HIGH-RESOLUTION CARBON AND OXYGEN ISOTOPE RECORDS FROM STALAGMITE AND PALAEOCLIMATE IN HESHANGDONG CAVE, QINGJIANG, HUBEI PROVINCE
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摘要: 通过对湖北清江和尚洞HS - 2号石笋的沉积特征及碳、氧同位素特征分析, 利用U系法定年, 获取了湖北地区19.0~6.9ka的古气候、古环境信息(平均分辨率为17a, 局部分辨率达到7a).得出如下结论: (1) 19.0~16.6ka, C, O同位素偏轻, 气候冷湿; (2) 16.6~11.1ka, C, O同位素偏重, 气候干热; (3) 11.1~10.3ka干热时期中的突然回冷事件对应于新仙女木事件; (4) 10.3~6.9ka气候温和, 雨量较丰, 后期逐渐变冷.反映了历史时期湿冷、干热、温暖交替变化的气候趋势, 得出了千年级和百年级的一些气候变化趋势Abstract: The palaeoclimatic and palaeo environmental information in Hubei region 19.0 to 6.9 thousand years ago is obtained from the analyses of the sedimentary, carbon and oxygen isotope features of the stalagmite numbered as HS-2 in the Heshangdong cave, Qingjiang, Hubei and with the uranium series dating method. The following four climate changes can be concluded (with the average resolution 17 a, and the local resolution 7 a) : (1) In 19.1~16.6 ka, the smaller values of both δ(13C) and δ(18O) suggest a cooler and wetter climate. (2) In 16.6~11.1 ka, the greater values of both δ(13C) and δ(18O) suggest a dry and warm climate. (3) In 11.1~10.3 ka, the sudden return of the cold climate in the dry and hot period may have corresponded to the Younger Dryas event. (4) In 10.3~6.9 ka, the change from the warm and rainy climate to the cold climate reflects the alternate changes from humid, cold, dry hot, up to the warm weather, showing some climate change patterns in the order of 100 or 1 000 years.
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Key words:
- carbon and oxygen isotopes /
- stalagmite /
- palaeoclimate /
- palaeovegetation /
- Heshangdong cave /
- Hubei Province
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表 1 和尚洞SH-2-1石笋沉积特征
Table 1. Sedimentary characteristics of stalagmite in Heshangdong cave
表 2 和尚洞石笋同位素反应的平衡数据
Table 2. Evidence of isotopic equilibrium reaction in stalagmite in Heshangdong cave
表 3 石笋铀系年龄数据
Table 3. 230Th-U ages data of stalagmite
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