川东北宋家洞石笋氧碳同位素周期分析

Periodicity Analyses of Oxygen and Carbon Isotopes of a Stalagmite Retrieved from Songjia Cave,NE Sichuan in Central China

对采自川东北宋家洞的石笋SJ3的氧碳同位素值进行了小波分析和REDFIT分析,得到以下结果:(1)氧同位素值在18.3～17.5 ka有显著的174 a的周期,碳同位素值在16.2～15.4ka、18.3～17.8ka有显著的174 a的周期;(2)氧碳同位素值的周期与太阳活动周期有关。这些表明石笋记录在短时间尺度上与太阳活动存在显著关联。

Cycle components of oxygen and carbon isotopes of stalagmite SJ3, which was collected from Songjia Cave in NE Siehuan in Central China, were investigated with wavelet analysis and REDFIT. The results indicate that ： （ 1 ） there is a 174 a periodicity in oxygen isotope values during 18.3 - 17.5 ka, and a 174 a periodicity in carbon isotope values during 18.3 - 17.8 ka and 16.2 - 15.4 ka ; （ 2 ） the periodicities of oxygen and carbon isotope values are consistent with the periodicity of 179 a of solar activity. These results suggest that the O - C isotopes of SJ3 correlate closely with solar activity on short time scales.