40Ar/39Ar Dating: Principles, Techniques, and Applications in Orogenic Terranes
The 40 Ar/39Ar dating technique is a recently developed analytical variation of the conventional K-Ar method. It has greatly enhanced the general applicability of K-Argeochronology because it has the ability to distinguish between: (1) samples which have lost a component of radiogenic argon since their initial crystallization, (2) samples which have remained closed systems with respect to potassium and argon since their initial crystallization, and, (3) samples which contain a component of extraneous argon of non-atmospheric 40 Ar/39 Ar ratio. In principle this potential has not yet been fully realized. However, basic systematics of the technique are still in the developmental stages and initial results are encouraging.
KeywordsBlue Ridge Radiogenic Argon Release Spectrum Argon Loss Retrograde Alteration
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