Quaternary Stratigraphic Division and Paleoenvironmental Evolution Observed from Core LZK1 on Hengsha Island, Shanghai

• Published in: Acta geologica Sinica (Beijing) Vol. 94; no. 4; pp. 1167 - 1177
• Main Authors: KE, Xue, XIE, Jianlei, ZHANG, Zongyan, ZOU, Yarui, WANG, Guoquan
• Format: Journal Article
• Language: English
• Published: Richmond Wiley Subscription Services, Inc 01.08.2020; Institute of Geological Survey,China University of Geosciences,Wuhan 430074,China; State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430074,China%Shanghai Institute of Geological Survey,Shanghai 200072,China%Wuhan Center,China Geological Survey,Wuhan 430205,China%Hubei Institute of Geosciences,Wuhan 430034,China%Department of Earth and Atmospheric Sciences,University of Houston,Houston,TX 77204,USA
• Edition: English ed.
• Subjects: chronostratigraphic framework; Cores; Coring; Dating techniques; Environments; Floodplains; Freshwater; Gravity; Holocene; Inland water environment; Lakes; Lithology; marine transgression; paleoenvironmental evolution; Pleistocene; Quaternary; Sediment; Sediments; Sequencing; Stratification; Stratigraphy; Yangtze delta; paleoenvironmental evolution; marine transgression; chronostratigraphic framework; Quaternary; Yangtze delta
• ISSN: 1000-9515; 1755-6724
• DOI: 10.1111/1755-6724.14564

The Quaternary sediments in the Yangtze delta are loose and lack precise stratification marks in the lithology. Moreover, due to the limitations of dating methods, it is difficult for Quaternary cores to deliver accurate age constraints. Thus, it is a challenge to establish the Quaternary stratigraphic framework. Gravity core LZK1 was drilled on Hengsha Island, Shanghai, in the Yangtze delta, in 2012. The core was terminated at 403.83 m below the local land surface, the uppermost 291.2 m comprising a thick sequence of Quaternary sediments. This study investigated the stratigraphic subdivision and paleoenvironmental change of the Quaternary sediments. From bottom to top, the Quaternary stratigraphic sequence can be subdivided into the lower Pleistocene Anting Formation, Middle Pleistocene Jiading Formation, Upper Pleistocene Chuansha Formation and Nanhui Formation, Holocene Loutang Formation, Shanghai Formation, and Rudong Formation. According to this study, the Hengsha Island area was dominated by a freshwater lacustrine environment during the early Pleistocene, an alternation of shallow lake and shore lake environment during the Middle Pleistocene, a delta plain to lagoonal environment during the early Upper Pleistocene, a fluvial channel to floodplain environment from the LGM (Last Glacial Maximum) to the end of the Upper Pleistocene, and a delta environment during the Holocene.