<abstract xmlns="http://www.w3.org/1999/xhtml">Optical dating of earthquake related sediments were investigated including one modern sample and three samples from a trench excavated across the 1985 Ms7.4 Wuqia Earthquake surface rupture. The results indicated that equivalent dose (De) values vary with grain size and the method used for De determination. The residual dose of the modern sample is 0.1 ka (
<inline-formula><alternatives><inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/j_geochr-2015-0075_eq_001.png"></inline-graphic><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mtable columnalign="" rowspacing="4pt" columnspacing="1em"><mtr><mtd><msubsup><mn>0.2</mn><mrow class="MJX-TeXAtom-ORD"><mo>−</mo><mn>0.1</mn></mrow><mrow class="MJX-TeXAtom-ORD"><mo>+</mo><mn>0.2</mn></mrow></msubsup></mtd></mtr></mtable></math><tex-math>$\begin{array}{}
0.2_{-0.1}^{+0.2}
\end{array} $</tex-math></alternatives></inline-formula> Gy) for the quartz single grain measurements. Only 1.5–3.6% of the grains have a detectable OSL signal. Single grain quartz ages are similar to the expected ages. Fine grain quartz results overestimate the De values and are much older than single grain quartz and coarse grain quartz small aliquot standardized growth curve (SA-SGC) ages. Single grain quartz OSL dating may be optimal for dating earthquake related deposits, but SA-SGC can save measurement time and has potential for dating some poorly bleaching samples.</abstract>

Optical dating of earthquake related sediments were investigated including one modern sample and three samples from a trench excavated across the 1985 Ms7.4 Wuqia Earthquake surface rupture. The results indicated that equivalent dose (De) values vary with grain size and the method used for De determination. The residual dose of the modern sample is 0.1 ka (
0.2−0.1+0.2$\begin{array}{}
0.2_{-0.1}^{+0.2}
\end{array} $ Gy) for the quartz single grain measurements. Only 1.5–3.6% of the grains have a detectable OSL signal. Single grain quartz ages are similar to the expected ages. Fine grain quartz results overestimate the De values and are much older than single grain quartz and coarse grain quartz small aliquot standardized growth curve (SA-SGC) ages. Single grain quartz OSL dating may be optimal for dating earthquake related deposits, but SA-SGC can save measurement time and has potential for dating some poorly bleaching samples.

Coarse versus fine-grain quartz optical dating of the sediments related to the 1985 Ms7.1 Wuqia earthquake, northeastern margin of the Pamir salient, China

Guangdong Provincal Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering

Geochronometria

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

Optical dating of earthquake related sediments were investigated including one modern sample and three samples from a trench excavated across the 1985 Ms7.4...

Coarse versus fine-grain quartz optical dating of the sediments related to the 1985 Ms7.1 Wuqia earthquake, northeastern margin of the Pamir salient, China

Pubblicato online: 23 nov 2017

Pagine: 299 - 306

Ricevuto: 31 gen 2016

Accettato: 19 mag 2017

DOI: https://doi.org/10.1515/geochr-2015-0075

Parole chiave
paleo-earthquake, quartz OSL dating, single grain, coarse grain

© 2016 H. Yang.

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

Coarse versus fine-grain quartz optical dating of the sediments related to the 1985 Ms7.1 Wuqia earthquake, northeastern margin of the Pamir salient, China

Pubblicato online: 23 nov 2017

Pagine: 299 - 306

Ricevuto: 31 gen 2016

Accettato: 19 mag 2017

DOI: https://doi.org/10.1515/geochr-2015-0075

Parole chiavepaleo-earthquake, quartz OSL dating, single grain, coarse grain

© 2016 H. Yang.

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

Parole chiave
paleo-earthquake, quartz OSL dating, single grain, coarse grain