iron generates the Earth's magnetic field, and the fluidity of the mantle drives the "lava lamp" of plate tectonics.

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If you can at all help clarify/support/refute my doubts as to the radiometric dating I would appreciate it. thanx

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One little chunk of evidence in favor of the constancy of radioactive decay rates that is observed rather than relying on some quantum-mechanical proof has to do with supernovae. Most of the light from a supernova comes from the energy given off by the decay of nickel-56 to cobalt-56 and on to stable iron-56. These half-lives are short - days to weeks, if I remember right, and both give off lots of precisely characterized radiation. The thing that shows the constant rate of decay is that the half-lives calculated from a nearby, naked-eye supernova are identical to the half-lives calculated from one a billion light-years away, that exploded a billion years ago: the light from the explosion is only now getting here. If the decay rate was different in the past, we would see a difference in the fading-out of distant and nearby supernovae.

[QUOTE]Originally posted by funkmasterfreaky:
[B] Okay then now i get curious how we know the speed of light? How was this arrived at? Does it's speed decay, or maintain at the same rate forever?[/QUOTE]The decay rate of nuclei like nickel-56 can be calculated, sort of, by equations that depend on the speed of light as one of their constants. If the speed of light had changed, the decay rate and energy of decay would have changed too, and observation shows that they haven't.