TY - JOUR
T1 - Deciphering long-term coastal dynamics using IR-RF and ESR dating
T2 - a case study from Médoc, south-west France
AU - Kreutzer, Sebastian
AU - Duval, Mathieu
AU - Bartz, Melanie
AU - Bertran, Pascal
AU - Bosq, Mathieu
AU - Eynaud, Frédérique
AU - Verdin, Florence
AU - Mercier, Norbert
N1 - Funding Information:
We are thankful to Nathan Brown and Frank Preusser for constructive and helpful comments on our manuscript. The authors are also thankful to Mélanie Saint-George and Virginie Moineau for carrying out the sample preparation in the luminescence lab in Bordeaux. Yannick Lefrais is thanked for conducting the EDX measurements. Part of the work for this study was carried out in the framework of the project Inter-LabEx LaScArBx/COTE (2013–2015) coordinated by FV (LaScArBx) and FE (COTE), supported by the ANR ( ANR-10-IDEX-03-02 ). The ESR dating study has been funded by the Australian Research Council Future Fellowship grant FT150100215 . SK received financial support from the LaScArBx. LaScArBx is a research programme supported by the ANR ( ANR-10-LABX-52 ).
Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/10/1
Y1 - 2018/10/1
N2 - A proper understanding of local palaeoenvironmental histories is an iterative process. Previously settled interpretations suddenly demand a reconsideration triggered by findings from sites not accessible before. The coastline of the Médoc area in south-west France faced considerable recent erosion, providing new valuable insights into the history of the local Holocene and Pleistocene deposits; mainly of estuarine, lacustrine and aeolian origin. In the framework of the project LITAQ for reconstructing the coastal history of the Aquitaine basin, new recently outcropped sediment profiles have been investigated. To establish the chronological framework, for the first time optically stimulated luminescence (OSL) on quartz, infrared radiofluorescence (IR-RF) on K-feldspar were applied in conjunction with multiple-centres electron spin resonance (ESR) dating on quartz. Our approach combines routine luminescence dating application with methodological investigations, with a focus on IR-RF and ESR dating. IR-RF and ESR ages are consistently older than the OSL ages, presumably due to insufficient bleaching, however, they are consistent within 2σ. Our study confirms that the investigated area is covered by Holocene sands, following Pleistocene colluvial and aeolian sandy deposits mainly deposited in a periglacial context during MIS 8 and MIS 10. The base of the profiles appears to consist of interglacial estuarine deposits, probably from the Holsteinian (MIS 11), supporting the theory of a progressive replacement of a tide-influenced marsh by a peaty fresh-water pond during that period. Finally, IR-RF and multiple-centres ESR dating can be considered as valuable tools to decipher Middle Pleistocene landscape dynamics
AB - A proper understanding of local palaeoenvironmental histories is an iterative process. Previously settled interpretations suddenly demand a reconsideration triggered by findings from sites not accessible before. The coastline of the Médoc area in south-west France faced considerable recent erosion, providing new valuable insights into the history of the local Holocene and Pleistocene deposits; mainly of estuarine, lacustrine and aeolian origin. In the framework of the project LITAQ for reconstructing the coastal history of the Aquitaine basin, new recently outcropped sediment profiles have been investigated. To establish the chronological framework, for the first time optically stimulated luminescence (OSL) on quartz, infrared radiofluorescence (IR-RF) on K-feldspar were applied in conjunction with multiple-centres electron spin resonance (ESR) dating on quartz. Our approach combines routine luminescence dating application with methodological investigations, with a focus on IR-RF and ESR dating. IR-RF and ESR ages are consistently older than the OSL ages, presumably due to insufficient bleaching, however, they are consistent within 2σ. Our study confirms that the investigated area is covered by Holocene sands, following Pleistocene colluvial and aeolian sandy deposits mainly deposited in a periglacial context during MIS 8 and MIS 10. The base of the profiles appears to consist of interglacial estuarine deposits, probably from the Holsteinian (MIS 11), supporting the theory of a progressive replacement of a tide-influenced marsh by a peaty fresh-water pond during that period. Finally, IR-RF and multiple-centres ESR dating can be considered as valuable tools to decipher Middle Pleistocene landscape dynamics
KW - ESR
KW - IR-RF
KW - Middle Pleistocene
KW - Médoc
KW - OSL
UR - http://www.scopus.com/inward/record.url?scp=85054029717&partnerID=8YFLogxK
U2 - 10.1016/j.quageo.2018.09.005
DO - 10.1016/j.quageo.2018.09.005
M3 - Article
SN - 1871-1014
VL - 48
SP - 108
EP - 120
JO - Quaternary Geochronology
JF - Quaternary Geochronology
ER -