Quaternary fluvial and eolian deposits on the Belan river, India: paleoclimatic setting of Paleolithic to Neolithic archeological sites over the past 85,000 years

Abstract

Archeological sites in the bedrock Belan Valley at the southern margin of the Ganga Plains of India have unearthed Paleolithic to Neolithic artifacts and the first known evidence for rice cultivation. We present a sedimentological and paleoclimatic analysis for Belan sections, incorporating new luminescence and radiocarbon dates and a compilation of previous research. Some 20 m of strata are exposed in fluvial terraces, commencing with pedogenic and channel calcretes linked to groundwater ponding on the underlying bedrock. Overlying alluvium deposited from mixed-load meandering rivers yields dates between 85±11 and 72±8 kyr before present (BP), implying sustained fluvial activity during Marine Isotope Stage 5 and later; these strata contain Middle Paleolithic artifacts. Thin reworked gravels with Upper Paleolithic artifacts are dated at ∼21–31 kyr BP, and may represent declining alluviation and floodplain gully erosion during reduced monsoonal activity around the Last Glacial Maximum (LGM).