RT info:eu-repo/semantics/article T1 Reconstructing the sedimentary history of Lezetxiki II cave (Basque Country, northern Iberian Peninsula) using micromorphological analysis A1 Arriolabengoa, Martín . A1 Iriarte Avilés, Eneko A1 Aranburu, Arantza . A1 Yusta, Iñaki . A1 Arnold, Lee J. . A1 Demuro, Martina . A1 Arrizabalaga, Alvaro . K1 Cave sedimentary processes K1 Sedimentary petrology K1 Single-grain dating K1 Paleoenvironmental changes K1 Lezetxiki II cave K1 Paleontology K1 Paleontología AB Micromorphological analysis is an invaluable research tool for reconstructing detailed depositional and post-depositional processes of cave infill sequences and for providing paleoenvironmental insight. In this work, we present the results of a micromorphological and mineralogical study of the sedimentary sequence at the Lezetxiki II cave (northern Iberian Peninsula). The cave forms part of the Lezetxiki archaeological complex which has yielded early Middle Palaeolithic tools and archaic human remains. We have identified three main clastic sedimentary processes as being significant at Lezetxiki II: 1) fluviokarst or runoff processes, which are characterised by yellow sandy illite-rich microfacies; 2) infiltration processes, which produce a massive red silty-clay vermiculite-rich microfacies; and 3) inwash processes, which generate a reworked illite and vermiculite rich silty sand microfacies. The most common post-depositional processes observed are calcite precipitation infilling pore spaces, and compression structures derived from specific vertical loading events. In order to improve the chronological framework of the sedimentary sequence at Lezetxiki II, we have revised previous radiometric and relative dating results from faunal and archaeological remains and have dated the lowermost stratigraphic level using single-grain thermally-transferred optically-stimulated luminescence dating. Sedimentation at the Lezetxiki II cave started during Marine Isotope Stage (MIS) 7 through fluviokarst processes. We interpreted that runoff prevailed during MIS 6, while soil infiltration processes became more significant towards the MIS 5 optimum. Gradually, inwash processes prevailed over infiltration until the end of the interglacial phase. During the following glacial phases, runoff and erosion dominated but were subsequently replaced by inwash processes during MIS 1. PB Elsevier SN 0037-0738 YR 2018 FD 2018-10 LK http://hdl.handle.net/10259/4808 UL http://hdl.handle.net/10259/4808 LA eng NO PALEOGATE project, funded by the Spanish Ministry of Economy and Competitiveness (HAR2014-53536-P) as well as the US14/16 project funded by the University of the Basque Country and Basque Coast Geopark, and Basque Government (IT1029-16-GBV6). We would also like to thank Tim Nicholson for his work in translating and editing different versions of the English text. Additional financial support for this research was provided by Australian Research Council (ARC) Future Fellowship project FT130100195, ARC Discovery Early Career Researcher Award DE160100743 DS Repositorio Institucional de la Universidad de Burgos RD 28-mar-2024