<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>The precise chronology of the fluvial terraces of the Yellow River in China is essential to understand its geomorphological evolution history. More terrace ages are needed for the correlation of the terraces along the river and the construction of the longitudinal profile. In this study, seven terraces (T1–T7) in the Heiyukou area of the Jinshaan Canyon of the river were identified and were sampled for optical dating. The reliability of the ages was evaluated on the bases of bleachability, comparison of optical ages on fine and coarse grains, stratigraphic consistency of OSL ages, age distribution and geomorphological setting. The results show that the paired T2 terrace was formed at 72 ± 3 ka, and the T4, T5 strath terraces were dated to 108 ± 4 and >141 ± 4 ka, respectively. The ages for the samples from T6 and T7 were significantly underestimated, and the ‘infinitely old’ pre-Quaternary Red-Clay sample on the T7 terrace was dated to 134 ± 6 ka. The long-term river incision rates were calculated to be &lt;0.36, 0.34 and 0.18 mm/a for at least the past 141, 108 and 72 ka, respectively, which also reflect the uplift rates of the Ordos plateau. The implication for dating terrace deposits is that terraces should be systemically sampled and dated using both fine and coarse grain fractions. The reliability of the ages obtained for high terraces should be evaluated using a relative chronology of dated samples on a case-by-case basis, if no independent numerical age controls are available.</p>
</abstract>

The precise chronology of the fluvial terraces of the Yellow River in China is essential to understand its geomorphological evolution history. More terrace ages are needed for the correlation of the terraces along the river and the construction of the longitudinal profile. In this study, seven terraces (T1–T7) in the Heiyukou area of the Jinshaan Canyon of the river were identified and were sampled for optical dating. The reliability of the ages was evaluated on the bases of bleachability, comparison of optical ages on fine and coarse grains, stratigraphic consistency of OSL ages, age distribution and geomorphological setting. The results show that the paired T2 terrace was formed at 72 ± 3 ka, and the T4, T5 strath terraces were dated to 108 ± 4 and >141 ± 4 ka, respectively. The ages for the samples from T6 and T7 were significantly underestimated, and the ‘infinitely old’ pre-Quaternary Red-Clay sample on the T7 terrace was dated to 134 ± 6 ka. The long-term river incision rates were calculated to be <0.36, 0.34 and 0.18 mm/a for at least the past 141, 108 and 72 ka, respectively, which also reflect the uplift rates of the Ordos plateau. The implication for dating terrace deposits is that terraces should be systemically sampled and dated using both fine and coarse grain fractions. The reliability of the ages obtained for high terraces should be evaluated using a relative chronology of dated samples on a case-by-case basis, if no independent numerical age controls are available.

Luminescence Chronology of the Yellow River Terraces in the Heiyukou Area, China, and Its Implication for the Uplift Rate of the Ordos Plateau

MOE Laboratory for Earth Surface Processes

Department of Geography, College of Urban and Environmental Sciences

Geochronometria

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The precise chronology of the fluvial terraces of the Yellow River in China is essential to understand its geomorphological evolution history. More terrace...

Luminescence Chronology of the Yellow River Terraces in the Heiyukou Area, China, and Its Implication for the Uplift Rate of the Ordos Plateau

Pubblicato online: 31 dic 2021

Pagine: 325 - 338

Ricevuto: 15 feb 2019

Accettato: 29 ott 2019

DOI: https://doi.org/10.2478/geochr-2020-0008

Parole chiave
Luminescence dating, systematic sampling, infinitely old sample, evaluation of age reliability, Yellow River terraces

© 2019 Yan-Yan Yan et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Luminescence Chronology of the Yellow River Terraces in the Heiyukou Area, China, and Its Implication for the Uplift Rate of the Ordos Plateau

Pubblicato online: 31 dic 2021

Pagine: 325 - 338

Ricevuto: 15 feb 2019

Accettato: 29 ott 2019

DOI: https://doi.org/10.2478/geochr-2020-0008

Parole chiaveLuminescence dating, systematic sampling, infinitely old sample, evaluation of age reliability, Yellow River terraces

© 2019 Yan-Yan Yan et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Parole chiave
Luminescence dating, systematic sampling, infinitely old sample, evaluation of age reliability, Yellow River terraces