Stratigraphic development during the Late Pleistocene and Holocene offshore of the Yellow River delta, Bohai Sea Jian Liu a,b, * , Yoshiki Saito c , Hong Wang a,b , Liangyong Zhou a,b , Zigeng Yang b a Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology, Ministry of Land and Resources, PR China b Qingdao Institute of Marine Geology, Qingdao 266071, PR China c Geological Survey of Japan, AIST, Central 7, Higashi 1-1-1, Tsukuba, Ibaraki 305-8567, Japan article info Article history: Received 28 August 2008 Received in revised form 1 April 2009 Accepted 18 June 2009 Keywords: Late Pleistocene Holocene MIS 3 Sea-level change Yellow River delta Bohai Strait Bohai Sea abstract A 61-m-long sediment core (HB-1) and 690 km of high-resolution seismic profiles from offshore of the Yel- low River delta, Bohai Sea, were analyzed to document the stratigraphy and sea-level changes during the Late Pleistocene and Holocene. Accelerator mass spectrometry 14 C dating and analyses of benthic foram- inifera, ostracods, the mineral composition, and sedimentary characteristics were performed for core HB- 1, and seven depositional units (DU 1–DU 7 in descending order) were identified. The seismic reflection data were interpreted in light of the sedimentological data of the core and correlated with other well-stud- ied cores obtained previously in the Bohai Sea area. Seven seismic units (SU 1 to SU 7 in descending order) were distinguished and interpreted as follows: SU 7 corresponds to marine facies in Marine Isotopic Stage (MIS) 5; SU 6, to terrestrial facies in MIS 4; SU 5 and SU 4, to alternating terrestrial and marine facies (DU 7–DU 5) in MIS 3; SU 3, to terrestrial facies (DU 4) in MIS 2; SU 2, to Holocene marine facies (DU 3 and DU 2); and SU 1, to modern Yellow River delta sediments deposited since 1855 (DU 1). The sedimentary facies from DU 7 to DU 5 reflect sea-level fluctuations during MIS 3, and the boundary between DU 5 and DU 6, which coincides with that between SU 4 and SU 5, is a distinctive, laterally con- tinuous, undulating erosion surface, with up to 20 m of relief. This surface reflects subaerial exposure between transgressions during MIS 3. Estimated sea levels during MIS 3 ranged from 35 ± 5 to 60 ± 5 m or lower, with short-term fluctuations of 20 m. Sedimentary environments in the Bohai Sea area were governed mainly by eustatic sea-level changes and the Bohai Strait topography, which controls the entry of sea water into the Bohai Sea area. The mineral composition of the sediment core suggests that the Yellow River did not discharge into the Bohai Sea, or at least did not influence the study area significantly, during parts of MIS 3 and MIS 2 to the early Holocene (11–8.5 cal kyr BP). Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction During the past few decades, late Quaternary sea-level curves have been reconstructed, mostly on the basis of deep-sea oxygen isotope series (d 18 O) and coral reef records (e.g., Shackleton, 1987; Bard et al., 1996; Chappell et al., 1996; Yokoyama et al., 2001; Chappell, 2002). However, the reconstructed sea-level varia- tions suffer from inherent uncertainty and show discrepancies of up to tens of meters during certain time intervals (e.g., Marine Iso- tope Stage 3). Siliciclastic-dominated continental shelves provide an alternative source of sea-level data, and late Quaternary coastal and shelf deposits have recently proved to contain good strati- graphic records of sea-level and paleoenvironmental changes (e.g., Banerjee, 2000; Hanebuth et al., 2000; Yokoyama et al., 2000; Lobo et al., 2001; Marsset and Bellec, 2002; Hanebuth et al., 2003; Schimanski and Stattegger, 2005; Hanebuth et al., 2006; Liu et al., 2007). Water depth in the Bohai Sea is mostly less than 30 m, and the average depth is only 18 m (Fig. 1). The Bohai Sea is separated from the North Yellow Sea by the Bohai Strait and has been strongly af- fected by Quaternary sea-level changes. Qin et al. (1990) first sys- tematically studied Quaternary environmental evolution and stratigraphy in the Bohai Sea. More recently, Marsset et al. (1996) carried out detailed investigations of late Quaternary sedi- mentary sequences in the eastern Bohai Sea by high-resolution seismic analyses, and Yan et al. (2006) did the same in the western coastal plain of the Bohai Sea by drillcore analyses. However, high- resolution analyses of the late Quaternary stratigraphy in the Bohai Sea are relatively sparse, especially in the area around the Yellow River delta, where many studies have focused on the Holocene sed- imentation and stratigraphy and the modern sedimentary dynam- ics (e.g., Prior et al., 1986; Wright et al., 1988; Li et al., 1998; Saito et al., 2000). Owing to the high sedimentation rate, the late 1367-9120/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.jseaes.2009.06.007 * Corresponding author. Tel.: +86 532 85755832; fax: +86 532 857220553. E-mail address: liujian0550@vip.sina.com (J. Liu). Journal of Asian Earth Sciences 36 (2009) 318–331 Contents lists available at ScienceDirect Journal of Asian Earth Sciences journal homepage: www.elsevier.com/locate/jseaes