摘要
通过对兰坪盆地古近纪野外剖面中含盐泥岩—泥质粉砂岩—粉砂岩微量和常量元素的测定,利用Adams和Couch古盐度计算公式、Walker“相当硼”判别法及锶钡比值法定量—半定量地分析了该区古盐度特征。结果表明,古盐度在6.5‰～22.05‰之间,盐度变化明显,以半咸水沉积为主,其次为淡水沉积。沉积中心主要位于云龙县—兰坪县一带,古盐度值最高,平面上表现为从沉积中心向盆地周缘盐度逐渐降低,并与其所伴生的沉积环境表现出良好的对应关系。结合盆地沉积相、古环境及古地理特征,综合分析认为云龙县—兰坪县一带含盐系地层具有优越的钾盐成矿前景。
Though the analysis of major and trace elements of the Paleogene saline clay-argillaceous siltstone-siltstone samples collected from field outcrops in Lanping basin, palaeosalinity character of these regions was revealed by quantitative, semiquantitative method involving calculation using Adams and Couch palaeosalinity formula, equivalent boron determination suggested by Walker and strontium-barium ratio. The results indicate the palaeosalinity changes obviously, in the range of 6.5‰～22.05‰, and display that the majority of samples show semisaltwater sedmientary environment, while freshwater environment is secondary. The sedimentary center is mainly distributed in Yunlong and Lanping County with higher paleosalinity values. In plane view, the paleosalinity values debase as far away from the sedimentary center to the peripheral basin, and its associated sedimentary environment show good corresponding relation. According to the basin sedimentary facies, paleoenvironment and paleogeographic characteristics, the au- thors consider that the salt-bearing stratum of Yunlong-Lanping County has a superior potassium metallogenic prospect.
出处
《盐湖研究》
CSCD
2016年第3期8-16,共9页
Journal of Salt Lake Research
基金
国家自然科学基金项目(41362008
U0933605)
江西省教育厅科技项目(GJJ14475)联合资助
关键词
兰坪盆地
钾盐
古盐度
硼元素法
Lanping basin
Potassium
Palaeosalinity
Boron element method
