对黄河三角洲ZKl孔粒度、岩性、微体古生物组合和”C年代进行了分析,探讨了研究区晚第四纪以来的沉积层序演化历史及其古环境意义。黄河三角洲的ZKl孔共发育三个海侵层,自下而上为深海氧同位素3期(MIS3)的第Ⅲ海侵层和第Ⅱ海侵层以及氧同位素1期(MISl)的第1海侵层,指示自氧同位素4期(MIS4)以来研究区共发生三次主要海平面波动。这三次海平面波动分别对应于渤海海侵、献县海侵和黄骅海侵。根据沉积记录信息,ZKl孔可分辨第1海侵层的河口三角洲相(5.63~14.04m)和滨岸浅海相(14.04~20.62m),第Ⅱ海侵层的滨岸浅海相(39.52~49.57m)和河口三角洲相(49.57~51.52m),第Ⅲ海侵层的滨岸浅海相(76.00)0~83.63m)和潮滩相(83.63~92.70m),均以特征的微体古生物组合和沉积相为标志。结合前人研究,阐明了本区自晚第四纪以来的海平面变化及沉积环境演变历史。
A 100-m-long sediment core (ZK1) from the modern Huanghe Delta (Bohai Sea) were analyzed to docu- ment the stratigraphy and sea-level changes since the Late Quaternary. Accelerator mass spectrometry ~4C dating and analyses of benthic foraminifera, ostracods, and sedimentary characteristics were analyzed for Core ZK1. Seven depo sitional units ( DU1 to DU7 in descending order) were identified and interpreted as follows : DU 7 corresponds to ter- restrial facies in MIS 4 ; DU 6 and DU 4, to alternating terrestrial and marine facies in MIS 3 ; DU 3, to terrestrial fa cies in MIS 2 ; DU 2, to Holocene marine facies ; and DU 1, to the modern Huanghe Delta sediments deposited since 1855. By correlation with other welt-studied cores in the nearby area, three transgressive layers of Core ZKI were in agreement with Bohai and Xianxian transgressions in MIS3, and Huanghua transgressions in MIS1. These sedimentary facies of Core ZK1 reflect several sea-level fluctuations since MIS4, which played a key role in controlling the sedi mentary environments in the study area.