OSL and ¹⁴C ages of the Late Quaternary sediments in the east Pearl River Delta

Abstract: The dating of the Late Quaternary sediments in the east Pearl River Delta has great significance in many aspects, such as the study of the delta's evolution, the fluctuation of the ancient sea level and fault activities. The OSL and 14C dating was performed for the core from seven drill holes in Dongjiang plain, and sporopollen and micropaleontology analysis was conducted. Different from the former conclusion based mainly on 14C age that the oldest deposit of the delta is less than 40 000 a, the authors' OSL dating demonstrates that the age of the lower strata is about 47 000 to 135 000 a. Based on a preliminary analysis of the age reliability and stratigraphic geochronological framework of the two transgression cycles during the Late Quaternary, the authors hold that the first transgression of the east Pearl River Delta might have occurred 40 000 to 80 000 a ago, and the erosion and weathering effect led to the considerable stratigraphic gap between the two transgressions.