福建海坛岛青峰老红砂旋回沉积的粒度特征及其古环境意义  

Grain-size Characteristics and the Paleoenvironmental Significance of the Cyclically Deposited "Old Red Sand" in Qingfeng,Haitan Island,Fujian,China

作　　者：申健玲 李志忠[1,2,3] 靳建辉[1,2,3] 邓涛[1,2] 姜锋[1,2] 苑秀全 于晓莉[1,2] 赖海成 

机构地区：[1]福建师范大学地理科学学院,福建福州350007 [2]福建师范大学湿润亚热带生态地理过程教育部重点实验室,福建福州350007 [3]福建师范大学地理研究所,福建福州350007

出　　处：《中国沙漠》2016年第4期972-982,共11页Journal of Desert Research

基　　金：国家自然科学基金项目(41271031;41301012);福建省自然科学基金项目(2013J01153);福建省科技厅公益类科研院所专项基金项目(2013R09);福建省教育厅A类科技项目(JA11061)

摘　　要：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 ＂Old Red Sand＂ of Qingfeng Profile in northwestern Haitan Island is characterized by its cycli- cal variaton of red-brown sand layers and yellow-orange sand layers. In this paper, we focused on further re- search of the grain size characteristics and the paleoenvironmental significance of Qingfeng Profile. The re- suits showed that： （1） The red-brown sand layers are mainly composed of fine sand, and the yellow-orange sand layers are medium sand. The Qingfeng Profile is featured with its alternating cycle of fine sand and me- dium sand. （2） The grain size frequency distribution curves of Qingfeng Profile present similar singlet with a thin tail, showing that the ＂Old Red Sand＂ contains a certain amount of silt and clay. Although the long- probability curves are both given priority to three stages, there are still some differences in component and slope. （3） The variation of grain size parameters with depth of Qingfeng Profile presents obvious fluctuation changes, showing that the wind conditions, transport dynamic and weathering intensity in sedimentary peri- od have experienced cyclical change. The red-brown sand layers show the process of latosolic red soil in the warm-wet climate, and the yellow-orange sand layers show the process of yellow soil in the cold-dry climate. The sedimentatry cycles of Qingfeng Profile may be recorded the alternating change of south subtropic （latosolic red soil） and warm temperate（yellow soil） in the east coast of Fujian Province since the late Qua- ternary.

关 键 词：老红砂 粒度特征 沉积旋回 气候变迁 土壤带迁移 海坛岛 

分 类 号：P531[天文地球—古生物学与地层学]