MICROPALEONTOLOGICAL RECORDS OF LATE QUATERNARY TRANSGRESSION IN THE MODERN PEARL RIVER DELTA REGION,GUANGDONG PROVINCE,S.CHINA

The history of sea level fluctuations is critical for understanding the evolution of geological environment in the low altitude coastal area.Based on the AMS and OSR datings and the sediment characteristics,the faunal microfossils are analyzed in sediments from the cores QZK1 and QZK4in the modern Pearl River Delta(PRD)region.The microfossils of foraminifera and ostracoda are only found in the Holocene gray-clay layers.The distribution patterns of the faunal microfossils indicate that the Holocene transgression began at the early Holocene or a bit earlier—the late Pleistocene,and the sediment at depth~620cm in the Core QZK4 possibly recorded the highest sea level during the Holocene in the modern PRD region,then the sea level fell to recent level;However,during the time for the previously reported late Pleistocene transgression,only terrestrial strata revealed in the two cores and there was no transgression layers been recognized.