大连西海岸低地沉积环境特征及对气候环境指示意义OA

[Objective]The high-resolution climate reconstruction of Liaodong Peninsula is important for exploring the evolution of regional climate environment and high-quality development.The sedimentary environment of the Liaodong Peninsula is diverse and complex,studies on the types and sequence characteristics of sediments in differ-ent periods in small areas is lack.The aim of this study is to reconstruct the sedimentary environment and climate his-tory by studying the sediments of the west coast of Dalian.[Methods]By analyzing AMS14C dating,lithology,and geochemical elements of the Laoyuwo(LYW)section to reveal the evolution of sedimentary environment and paleo-climate of the region.[Results]The sediment is mainly composed of sand,silt,and gravel,which recorded sedimen-tary environment and paleoclimate evolution information from the Last Glacial Maximum(LGM)to the Middle Holo-cene(18 815-6 802 cal.a B.P.).The main chemical components in the profile are SiO2,Al2O3,K2O,and Fe2O3,the total content of which is 90.34%.The contents of major elements from large to small are SiO2>Al2O3>K2O>Fe2O3>Na2O>CaO>TiO2>MgO>P2O5>MnO.The sedimentary records shows that the region experienced a dry and cold alluvial(18.8 cal.ka B.P.-late LGM),slightly warm and humid coastal intertidal(18.8-16.0 cal.ka B.P.),warm and humid coastal subtidal(18.8-16.0 cal.ka B.P.),warm and humid coastal subtidal(16.0-11.7 cal.ka B.P.),warmest and wettest coastal salt marsh(11.7-6.8 cal.ka B.P.),and dry and cold fluvial environment(6.8-0 cal.ka B.P.).The highest sea level around 6.8 cal.ka B.P.and the rapid climatic events during Younger Dryas(DY)and 8.0-9.0 ka are also responses in the sediment.[Conclusions]This study provides basic data and information for the Holocene climate reconstruction of Liaodong Peninsula,particularly for the sedimentary environment evolution history of the west coast of Dalian.