Enormous Ganges-Brahmaputra sediment discharge during strengthened early Holocene monsoon

摘要: Rivers are the main source of terrigenous sediment delivered to continental margins and thus exert a major control on coastal evolution sequence development. However, little is known about past changes in fluvial loads despite recognition significant variation under changing climatic regimes. In this study we present first quantified estimate discharge for river system conditions an intensified early Holocene monsoon. Development Ganges-Brahmaputra River delta began ca. 11000 yr B.P., when rising sea level flooded Bengal basin, thereby trapping most river's inner margin. Chronostratigraphic data from these deltaic deposits used calculate rates storage margin, which provide minimum load. Results reveal that ∼5 × 1012 m3 was stored basin 7000 corresponds mean load 2.3 109 t/yr. comparison, modern ∼1 t/yr, ranking it among world's rivers underscoring significance two-fold increase sustained over 4 k.y. Furthermore, timing immense strongly suggests its relation stronger than southwest monsoon South Asia. Similar patterns high monsoon-related have been noted throughout tropics subtropics, suggesting widespread fluviosedimentary response, potential magnitude showcased by system.