Cross-dating methods of coral annual bands for reconstructing oceanic climate change

通过连接多个重建的古气候记录，研究了珊瑚骨骼的交叉定年方法。对采自日本琉球群岛Sekisei泻湖的全新世珊瑚化石进行了放射性碳年龄测定、年带计数和氧同位素比值测定。这些结果表明，从一些珊瑚样品的重叠年表中可以获得超过400年的古气候记录。此外，为了使氧同位素分析更简便、快速，对GasBench/同位素比值质谱法的精密度、分析时间和最佳条件进行了研究。

A cross-dating method for coral skeletons was examined by connecting plural reconstructed paleoclimate records to make their chronology longer. Holocene fossil corals were collected from Sekisei lagoon, Ryukyu, Japan, and their radiocarbon ages were determined, annual bands were counted, and oxygen isotope ratios were measured. These results indicate that more than 400-year paleoclimate record will be obtained from overlapped chronologies of some coral samples. Besides, to make oxygen isotope analysis simpler and quicker, the precision, analysis time and optimum conditions for coral samples were examined for GasBench/isotope ratio mass spectrometry.