Alpha-decay damage in minerals of the pyrochlore group

摘要: X-ray diffraction analysis and transmission electron microscopy have been used to study the effects of alpha-decay damage in pyrochlore group minerals, characterized by general formula A1−mB2O6(O,OH,F)1−n·pH2O. As defined XRD intensity ratio I/I0, both saturation dose (for which I/I0=0.1−0.0) signifies initial loss crystallinity I/I0=1.0−0.8) increase as a function geologic age. The is attributed annealing isolated alpha-recoil tracks back original crystalline structure. calculated mean lives, τa, on order 108 years. In contrast, minerals remain (e.g., uraninite, UO2) despite doses up 1018 alpha-events/mg track lives ≈104 years (Eyal Fleischer 1985).