山东山旺中新世硅藻土的纹层类型及成因  

Types and Origin of Diatomaceous Laminaeof the Miocene Shanwang Formationin Linqu,Shandong Province

作　　者：覃文圣[1] 刘建波[1] 韩宝福[1] 王宪曾[1] 李福昌 

机构地区：[1]北京大学造山带与地壳演化教育部重点实验室,北京100871 [2]山东临朐山旺化石博物馆,山东临朐262600

出　　处：《沉积学报》2004年第2期267-275,共9页Acta Sedimentologica Sinica

基　　金：国家自然科学基金资助项目 (批准号 :4990 2 0 0 3);科技部社会公益性项目中国重要地质遗产保护研究"山东山旺中新世生物群化石产地保护研究"(批准号 :2 0 0 1DIA2 0 0 2 5 - 3)资助

摘　　要：山东临朐山旺地区中新世山旺组硅藻土极为发育。通过对该地区硅藻土纹层的研究 ,确定其分类和成因 ,为进一步确立年纹层的存在、利用其进行高分辨率测年、探讨高频古气候旋回奠定基础。山旺组硅藻土的单层纹层厚度一般为 10 0 μm左右。依据纹层的物质成分 ,单层纹层可分为硅藻纹层、有机纹层和粘土纹层三种类型。各类单层纹层组合成为明暗相间的层偶 ,层偶厚度一般为 10 0～ 4 0 0 μm ,常常表现为浅色的硅藻纹层逐渐向深色的粘土纹层或有机质纹层渐变过渡。纹层层偶可分为 :薄层硅藻纹层—有机质层偶 ,厚层藻纹层—有机质层偶 ,薄层粘土纹层—有机质层偶 ,厚层粘土纹层—有机质层偶和硅藻纹层—粘土纹层层偶。山旺组硅藻土中不同类型的单层纹层以及层偶的形成主要受控于当时湖盆内粘土物质的沉积速率、硅藻的繁盛程度和有机物质的沉积和保存条件。The Miocene Shanwang Formation in Linqu of Shandong Province consists mainly of lacustrine diatomaceous sediments. Detailed sedimentary study on the laminated diatomites in the Shanwang Formation is necessary for the furtherwork on reconstruction of high-frequency climatic cycle. Based on the major mineral composition and their ratios, the diatomaceous sediments in the Shanwang Formation are distinguished as three distinct laminae (clay laminae, diatomaceous laminae and organic matter laminae) and three lamina couplet types (organic matter-clay couplet, organic matter-diatomaceous couplet and diatomaceous couplet- clay couplet). The formation of diatomaceous laminae and lamina couples in the Shanwang Formation was controlled by sedimentary rate of terrigenous clays, diatom growth, and deposition and preservation of organic matters in the basin.

关 键 词：硅藻土 纹层 层偶 中新世 

分 类 号：P619.265[天文地球—矿床学] P534.5[天文地球—地质学]