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对湖北省郧西县庹家湾(TJW)剖面的地层序列、年代、磁化率及粒度组成进行研究。结果表明:TJW剖面具有表土(MS)→全新世黄土(L0)→古土壤(S0)→过渡层(Lt)→马兰黄土(L1)→黄土与砂互层(T1-al2)→砾石层(T1-al1)的地层序列;在马兰黄土层上部的黏粒含量、黏粒/粉砂值以及磁化率值明显高于典型马兰黄土,而接近古土壤(S0),其成壤作用明显,属于较典型的弱古土壤层(L1-S1和L1-S2),其年龄在27.3~21.6 ka B.P.之间。此现象反映了在汉江上游地区,晚更新世时期的冰期气候并不是持续稳定的,在27.3~21.6 ka B.P.期间存在相对短暂的温暖湿润阶段,这次气候事件可与黄土高原地区进行良好对比。
The sequence, age, magnetic susceptibility and grain size of the TJW profile of Yunxi County in Hubei Province were studied. The results show that the TJW profile is characterized by topsoil → L0 → ancient soil → Lt → Malan loess → T1-al2 → gravel layer T1-al1). The contents of clay, clay / silt and magnetic susceptibility in the upper part of Malan loess were significantly higher than those of typical Malan loess, but close to the ancient soil (S0) Compared with the typical weak paleosol layers (L1-S1 and L1-S2), their age ranged from 27.3 to 21.6 ka BP. This phenomenon reflects that in the upper reaches of the Hanjiang River, the glacial climate of Late Pleistocene was not stable and stable. During the period of 27.3-21.6 ka B.P., there was a relatively short period of warm and humid climate. This climate event can be compared with the Loess Plateau.