11:00 AM - 1:00 PM
[SCG42-P07] Estimation of emergence age using feldspar OSL dating: case studies in the Noto Peninsula and the Oi River
Keywords:OSL dating, feldspar, emergence age
Optically stimulated luminescence (OSL) dating method on feldspar is useful to date sediments on geomorphological time scale (103-105 years). In this presentation, we present the case studies for marine terraces in the Noto Peninsula and abandoned river valleys along the Oi River, for which the emergence ages were estimated by using feldspar OSL dating. This study was carried out as a part of the “establishment of advanced technology for estimation of uplift rates using emergence ages of emergent landforms” project [1].
Noto Peninsula: Pleistocene marine terraces formed at several stages are widely distributed in the Noto Peninsula, Ishikawa. Thus, we can verify the applicability of feldspar OSL dating method to the marine sediments older than 100,000 years. We applied post-IR IRSL (pIRIR) dating to the marine terrace correlated to marine isotope stage 7 [2]. The sediments were divided into the covering layers and marine deposits based on observations of the sedimentary facies. In this presentation, we will present the emergence age constrained from dating results of a loamy sample from the covering layers and two sand samples from the marine sediments.
Oi River: In areas with poor distribution of fluvial terraces, such as southwest Japan, it is expected to estimate uplift rates based on the depositional ages of the channel sediments in an abandoned river valley around a cutoff spur and the relative elevations [3]. We verified the potential of this method along the Oi River in the Akaishi Range where river valleys around a cutoff spur [4] and fluvial terraces were abundantly identified. We applied pIRIR dating to the borehole core drilled at the abandoned river valley around a cutoff spur ~200 m above the present riverbed. The borehole core was divided into artificial, colluvial, fluvial deposits and bedrocks. In this presentation, we will present the emergence age and uplift rates estimated from the OSL dating results of two mud samples from the colluvial deposits and two sand samples from the fluvial sediments.
This study was funded by the Ministry of Economy, Trade and Industry (METI), Japan as part of its R&D supporting program titled “Establishment of Advanced Technology for Evaluating the Long-term Geosphere Stability on Geological Disposal Project of Radioactive Waste (JPJ007597) (Fiscal Years 2020-2021)”.
[1] JAEA and CRIEPI (2021). “Establishment of Advanced Technology for Evaluating the Long-term Geosphere Stability on Geological Disposal Project of Radioactive Waste” Report, 317p.
[2] Koike and Machida (2001). University of Tokyo Press, 122p.
[3] Yasue et al. (2014). Jour. Geol. Soc. Japan, 120, 12, 435-445.
[4] Takatori et al. (2013). JAEA-Data/Code 2012-028, 15p.
Noto Peninsula: Pleistocene marine terraces formed at several stages are widely distributed in the Noto Peninsula, Ishikawa. Thus, we can verify the applicability of feldspar OSL dating method to the marine sediments older than 100,000 years. We applied post-IR IRSL (pIRIR) dating to the marine terrace correlated to marine isotope stage 7 [2]. The sediments were divided into the covering layers and marine deposits based on observations of the sedimentary facies. In this presentation, we will present the emergence age constrained from dating results of a loamy sample from the covering layers and two sand samples from the marine sediments.
Oi River: In areas with poor distribution of fluvial terraces, such as southwest Japan, it is expected to estimate uplift rates based on the depositional ages of the channel sediments in an abandoned river valley around a cutoff spur and the relative elevations [3]. We verified the potential of this method along the Oi River in the Akaishi Range where river valleys around a cutoff spur [4] and fluvial terraces were abundantly identified. We applied pIRIR dating to the borehole core drilled at the abandoned river valley around a cutoff spur ~200 m above the present riverbed. The borehole core was divided into artificial, colluvial, fluvial deposits and bedrocks. In this presentation, we will present the emergence age and uplift rates estimated from the OSL dating results of two mud samples from the colluvial deposits and two sand samples from the fluvial sediments.
This study was funded by the Ministry of Economy, Trade and Industry (METI), Japan as part of its R&D supporting program titled “Establishment of Advanced Technology for Evaluating the Long-term Geosphere Stability on Geological Disposal Project of Radioactive Waste (JPJ007597) (Fiscal Years 2020-2021)”.
[1] JAEA and CRIEPI (2021). “Establishment of Advanced Technology for Evaluating the Long-term Geosphere Stability on Geological Disposal Project of Radioactive Waste” Report, 317p.
[2] Koike and Machida (2001). University of Tokyo Press, 122p.
[3] Yasue et al. (2014). Jour. Geol. Soc. Japan, 120, 12, 435-445.
[4] Takatori et al. (2013). JAEA-Data/Code 2012-028, 15p.