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凤州黄土剖面代表了秦岭黄土特征 .该剖面由 33层黄土和 33层古土壤组成 ,厚约 82m ,下伏第三纪红粘土 .该剖面包括了布容正极性带和松山负极性带 ,二者的界线 (B/M )位于L8中部 .松山负极性时黄土记录了加拉米洛 (J)、奥尔都维 (O)和留尼旺 (R)亚时 .松山负极性带与高斯正极性带的界线 (M /Ga)位于黄土与第三纪红粘土分界处 .凤州黄土堆积大约始于 2 48Ma前 .凤州黄土剖面磁化率曲线反映出秦岭近 2 48Ma来的古气候变化至少发生过 33次干冷_湿热旋回 .它的波动特点与深海复合δ18O曲线记录的气候变化基本吻合 .
The section of Loess Plateau represents the loess characteristics of Qinling.The section consists of 33 layers of loess and 33 layers of paleosol, with a thickness of about 82m and underlying Lower Tertiary red clay.The profile includes the positive and negative belt of cloth capacity, The boundary between the two (B / M) is located in the middle of L8 Songshan negative polarity of the loess recorded Galamilles (J), Aldousu (O) and Reunion (R) The boundary line (M / Ga) of positive Gaussian band is located at the boundary of loess and Tertiary red clay, and the accumulation of loess in Fengzhou starts from about 48 Ma. The magnetic susceptibility curve of Loess section reflects the paleoclimate of Qinling in the past 24-48 years The change has occurred at least 33 times of dry-wet-hot cycles, and its fluctuation characteristics are basically consistent with those recorded by the deep sea composite δ18O curve.