Optically stimulated luminescence dating of Holocene palaeoflood deposits in the middle reach of the Yongding River, China
Optically stimulated luminescence dating of Holocene palaeoflood deposits in the middle reach of the Yongding River, China
复制标题
永定河中游全新世古洪水沉积物光激发光测年
DOI：
10.1016/j.quaint.2017.02.013
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发表时间：
2017
影响因子：
2.2
通讯作者：
Wang JP
中科院分区：
文献类型：
--
作者：
Zhao Xiaohong;Wang Junping;Wei Mingjian;Pan Baolin;Li Xiaopeng;Wang Junping;Fan Majie;Lai Zhongping;Zhao Junxiang;Zhao Yanhong;Zhao Qiuyue;Wang JP
古森林沉积物记录了极端的气候和环境事件。而历史资料显示，永定河洪水在我国频繁发生，造成了许多自然灾害。永定河古森林的沉积学记录一直没有得到很好的研究。本文对永定河中游炭木沟遗址的古森林进行了研究。在沉积物剖面中发现了6个古森林事件。应用光释光法建立了古南极洲沉积物的年代学。采用改进的单次再生剂量（SAR）法和标准生长曲线（SGC）法测定等效剂量（De）。应用最小年龄模型（MAM）、中心年龄模型（CAM）和算术平均数计算贬值。光释光测年结果表明，这些古气候事件发生在全新世，集中在8.5- 7.3ka、2.8- 2.4ka和1- 0.5ka三个阶段。永定河的这些古气候事件的时间与中国其他水系的古气候事件的时间相吻合。与中国连续高分辨率气候记录相比，这些古气候事件发生在气候转型期。
Palaeoflood deposits record extreme climatic and environmental events. While historic data show that floods occurred frequently in the Yongding River in China and have caused many natural disasters. The sedimentologic records of palaeoflood in the Yongding River have not been well studied. This study investigates the palaeoflood deposits at the Tanmugou site in the middle reach of the Yongding River. Six episodes of palaeoflood were identified in the sediment profile. Optically stimulated luminescence (OSL) dating method was applied to establish the chronology of the palaeoflood deposits. Both the improved single-aliquot regenerative-dose (SAR) protocol and standard growth curve (SGC) method were employed for equivalent dose (De) determinations. The minimum age model (MAM), central age model (CAM) and arithmetic mean were applied to calculate the Devalues. The OSL dating results show that these palaeoflood events occurred in the Holocene and concentrated during three stages, including 8.5–7.3 ka, 2.8–2.4 ka and 1–0.5 ka. The timings of these palaeoflood events in the Yongding River coincide with the timings of palaeoflood events in other river systems in China. Compared with the continuously high-resolution climate record in China, these palaeoflood events occurred during climate transition periods.