High resolution C-14 AMS ages ( similar to 50 ka) of organic matter associated with the loess-palaeosol Holocene-Late Pleistocene (8-130 ka) sediments of Dilpur Formation, Karewa Group, Kashmir, India

摘要

High resolution C-14 AMS ages from sequential layers in the late Quaternary Dilpur Formation in Indian Kashmir, reveal glacial and inter-glacial climatic changes archived in this more or less complete aeolian-palaeosol record. The C-14 AMS ages are consistent and fit well within the time window of similar to 45-50 ka. Considering the thicknesses (at corresponding stratigraphic heights), the ages obtained for the Si palaeosol layer provided high resolution ages for the early Holocene period. When compared to the sedimentation rate based time estimates for the successive layers showed direct relationship between absolute ages and the time involved in the deposition. Based on the extrapolation of C-14 AMS ages of the Shankerpora section, the incidences of glaciations occurred at 67-71 ka and 124-127 ka. The glacial and interglacial cycles spanning similar to 130 ka encompass a variable number of palaeosols. Temporally, these observations correlate well with the two glaciations earlier reported from the loess palaeosol succession of Xiagaoyuan, Gansu Province, western Chinese Loess Plateau, suggesting perhaps that similar climatic conditions prevailed in this region.