>> Question 1: Is Carbon-14 continually being formed by natural
>> processes, or did all the C-14 that ever existed in nature get
>> formed "in the beginning"? If it gets continually formed in
>> nature then that would not harm an old-earth argument.
As others have noted, it is formed in the upper atmosphere. According
to tree-ring calibrations, the formation rate varies as much as 10-15%
from the current value (although the decay rate is constant).
>> Question 2: You talked about the ability or inability of certain
>> isotopes or elements to be part of a certain type of crystalline
>> lattice structure when it was formed. Would the type of lattice
>> structure being formed in the first place be in any way dependant
>> on the earth's atmospheric conditions at the time of formation?
>> For example, if the 02 content of the atmosphere was 30-35% and
>> the atmospheric pressure was 30-40 psia could that possibly have
>> an effect?
Almost impossible, I would think. Crystallization is controlled by
powerful electromagnetic forces at short distance, mild environmental
influences would be of no importance.
Another "assumption" creationists often mention about radioisotope
dating is that decay rates remain constant (Joe didn't raise this topic
though). Decay rates are controlled by strong nuclear forces inside
nuclei, that are very powerful and operate at very short distances.
Nuclei are insulated from outside effects by the surrounding cloud of
electrons. There are a few different modes of decay, some of which can
vary by as 1% under extreme conditions. I suspect the decays used in
dating have no measurable variation even under extreme environmental
effects.
>> Question 3: How bout giving us a lecture on the basics of
>> isochron dating. I've never heard of that before and would like
>> to know what it is and how it works.
Others have mentioned the isochron FAQ (mail me for a copy if you can't
access it on the web). Briefly, measurements are made on many different
minerals in a sample which contain the elements in question (usually
rubidium and strontium). If graphed in a certain way, the data points
will be on a straight line *if no contamination or leakage occurs*. The
angle of the line changes as the sample ages. You can think of it as a
simultaneous equation that not only gives the age of the sample, but
also the initial amounts of the minerals, so it gets around the
objection that the initial amount of the decay product has to be known.
-- Jim Foley Symbios Logic, Fort CollinsJim.Foley@symbios.com (303) 223-5100 x9765* 1st 1.11 #4955 * "I am Homer of Borg! Prepare to be...OOooooo! Donuts!!!"