Progress towards a polymineral single-aliquot OSL dating procedure

Area of Science:

• Geochronology
• Luminescence Dating
• Earth Sciences

Background:

• Standard single-aliquot regenerative-dose (SAR) procedures for quartz dating use a 'cutheat' distinct from the pre-heat.
• Previous research indicated that feldspar sensitivity changes can be corrected using SAR if the 'cutheat' equals the pre-heat.
• Dating polymineral samples often requires separate procedures for quartz and feldspar, complicating analysis.

Purpose of the Study:

• To test a modified SAR procedure capable of correcting sensitivity changes in both quartz and feldspar.
• To investigate the feasibility of a single, unified SAR protocol for polymineral samples.
• To evaluate different optical stimulation methods for improving luminescence dating accuracy and age range.

Main Methods:

• Implementation and testing of a single SAR procedure with identical 'cutheat' and pre-heat settings for both quartz and feldspar.
• Evaluation of sedimentary quartz response to the unified heating protocol.
• Assessment of various optical stimulation techniques, including infrared (IR)-stimulated signals within post-IR blue-stimulated sequences.

Main Results:

• The unified SAR procedure, with 'cutheat' equal to pre-heat, is effective for sedimentary quartz.
• This unified approach shows potential for measuring equivalent doses in mixed mineral samples (polymineral samples).
• Utilizing the post-IR blue-stimulated signal from feldspar, particularly the IR-stimulated component, extends the potential age range for feldspathic materials.

Conclusions:

• A single SAR procedure can be developed for dating both quartz and feldspar in polymineral samples, simplifying luminescence dating.
• The use of IR-stimulated signals in post-IR blue-stimulated sequences enhances the dating potential of feldspar-rich samples.
• The distinct signal characteristics of feldspar and quartz in mixed samples may allow for the extraction of individual mineral signals.