Intertidal mangrove mudflat ^240+239Pu signatures, confirming a ²¹⁰Pb geochronology on the southeastern coast of Brazil

A sediment core was taken to determine if sediment accumulation rates could be conducted using Pu240+239 signatures in the coastal mangrove mudflats of southeastern Brazil. The results from this study show that Pu240+239 fallout activities are sufficient and well preserved in the coastal sediments of this region. Sediment accumulation rates determined from the Pu240+239 signatures were 4.4 mm/year and 4.1 from Pb-210 (CIC) method. A sediment mixing coefficient rate was calculated using chlorophyll-a profile (9.5 cm(2)).