南黄海QC＿2孔的ESR年代学

ESR CHRONOLOGY OF WELL QC_2 IN TBE SOUTH YELLOW SEA

本文报道了南黄海ＱＣ＿２孔３３个ＥＳＲ测年结果，它们和￣（１４）Ｃ年龄，微体古生物地层学及磁性地层学的结果相一致，符合地质情况，建立了一个较完整的年代学序列。用海洋沉积物中石英Ｇｅ心信号可得到沉积物几十万年内的沉积年龄，石英Ｅ＇心的天然光效应使沉积物的ＥＳＲ测年陷入了困境，但通过调整测试条件（增大微波功率），在海洋沉积环境中，仍可以利用石英的Ｅ＇心得到较老沉积物（大于５０万年）的较为可靠的ＥＳＲ年龄。

Well QC_2(34°18'N, 122°16'E)is located on the offshore slope in the northeast of thePleistocene Yangtze Rive delta and to the east of the ancient Yellow River delta. The av-erage recovery from QC_2 is up to 90.4%,and the core nearly reaches the top boundary ofOlduvai subchron. For Quaternary studies,QC_2 is one of the best wells in China with ob-vious geologic settings.The ages of 33 samples which were taken from QC_2 in the South Yellow Sea weredetermined by ESR method.The correlation of ESR ages with ￣(14)C ages,microbios-tratigraphy and magnetostratigraphy,shows a correspondence with the horizons and alsowith the geological backgrounds.The ESR ages build a more complete chronology,andthe maximum ESR age is 1.9Ma.Reliable ESR ages of sediments within several hundredthousand years can be obtained from Ge centres of quartz in sediments,while the ESRages of older sediments(more than 5 ×10￣5 a)can be obtained from E'centres of quartzin marine conditions by using a higher microwave power.