Copy and paste this URL into your Address bar; I don't know how to post links:
http://www.answersingenesis.org/docs/3317.asp
Scientists are just people, and they tend to discard as irrelevant any "test" results or "control anomalies" which do not comport with their pre-formed conclusions. In fact, if one has a hand in assembling the data, a "scientific" projection can take any curve you like.
Ah, Thomas G. Barnes 1973 ICR technical monograph? An old chestnut... I'm surprised that YECs are still using it! One of the main reasons for rejecting the theory is that the earth's magnetic field periodically reverses itself (asrecorded in sea floor sedments), thus of course rendering any unidirectional extrapolation on field strength useless.
Here's a useful discussion on it.
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