Earth science curriculum tailored to fit wavering fundamentalists

In fact, we need 'thermal' neutrons IIRC.Here is how they source neutrons artificially: You probably don't need this, but for those of us who are nuclear physics-challenged, here is an example decay chain for U/Th: As Petrophysicist indicates, this is a very difficult task, because of the dynamics of the system. However, I read an article that suggests a total flux from the earth of 0.75 atoms of Rn222 per cm2/s in continental areas. I would guess that local effects could be large.(edit Ra to Rn...)Edited by edge, : No reason given.Edited by edge, : No reason given.

The difference being that, in speleothems, the uranium would be fixed as some kind of oxidized mineral as an efflorescence from aqueous solution. In coal, I would expect uranium to be in a reduced state.

A few additional comments on this subtopic...Normally, we would consider sedimentary rocks as undateable by radiometric methods. However, if we were to date the actual mineral grains, we can come up with meaningful data. Some of these grains will be derived from pre-existing igneous rocks and will provide an idea of the age of the source of sedimentary detritus; hence establishing a maximum age for the sedimentary rock. In some cases, particularly in sedimentary rocks derived from volcanic rocks, the ages may be fairly close. Another possibility is the dating of cementing (authigenic) minerals within the sedimentary rocks ... a little more difficult, but under the right circumstances, possible.

Yeah... that's pretty generic.So much so that I don't really know where to start.Maybe first, I should say that most marble is not of igneous origin. It is a metamorphosed limestone for the most part. Oh, there are some carbonatite magmas that might be considered marble if recrystallized, but they are not very common.But a couple of answers to your basic question.We can infer the sedimentary origin of rocks in numerous ways and here are a few:-- by seeing transitional materials from unconsolidated sand to the hardest quartzite in the geological record.-- by seeing certain textures and forms that are formed during erosion and transport, such as rounding of grains or formation of cross-beds in both unconsolidated and lithified versions.-- by observing fossils being deposited and eventually completely permineralized with progressive lithification.I'm sure that there are many other lines of evidence and some will probably be given in future posts, but I'm not sure that the synthetic formation of rock is of any relevance.

Well, sensu stricto, a man-made rock is not a rock. But disregarding that for the time being, I see no reason why one could not form a 'rock' in short order by compression and dewatering.The problem is that there are many sub-processes going into the single process of lithification. It is an ongoing process that starts with deposition and may continue for a billion years.One question is, when do you have a rock? Are layers of cohesive clays on a lake bottom a rock? Are lightly cemented sands near a hot spring a rock? Is the slightly welded ash of a volcanic eruption a rock? Are tufa mounds in a saline lake composed of rock?We know that older rocks tend to be harder. So, is that process of hardening part of lithification?So, it's all subjective, IMHO. What is the problem with rapid lithification? What is the problem with slow, progressive lithification?

It all started with Hutton when he noticed that the soil in his fields was slowly creeping toward the stream and then carried away. He wondered why there was still soil in his fields after hundreds of years. That's when he realized that there are slow processes and time has a very long dimension.Basically, the things we see going on very slowly today produce features that we see exactly duplicated in the geological record, top to bottom. Looking at how long it takes to create some deposits, very long ages are understood.Beyond that, yes, absolute ages derived from various clocks, as Dr. A has mentioned, tell us the actual amounts of time involved. No, that just indicate a sudden change of depositional environments.

Actually, it is an arch. Because the sediments are bowed upward, erosion has removed some of the post-Ordovician rocks. Think of it as a broad anticline or a dome. I'm not sure what this principle is. This sentence does not track with what you are saying below. You just said they were exposed by erosion and they are quite extensive. I don't see why. Why can't you have a lot of events over millions of years? This isn't what you said above. Please explain. How is tectonism the cause of erosion? Do you think there could be more than one tectonic event? Again, you just said that the erosion between layers is extensive and caused by warping. This is a confusing post. There is a major unconformity in the section shown at the base of the Cretaceous. This indicates an erosional event after the Palezoic rocks were laid down, deformed and eroded, but before the Cretaceous rocks.

Faith, you are leaping into a complex subject without any preparation. Starting at the end of your post: First of all, the geological map and your cross-section are not indexed to each other.The cross section is on a completely different scale encompassing only the Carolina Thrust Belt on the very eastern edge of Tennessee. The map shows that as you go farther west into Tennessee, you get less and less disturbance from the Appalachian mountain building event. For instance, the large dome I referenced in my last post does not even show up on the cross section you present.And, no, there is not just one erosional event. For instance, the Cambrian rocks depicted on the geological map include arkoses which are derived from erosion of granitic basement rocks of the Precambrian. Furthermore there is a gap in the record between the Pennsylvanian rocks and the Cretaceous rocks in western Tennessee. And then, of course, there are other minor unconformities within the section that do not show up on a map of this scale. I will try to find a strat section that shows more, but most of the diagrams I find are insanely detailed and not appropriate for a discussion like this.As usual, the picture is a lot more complex than YECs would like.Perhaps more later. I have a little work to do.

Okay, so we have to exclude the rest of the state in order to prove your point.However, I still don't see the disconcert over a section of geology in which there happens to be little erosion. So what if sedimentation is continuous for most of the Paleozoic Era? There was pretty obviously some erosion before the Cambrian and certainly some prior to the Cretaceous Period. All that is in addition to the modern erosional surface on which we live.Your scenario of one erosional surface in the history of the earth simply does not work.ETA: If Percy feels that we are getting off topic I am not going to pursue this any further. Edited by edge, : No reason given.

I am far from expert on the geology of the state, but everything about it negates the premise that Faith has adopted. The fact is that the thrust belt shown in the cross section occurred in the mid-Paleozoic and did not affect the Pennsylvanian and later rocks. Not only that, but the Cretaceous rocks shown on the map are more related to development of the Mississippi Embayment in Mesozoic time. That's at least two major tectonic events prior to the time that Faith thinks all deformation occurred (that would be after all sedimentary rocks were deposited). And I'm not even getting into the Precambrian geology.

Okay, then, prove that the theory is wrong. Prove that there is another origin for arkose than erosion of a crystalline granitic basement rock. Maybe the origin is from space, for instance. Then prove to us that it doesn't work. Give us something better. At present, all we have is the YEC say-so that it's wrong, wrong, wrong...

You have been shown the evidence of buried topography below the Ordovician (IIRC) with valleys and ridges and a typical drainage pattern in a previous thread and you simply denied it. What's obvious is that you have no answer but denial.

So, you really think that groundwater flows in rivers and tributaries just as surface water does?Okaaaaay, and this is based on what kind of experience or training? To you? Nothing. Because it ... isn't ?Again, where do you get this idea? Probably because they are not as smart as you.

Sorry, not getting your problem.Are you really saying that it's all wrong because Faith disagrees? All I see from you is assertions based on you hiding behind the Bible.

To a YEC, everything is a mystery...