Millennial-timescale climate change over the last 800 kyrs evidenced by magnetic, colorimetric and ATR-FTIR data from the Suhia Kladenetz quarry loess-paleosol sequence (Pleven, Bulgaria)

• Main Authors: Laag, Christian, Lagroix, France, Guyodo, Yohan, Jordanova, Diana, Jordanova, Neli, Ishlyamski, Daniel, Georgieva, Bozhurka, Saulnier-Copard, Ségolène, Chapkanski, Stoil, Moine, Olivier, Antoine, Pierre
• Other Authors: Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), National Institute of Geophysics, Geodesy and Geography (NIGGG), Bulgarian Academy of Sciences (BAS), Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), ARCHEORIENT - Environnements et sociétés de l'Orient ancien (Archéorient), Université Lumière - Lyon 2 (UL2)-Centre National de la Recherche Scientifique (CNRS)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology; [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy; [SHS.GEO]Humanities and Social Sciences/Geography; ice core; NGRIP
• Online Access: https://hal.science/hal-04076238

International audience Eastern European loess-paleosol sequences (LPS) are excellent archives of past climate change. Millennial-timescale climate change is successfully evidenced in loess of the last and penultimate glacial periods. However, study designs with similar or lower sampling resolution strategies and/or single proxy investigations do not favor their identification for earlier glacials, which are generally scarcer, thinner and characterized by lower sedimentation rates.The high-sampling resolution multi-proxy study presented here demonstrates the first evidence of millennial-timescale climate change for periods older than MIS6 archived in an Eastern European LPS. The Suhia Kladenetz 27 m long profile was sampled continuously at a 2 cm resolution for bulk sediment. Magnetic and colorimetric measurements are performed on all samples. ATR-FTIR data is acquired at the same resolution through loess units and at a 12 cm interval elsewhere, while grain size analyses are conducted continuously at a 12 cm interval. Rock magnetic data and microscopic observations, from our previous work, characterized a 20-cm-thick outcropping tephra in the MIS6 loess unit and identified several cryptotephras. Moreover, a correlative age model demonstrating that the LPS covers the last ~800 kyrs allowed to provide age estimates for the tephra and cryptotephras and thereafter to deduce their likely volcanic sources.The integrated age model in combination with high-resolution colorimetry-based estimates of goethite and hematite concentrations, and clay mineralogy highlight a cyclicity undoubtedly driven by climate change within interstadials/stadials as shown by correlations with the NGRIP δ18O ice core records for the last glacial/interglacial cycle.