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福建海坛岛青峰老红砂剖面以棕红色砂层和黄橙色砂层的交替旋回变化为显著特征。通过野外考察、采样和测定分析,对青峰老红砂剖面的粒度特征及其古气候意义进行深入研究。结果表明:(1)青峰剖面棕红色砂层以细砂为主,黄橙色砂层以中砂为主,细砂-中砂在剖面上呈现明显的交替旋回变化;(2)棕红色砂层和黄橙色砂层的粒度频率曲线均以单峰加一细尾为主,含有一定量的粉砂、黏土;概率累积曲线以滚-跳-悬三段式为主,但两种砂层在组分含量、斜率等方面存在差异;(3)粒度参数呈现明显的波动旋回变化,可能指示沉积时期区域风力、搬运动力、化学风化强度方面发生了周期性变化,即棕红色砂层显示了暖湿气候条件下的红壤化过程,黄橙色砂层则显示凉干气候条件下的黄壤化过程。因此,青峰老红砂旋回沉积表明第四纪晚期以来,福建东部沿海的古气候古土壤可能经历了南亚热带(赤红壤)和暖温带(黄壤)的交替变迁。
The red mudstone section of Qingfeng, Haitan, Fujian Province, is characterized by alternating cycles of brownish red sandstone and yellowish orange sandstone. Through field investigation, sampling and determination analysis, the granulometric characteristics and its paleoclimate significance of the old Hongsha section of Qingfeng were studied in depth. The results show that: (1) the reddish-brown sand layer in Qingfeng section is dominated by fine sand, while the yellow-orange sand layer is dominated by medium-sand, while the fine-grained sand with medium alternating sag changes in the section; (2) And yellow-orange sand layer are mainly single peak and small tail with a certain amount of silt and clay. The probability cumulative curve is dominated by roll-jump-suspension three-stage model, (3) The particle size parameters show obvious fluctuation swirling, which may indicate that there is a periodic change in regional wind power, transport force and chemical weathering intensity during the sedimentary period, that is, the reddish-brown sand layer shows a warm In the wet climate, the process of red soil formation and the yellow-orange sand layer show the yellowing process under the condition of cool dry climate. Therefore, the Cyclotron deposition of Qingfeng Old Red Sand indicates that the paleoclimatic paleo-soils along the east coast of Fujian Province may have undergone the alternation of the South Subtropical Zone (red soil) and the warm temperate zone (yellow soil) since the late Quaternary.