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位于巴丹吉林沙漠东南缘的查格勒布鲁剖面CGS1层段记录了全新世以来显示风力强弱的沙丘砂与黄土堆积旋回。以Md(Φ)、Mz(Φ)的5Φ(31.5μm)为界,可以划分出10个“C1—C10”明显的和1个“C11”较弱的(<5Φ)旋回变化。其中,有7个属于沙丘砂与之上覆黄土或古土壤构成的旋回。这些旋回在Md(Φ)、Mz(Φ)上显示出多谷峰波动的形式。不仅如此,粒度的σ、SC/D值和>63μm含量亦随之响应。研究认为,CGS1层段粗粒和细粒层位Md(Φ)等参数和>63μm含量的变化分别代表了东亚冬夏季风的作用过程;冬季风时期的C1与北大西洋IRD事件的冷期B0和B1,C2、C3、C4依次与B2、B3、B4,C7、C9、C10依次与B5、B6、B7在时间-气候性质上具有很好的对应;北大西洋B8冷期在CGS1中没有明显表现,但仍然能够在Md(Φ)、Mz(Φ)曲线上看到这是一个<5Φ的低值时期,而>63μm的含量相应增高;C5、C6和C8寒冷时段虽未见于北大西洋,但在中国一些地点却有发现。这些由若干粒度指标反映出来的寒冷事件表明,在全新世东亚夏季风活动盛行的总的形势下还存在频繁的千年尺度的冬季风波动。而尤为重要的是这些寒冷事件存在的与北大西洋寒冷事件的遥相关的关系表明,除C5、C6和C8以外的CGS1粒度记录的寒冷事件都隐含了北大西洋的强烈信号。从这个意义上来说,笔者讨论的内容可为全新世北半球的D/O震荡及其形成机制提供一个比较理想的东亚季风变化与中国沙漠区域环境响应的地质证据。
The CGS1 section of the Chagrebro section, located on the southeastern margin of Badain Jaran Desert, records accumulation of cycles of dune sand and loess that show strong winds since the Holocene. Taking the 5Φ (31.5μm) of Md (Φ) and Mz (Φ) as the boundary, 10 “C1-C10” obvious and 1 “C11” weaker (<5Φ) . Among them, 7 belong to the cycle of dune sand and overlying loess or paleosol. These rotations show a pattern of trough peaks on Md (Φ), Mz (Φ). Not only that, the size of the σ, SC / D values and> 63μm content also responded. The results show that the parameters of Md (Φ) and the content of> 63μm in the coarse grained and fine grained layers of CGS1 represent the process of the East Asian winter monsoon. The winter monsoon C1 and the North Atlantic IRD events B0 and B2, B3, B4, C7, C9 and C10 followed by B5, B6 and B7 in good temporal-climatic quality. The North Atlantic B8 cold period did not show significant effect in CGS1 , But it can still be seen on the Md (Φ) and Mz (Φ) curves that this is a low period of <5Φ and the content of> 63μm is correspondingly increased. Although the cold periods of C5, C6 and C8 are not seen in the North Atlantic Ocean, Found in some locations in China. These cold events, as reflected by a number of grain-size indicators, indicate frequent fluctuations in the winter millennium at the millennium scale, even under the overall prevalence of Holocene East Asian summer monsoon activity. What is particularly important is the teleconnection of these cold events with the North Atlantic cold events, indicating that the cold events recorded by the CGS1 grain sizes other than C5, C6, and C8 imply a strong signal from the North Atlantic. In this sense, the author’s discussion can provide a more ideal geologic evidence of the change of East Asian monsoon and the environmental response of desert regions in China during the Holocene D / O oscillations and their formation mechanism in the northern hemisphere.