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Zircon is one of the most useful minerals used to unravel the Earth’s history recorded in rocks. After the success of etching fission tracks in zircon (Fleischer et al. 1964; Naeser 1969; Krishnaswami et al. 1974), early studies focused primarily on dating young volcanic horizons for stratigraphic purposes (e.g., Naeser et al. 1973; Hurford et al. 1976; Seward 1979; Gleadow 1980; Kowallis et al. 1986; Kohn et al. 1992). Subsequently, fission-track analysis of zircon has been extensively employed, along with other radiometric dating methods, such as U/Pb and (U-Th)/He techniques (e.g., Davis et al. 2003; Reiners 2005), to understand the thermochronology of rocks in a variety of geological settings: i.e., thermal history analysis of basement rocks for orogenic studies (e.g., Zeilter et al. 1982; Hurford 1986; Kamp et al. 1989; Sorkhabi 1993; Seward and Mancktelow 1994; Hasebe and Tagami 2001; Spikings et al. 2001), thermochronology using detrital zircon grains in sedimentary rocks for provenance analysis and thermal history analysis in or near faults, which will be highlighted below.
In this present chapter, the thermal sensitivity of the zircon fission-track thermochronometry is reviewed in the context of laboratory and field studies. Then, laboratory procedures of the zircon fission-track analysis using the external detector method are outlined, as practiced in the fission-track laboratory of Kyoto University. For basic fundamentals of these fission-track analyses, including data analysis and graphical displays, see the chapter by Tagami and O’Sullivan (2005). Finally, as an example of recent geological applications of the technique, the results of zircon fission-track analysis of the Nojima fault zone, Japan, are presented. These rocks were the target of systematic drilling of an active fault system using five boreholes and a trench. Applications to other geological settings and the …