A feasibility study on the application of luminescence dating for quartz from different rock types as a thermochronometer

Thermal ages (e.g. fission track, Ar/Ar and U-Th/He ages) are important to understand mountain building activities within the upper crust. In order to understand the uplift history of Taiwan, researchers are looking for the applicability of thermal ages from fairly low cooling temperatures by using luminescence dating methods. The low-temperature-involved recent past is an area of great interest. Since the reliability of the luminescence dating method is sample dependent, this ongoing study starts with checking relevant characteristics of the luminescence properties from appropriate minerals (e.g. quartz). The samples for this study were collected from the Central Range in Taiwan. Sampling locations were chosen to cover various altitudes across the Central Range from two different rock types: 1) cherty-marble and 2) meta-sandstone. This sampling strategy is intended to decipher rock dependent variation because cherty-marble has not undergone as much stress as meta-sandstone. We compare luminescence behaviors of quartz between samples from cherty-marble and meta-sandstone. The equivalent doses were determined by conventional single aliquot regenerative-dose (SAR) protocol and SAR isothermal thermoluminescence (ITL) protocol. Results suggest that the preheat process may not be applicable for quartz from both cherty-marble and meta-sandstone of Taiwan. The SAR ITL protocol without preheat processes was applied successfully on the sample for such an approach. Although our current results of ITL seem promising, further and detailed luminescence characteristics of ITL should be examined before the feasibility is finally proposed. (C) 2012 Elsevier B.V. All rights reserved.