Production rate variation and changes in sedimentation rate of marine core dated with meteoric 10Be and 14C

The first measurement of meteoric beryllium-10 (¹⁰Be) using Accelerator Mass Spectrometer (AMS) is reported from PRL-AURiS (Physical Research Laboratory-Accelerator Unit for Radioisotope Studies). Strategically, the meteoric ¹⁰Be dating method can date events as old as 10 Myr, and its accuracy while dating marine sediment cores has been well tested with magnetic methods. An attempt is made for a comparative study between radiocarbon (¹⁴C) and meteoric ¹⁰Be dating methods from a 6 m long sediment core collected from the equatorial Indian Ocean. The core was dated using both radiocarbon and meteoric ¹⁰Be and results showed remarkable similarity for both methods in terms of the sedimentation rate. A continuous age offset observed within 50 kyr could be due to a continuous influx of sediment with low ¹⁰Be content and that may have caused the meteoric ¹⁰Be ages to be younger. The sedimentation rate calculated by changing the ¹⁰Be depositional flux rate from 1.5 to 2.5 × 10⁻² atoms.cm⁻².s⁻¹ shows large variation, indicating the choice of appropriate ¹⁰Be depositional flux rate for the region. Additionally, being the first meteoric beryllium-10 measurements using AURiS, we have also discussed and reported the laboratory protocols and efficiency based on repeat standard and blank measurements.