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对采集衡阳盆地松木剖面的红粘土进行了ESR定年和元素、碳氧稳定同位素测试分析,结果表明:松木剖面δ~(13)C曲线和δ~(18)O曲线的相位和形状基本相同。碳氧同位素曲线图显示,1.78Ma B.P.~1.56Ma B.P.期间,碳氧同位素偏轻,为温暖湿润气候;1.56Ma B.P.~0.716Ma B.P.时期,碳氧同位素稍偏重,指示为冷干气候;0.716Ma B.P.以后,碳氧同位素偏重,干冷程度比上阶段增强。松木红土剖面δ13C曲线和段家坡黄土剖面δ13C曲线在频率和变化趋势方面相近似,记录了构造尺度上三次气候环境变化,早更新世晚期以来衡阳盆地古气候朝着干冷方向发展,与全球气候波动模式基本一致。
ESR dating, elemental and carbon-oxygen stable isotope analysis of red clay collected from the pine woody section of the Hengyang basin show that the phase and shape of the δ ~ (13) C curve and the δ ~ (18) O curve of pine wood are basically the same. Carbon and oxygen isotope curves show that the carbon and oxygen isotopes are light and warm and humid during the period of 1.78Ma BP to 1.56Ma BP. Carbon and oxygen isotopes are slightly heavier and heavier than 1.56Ma BP ~ 0.716Ma BP, indicating a cold and dry climate; 0.716Ma After BP, the carbon and oxygen isotopes are heavier and the degree of dry and cold is stronger than the previous stage. The curves of δ13C of pine clay and δ13C of Duanjiapo loess section are similar in frequency and variation tendency, and recorded the three climate changes on the tectonic scale. Since the late Early Pleistocene, the paleoclimatic evolution of the Hengyang basin has progressed towards dry and cold, Fluctuation patterns are basically the same.