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The aim of this study is to constrain a meta-morphic history using EMP dating of monazite on example of the Tatra Mts.
We compare our results with those obtained from single-grain, cathodoluminescence-controlled, U-Pb dating of zircons (Poller et al., 2000, Poller and Todt, 2000).
We apply the U-Th-total Pb electron microprobe chemical dating method to a uraninite crystal from a ca.
18.3 Ma dike of the Mugu granite from the Upper Mustang region of central Nepal.
), which can contain very high concentrations of radiogenic Pb after only a few million of years of U and Th decay.
Electron microprobe chemical dating yields results that typically will be an order of magnitude less precise than conventional dates: in the specific case of the Mugu granite, single point chemical dates each have ca. However, the mean chemical date of 15 point analyses of the crystal we study has a 2SE (2 standard error) uncertainty of ca.
As the extraction temperature is increased, deeper or more strongly held argon is released from the mineral lattice.
The process can reveal not only an original cooling age for disturbed samples, but often (i) the age of the later event causing the disturbance, (ii) argon diffusion characteristics of the sample and (iii) the thermal history of the later event.