TIMS U-series ages of speleothems from the Tangshan caves, Nanjing

U-series ages of a set of speleothem samples from the two caves near Tangshan Town, Nanjing, determined by thermal ionization mass spectrometry (TIMS), range from older than 500 KaBP to around 20 kaBP. These dated speleothems with unequivocal stratigraphic layers in cave sediments provide basic data to establish a geochronologic sequence for the cave sediments. Together with the buried layers of two hominid craniums, it is argued that the two fossil craniums, probably transported into the cave, deposited in different geological periods. The ages of one flowstone sample and stalagmites mark an upper limit of 500 KaBP for geochronology of No. 1 fossil cranium, and suggest No. 2 fossil cranium deposited within the age range of 500-240 KaBP.