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采自陕西省柞水县的石笋给出了过去 750a来的高分辨率气候记录以及全新世和80～ 330ka之间的低分辨率的气候变化。定年方法使用了石笋生长纹层计数法、2 10 Pb法和TIMS2 30 Th法。分析了石笋中δ18O和δ13C的气候含义 ,认为当δ18O和δ13C值变重时 ,指示干热的气候组合 ,当δ18O和δ13C值同时变轻时 ,指示湿冷的气候组合。在长时间尺度δ18O值的变化以反映温度变化为主 ,δ13C值的变化反映湿度变化为主。当δ18O变轻 ,而δ13C变重时 ,指示干冷气候。这时期的夏季风很弱而冬季风很强 ,相反 ,当δ18O变重 ,而δ13C变轻时 ,指示湿热气候 ,表明夏季风很强 ,冬季风很弱。过去 750a的记录中分为 :公元 12 50～ 152 0年的温暖中世纪 (MedievalWarmPeriod) ,公元 152 0～ 182 0年的湿冷小冰期 (LittleIceAge)和公元 182 0年以来的温热期。全新世的气候在 4 0 0 0a左右有一显著的变化。在此时之前的温度低于全新世的平均气温 ,而在此之后的温度高于全新世的平均气温。全新世气候记录可细分为 18个不同的时期。
Stalagmites collected from Zhashui County, Shaanxi Province, provide high-resolution climate records over the past 750 years and low-resolution climate changes between the Holocene and 80-330 ka. The dating method uses stalagmite growth pattern counting method, 2 10 Pb method, and TIMS 2 30 Th method. The climatic implications of δ18O and δ13C in stalagmite were analyzed. It is considered that the combination of climate indicating dry-hot when the values of δ18O and δ13C become heavier, indicating that the δ18O and δ13C values are lighter at the same time, indicating a wet-cold climate combination. The change of δ18O value on a long time scale mainly reflects the temperature change, and the change of δ13C value reflects the change of humidity mainly. When δ18O becomes lighter, while δ13C becomes heavier, it indicates a dry and cold climate. In this period, the summer monsoon was weak and the winter monsoon was very strong. On the contrary, when δ18O became heavier and δ13C became lighter, it indicated a hot and humid climate, indicating a strong summer monsoon and a weak winter monsoon. The records of the past 750 years are divided into Medieval Warmer Period from 1250 to 1520 AD, Little Ice Age from 152 0 to 18 0 AD, and warm-up period from AD 182. The Holocene climate has a significant change around 400o. The temperature before this time was lower than the average temperature of the Holocene, and the temperature thereafter was higher than the average temperature of the Holocene. Holocene climatic records can be subdivided into 18 different periods.