Earth science curriculum tailored to fit wavering fundamentalists

Could you please refer us to a deposit of a single silt bed that was distributed all over the earth by ocean currents?

I'm sure that the profession appreciates your opinion, however, metamorphic zonation in the eroded Appalachians suggests otherwise.

Well, considering that this is what you wrote: (bold added)Yes.

That doesn't answer my question...ETA: And coal seams are not global deposits...Edited by edge, : No reason given.

Actually, there is from several lines of evidence.Metamorphic minerals suggest that something more than 2 km of rock have been eroded from the current level exposed in the Appalachians. This diagram shows several series of regional metamorphism in the continental setting, to which the Appalachians would have been subjected. Note the depth (pressure) values by the time one gets to granulite grades of metamorphism.Remember we are dealing with continental crust which is on the order of tens of kilometers thick, but we are also stacking two continental sequences, one over the other, so thicknesses can loom quite large. Another line of evidence is the immense quantity of eroded material that was transported west to form the great sandstone deposits of the western US.Here is a quote from Wiki: Alleghanian orogeny - Wikipedia

This is all good stuff and it can be backed up.One interesting find I had today is that there is some evidence that the Appalachians were so high and long as to have influenced global climate, possibly initiating an ice age and an extinction event. If there is interest, I'm sure we can track down the reference again.(ETA: I just saw your previous post to this effect. Sorry.)Another underrated feature is the amount of sand found in the Mezozoic of the Western US. Provenance studies show that much of it was derived from erosion of the Appalachians. That would mean over a thousand miles of transport by a transcontinental river system.Another thing to keep in mind is that we are being America-centric here. The Appalachians are part of a near-global series of mountain-building events stretching across northern Europe into the the Baltics and Eastern Europe. This was a major event in the history of the earth. Edited by edge, : No reason given.

So... creationists are not fallen?Their interpretation of the bible is infallible?

Ah... still nothing of subtance, just complaints. Not really. Since the higher-grade metamorphic rocks are present at the surface, it is reasonable to assume that they were actually once at a much greater depth.

Well, then, you were wrong. You said that it was due to the type of mountain range.Now it has to do with the rate of erosion.And actually, I agree. Higher mountain ranges are subject to higher rates of erosion. When the Himalayas are the same elevation as the Appalachians, they will be eroding at a similar rate. I have no idea what you are trying to say here. Have you seen cross-sections of the southern Appalachians? Yes, it would be an interpretation of the evidence.What have you got?Oh, that's right. If we disagree with you we are crazy.That makes sense.

When I learned to tie my shoes, I was wrong at first...I suppose that means that shoes don't exist?

Well, it is a plausible explanation.The point here is that the kinds of C14 values we can see with modern techniques (such as the ones that YECs expound) are on the order of counting individual atoms. It starts to become what we call 'background' values, in other words meaningless values because they are always present due to a number of extraneous inputs. Remember, 'the data is in the signal', not the noise. YECs focus on the noise...Now, where does this noise come from?Probably a number of sources, the most common of which is contamination (and with a common and light isotope, C14, this is a very real problem). But there are probably other sources (also under the heading of 'contamination') by recently produced C14. The commonness of radioactive minerals containing uranium and/or thorium in the earth's crust, along with the abundance of nitrogen in diamonds, etc., is just too much of a coincidence to ignore.It also turns out that the residence time of ground water (ultimately derived form rain water (and atmospheric CO2)) is on the order of tens of thousands of years. Well, guess what... that impinges on the range of radiocarbon usefulness in dating. So, if a sample were exposed to groundwater, some exchange of carbon might be expected causing another source of contamination.Another coincidence?Okay, all of the contamination that I am talking about occurs in the ground, before sampling. So notice that all of the heroic efforts referred to by YECs to reduce contamination in the lab are essentially meaningless. No matter what you do, contamination has already occurred...So, ignore that part of the YEC argument. Most contamination occurs before the sample gets to the lab.I guess my point is that there are just too many ways, including blunders by the lab, to be concerned with extremely low values of C14. Edited by edge, : No reason given.

Exactly. Extremely low values are essentially meaningless. In pure, unaffected diamonds, you can see the theoretical limit of about 70ky ages. Few actual, natural materials can make this hurdle.Good reference. I've been looking for something like this.

I guess you didn't hear that Wikipedia is in on the old earth conspiracy...

Having worked with both uranium and coal deposits, I'm still kind of partial to this argument... I think that local conditions are important and probably cause the widely varying numbers for C14 in coal. In fact, there are more abundant radioisotopes than those of uranium. Thorium is about 3 times as abundant, IIRC. Not only that, but we should probably be dealing with daughter products more than the uranium itself. I think if we just look at the radon flux through coal beds for instance, we might come up with a very different viewpoint of what is happening. One of the biggest problems with coal is that it fixes a lot of mobile elements. In some uranium deposits a lump of carbonized wood can trap enough uranium to make it a very rich pod.

In fact, the Oklo reactor that has been discussed here previously was probably formed by the same process and it reached not only minable grades but fissonable concentrations.Natural nuclear fission reactor - WikipediaI might add that the roll front deposits and coal beds can be found in similar sedimentary environments such as exist on the Colorado Plateau and in Wyoming.