Local marine reservoir age variability at Luzon Strait in the South China Sea during the Holocene

Abstract

Here, we report new estimates of local marine radiocarbon reservoir ages from northwestern Luzon Island in the Philippines, on the east side of the South China Sea. Data for two periods, through the 1940’s and the mid-Holocene, were derived from modern and fossil corals. Our results from Luzon Island show variable ΔR values, from −39 ± 25 to 337 ± 27 14C yr over the past 6000 years and highlight the importance of understanding temporal ΔR changes to obtain accurate radiocarbon dates for mid-Holocene samples. An abrupt shift in ΔR at ∼5.5 ka BP, in the east side of the South China Sea, can be attributed to changes in the intensity of the upwelling, in the eastern Pacific, and to the East Asian Monsoon. Additional reservoir age data from the Pacific is likely to reveal details of oceanographic and climate changes at this time.