Sr and Nd isotopic compositions of a sediment core from the Bay of Bengal are used to constrain the provenance and transport pathways of their terrigenous component during the ∼3 to 34 14C kyr BP. The results clearly demonstrate a distinctly different source for detrital fluxes on the Ninetyeast Ridge from that of distal and western Fan sediments. There is a systematic pattern of climate‐related variability in 87Sr/86Sr and ɛNd(o) values at the studied location. Pulses of low 87Sr/86Sr, higher radiogenic Nd and high silt content occurring at ∼5–7 kyr intervals suggest significant changes in the detrital source. Increased supply of Irrawaddy‐derived sediments appears to be the dominant source for these pulses. Our results support the hypothesis that rapid cold events of North Atlantic (Heinrich events) are characterized by the intensified northeast monsoon.

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Previous studies showed that the Rajmahal‐Sylhet‐Bengal (RSB) flood basalt province (117 ± 2 Ma) in eastern India was spatially close to the active Kerguelen hotspot about 118 Ma ago. Yet, it could not be unequivocally correlated to this hotspot due to wide variation in isotopic compositions of both the RSB and Kerguelen plateau basalts. However, we report Sr‐Nd‐Pb isotopic compositions (87Sr/86Sri: 0.70535 to 0.70561; εNd(T): −2.6 to −3.2; 206Pb/204Pbi: 17.88 to 18.07) of a co‐eval (116 ± 2 Ma) Group II kimberlite from this flood basalt province that is identical to recently identified pristine Kerguelen plume basalts from the Kerguelen Plateau/Archipelago and Broken Ridge. This suggests that the Kerguelen hotspot could indeed be responsible for the ∼117 Ma magmatic activity in Eastern India.

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