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全新世早期是太阳辐射加强、全球温度上升,并伴随着冰盖消融的重要时期,而其间发生的冷事件以及亚洲季风区的弱夏季风事件的成因一直是全新世早期研究的重点。对亚洲季风—海洋—极地联系研究有着重要的意义。通过分析湖南莲花洞LHD5石笋28个U/Th年龄和535个氧同位素数据重建了全新世亚洲季风演化特征,其中全新世早期分辨率达8年。LHD5石笋记录到YD结束时间为11 748±30 a B.P.,全新世开始于11 684±39 a B.P.,转换时间约为64年,与格陵兰gicc05记录在误差范围内一致。LHD5石笋记录到全新世早期6次弱夏季风事件,事件年龄中心点分别为11 461±34 a B.P.、10 354±36 a B.P.、9 957±25 a B.P.、9 062±36 a B.P.、8 744±23 a B.P.、8 144±24 a B.P.,其δ18O值的波动幅度分别为1.08‰、0.94‰、0.66‰、0.90‰、0.55‰、1.02‰,这些弱季风事件在亚洲季风区具有普遍的区域意义。除8.2 ka事件之外,10 ka B.P.之前的弱季风事件除了受到太阳活动的影响,还受到北大西洋IRD事件的影响,而之后更多地受到太阳活动和ITCZ南移的影响。
The early Holocene is an important period of solar radiation intensification, global temperature rise accompanied by ice sheet ablation. The occurrence of cold events during this period and the causes of weak summer monsoon events in the Asian monsoon area have been the focus of early Holocene research. It is of great significance to study the Asian monsoon-ocean-polar contact. Through the analysis of 28 U / Th ages and 535 oxygen isotope data of LHD5 stalagmite in Lianhua Cave, Hunan, the evolutionary characteristics of the Holocene Asian monsoon were reconstructed. The resolution of the Holocene early was 8 years. LHD5 stalagmite recorded a YD ending time of 11 748 ± 30 a B.P. Holocene began at 11 684 ± 39 a B.P., with a conversion time of about 64 years, consistent with the Greenland gicc05 record within the error range. LHD5 stalagmite recorded 6 weak-summer monsoon events in the early Holocene, with age events of 11 461 ± 34 a BP, 10 354 ± 36 a BP, 9 957 ± 25 a BP, 9 062 ± 36 a BP, 8 744 ± 23 a BP and 8 144 ± 24 a BP, the δ18O values fluctuated by 1.08 ‰, 0.94 ‰, 0.66 ‰, 0.90 ‰, 0.55 ‰ and 1.02 ‰, respectively. These weak monsoon events were common in the Asian monsoon region significance. In addition to the events of 8.2 ka, the weak monsoon events before 10 ka B.P. were influenced not only by solar activity, but also by the North Atlantic IRD event, and then more by the solar activity and ITCZ southward migration.