Coastal GIA processes revealed by the early to middle Holocene sealevel history of east China

TitleCoastal GIA processes revealed by the early to middle Holocene sealevel history of east China
Publication TypeJournal Article
Year of Publication2020
AuthorsXiong H, Zong Y, Li T, Long T, Huang G, Fu S
JournalQuaternary Science Reviews
Volume233
Date Published04/2020
Abstract

In order to examine relative sea-level responses to the postglacial ice-volume change and the glaciohydro isostatic adjustments (GIA), this study investigated the inner part of the Hangzhou Bay, east China, a tectonically relatively stable far-field location, and reconstructed the early to middle Holocene sea-level history. This investigation has established the elevational relationship between modern saltmarsh-mudflat and tidal levels based on diatom analysis for sea-level indicative meaning estimates, produced 17 high-quality sea-level index points, and simulated GIA processes for the study site. These results reveal that the relative sea level rose from similar to 38.3 +/- 1.6 m in c. 10,000 cal a BP to the present height by c. 7000 cal. a BP, and the average rate of sea-level rise decreased gradually from 19.6 +/- 2.6 mm/a to 2.3 +/- 1.5 mm/a during the 3000 years. This period of sea-level history was punctuated by two episodes of accelerated rise around 8200 and 7500 cal a BP. The relative sea level rose to 0.8 +/- 1.4 m above msl by c. 6500 cal. a BP, followed by a gradual fall back to the present height at 4500 cal a BP, implying a different response to the potential additional ice melting between 7000 and 4000 cal a BP. A comparison of the sea-level histories between the inner and outer Hangzhou Bay indicates the coastal levering effect due to the marine inundation of the continental shelves. A further comparison between sea-level data from China and Malay Peninsula reveals different GIA effects between the Cathaysia-Yangtze Blocks and the Sundaland Block.

DOI10.1016/j.quascirev.2020.106249