Pleistocene coralline algal buildups on a mid-ocean rocky shore – Insights into the MIS 5e record of the Azores

Located on the northern coast of Santa Maria Island (Azores Archipelago, central North Atlantic), the Lagoinhas section preserves a carbonate buildup correlated with Marine Isotope Substage (MIS) 5e, the warmest interval of the Last Interglacial. The buildup is formed mainly by crustose coralline algae (CCA) identified as Spongites sp., and some subordinate crusts of Lithophyllum sp. and Neogoniolithon sp., as well as cf. Titanoderma sp. Extant CCA buildups are not recorded in the archipelago. Herein, we describe in detail the morphological and taphonomical features of the Lagoinhas CCA buildup and interpret the environment in which it grew. Additionally, this buildup is compared with another of similar age, exposed in the Prainha-Praia do Calhau section on the island's opposite southern coast. The hydrodynamic regime appears to play a crucial role in the development of Azorean CCA buildups during the MIS 5e. We thank Direccao Regional da Ciência e Tecnologia (Regional Government of the Azores), FCT (Fundação para a Ciência e a Tecnologia) of the Portuguese Government, and Camara Municipal de Vila do Porto for financial support. We also acknowledge the field assistance of Camara Municipal de Vila do Porto. We are grateful to the organizers and participants of the 16 editions of the International Workshop Palaeontology in Atlantic Islands who helped with fieldwork (2002 2020). A.C.R. was supported by a grant SFRH/BPD/117810/2016 from FCT (Fundação para Ciência e Tecnologia), Portugal. S.P.A. and R.S.R. acknowledge their research contracts (IF/00465/2015 and IF/01641/2015, respectively) funded by Fundação para a Ciência e a Tecnologia (FCT). C.S.M. is benefiting from a PhD grant M3.1.a/F/100/2015 from Fundo Regional para a Ciência e Tecnologia (FRCT). This work was supported by FEDER funds through the Operational Programme for Competitiveness Factors -COMPETE, by Portuguese National Funds through FCT under the projects UID/BIA/50027/2013, UID/BIA/00329/2013-2023, POCI-01-0145-FEDER-006821, PLATMAR (PTDC/GEO-GEO/0051/2014) and under DRCT-M1.1.a/005/Funcionamento-C-/2016 (CIBIO-A) project from FRCT, and by FEDER funds (in 85%) and by funds of the Regional Government of the Azores (15%) trough Programa Operacional Acores 2020, in the scope of the projects "AZORESBIOPORTAL -PORBIOTA": ACORES-01-0145FEDER-000072 and VRPROTO -Virtual Reality PROTOtype: the geological history of "Pedra-que-pica": ACORES-01-0145-FEDER000078. A.U. benefited from additional support by the Jagiellonian University. info:eu-repo/semantics/publishedVersion