An integrated FT/Raman/EMP/XRD-investigation of the fission-track and radiation-damage records in natural titanites from the Kontinentale Tiefbohrung (KTB)

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The fission-track method offers the advantage that large sample sets can be investigated at low cost. Dense regional sampling and age-vs.-elevation profiles allow to distinguish intrusive and tectonic events and to estimate the timing, rate and magnitude of uplift. Track-length measurements provide palaeotemperature- information in addition to the fission-track age. The Kontinentale Tiefbohrung demonstrates how the closure-temperature of titanite allows to identify events not registered by other geochronometers. Research has demonstrated that several factors affect the etching and annealing behaviour of fission tracks in titanite; the results are however difficult to integrate because the samples are often not wellcharacterised in terms of composition and self-irradiation damage; nor are their effects quantified in terms of practical use in geological applications. Geologists have to accept the limited guarantee that the ζ-calibration offers and must disregard the palaeotemperature-information that the track-length distribution can provide. The proposed research aims to investigate the factors affecting age-determinations and palaeotemperature-estimates based on fission tracks in titanite. Its strength lies in the combination of annealing experiments, the analysis of borehole samples and in the full characterisation of the chemical composition, crystal structure and self-irradiation damage of the samples. This must allow us to propose more accurate dating methods and to develop a method for temperature-time path modelling similar to that for apatite.