Paleoclimatic reconstruction of the Karewa deposits of Kashmir Valley, northwest Himalaya: A review

Abstract

Plio-Pleistocene sedimentary successions, comprised of fluvio-glacial-lacustrine sediments capped by loess, are widespread in the Kashmir Valley, NW Himalaya, India. These sediments act as a repository of climate records for the past 4.4 Ma suggesting the dominance of southwestern monsoon up to 1.95 Ma and thereafter the dominance of mid-latitude western disturbances in the region. However, the younger strata of the loess-paleosol sequences (LPSs), <200 ka old, and Holocene sediments have been studied for high-resolution climate records compared to older archives because of the contentious chronological issues of the older deposits. Earlier studies revealed moderate climatic conditions from ∼65.8 ± 7.2 ka to 44.3 ± 5.8 ka, followed by periods of extreme dry phases of enhanced wind velocity, coinciding with the last major magnetic inversion. The climatic conditions have produced strong pedogenic signatures on the LPSs during the MIS-3 (∼43–34.7 ± 2.3). The dry arid climate phases recorded during the MIS-2 stage up to ∼14.7 ± 5.4 ka revealed a weak pedogenic alteration and a high amount of CaCO3 accumulation in the loess. Subsequent sporadic alluvial deposition of sediments over the LPSs implies widespread precipitation and glacial melting linked to the onset of the Holocene warming punctuated by dry and cold climate phases corresponding to the Bond events of 0, 3, 4, 5, and 7, which indicated a westerly-dominated climate during the Holocene. This review therefore critically examines existing literature on Karewa deposits in the Kashmir Valley, identifies knowledge gaps, and offers recommendations for future research, emphasizing their paleoclimatic potential for the Quaternary Period.