摘要
以黔中平坝剖面为具体对象,从矿物、元素地球化学、元素质量平衡等多方面对黔中白云岩上覆红粘土剖面进行了详细研究。结果显示该剖面是下伏基岩白云岩风化成土并累积的结果,无其他外来物源,是原位风化壳;成土过程具有两阶段模式特征,即白云石、方解石的溶蚀-酸不溶物累积和酸不溶物进一步风化两个阶段;长时期的构造稳定和白云岩整体溶蚀作用是黔中地区白云岩风化壳土层厚度大、分布连续的主要制约因素。
This paper presents the mineral compositions, the contents of Al2O3 and Zr, TiO2/Al2O3 and Fe2O3 T/Al2O3 ratios, SiO2/Al2O3 and K2O/Na2O ratio, the ratios of mobile to immobile elements （Ca/Al, Mg/Al, Na/Al, K/Al and Mn/Al） and between the immobile elements （Al/Zr, Ti/Zr and Ti/Nb）, gains or losses of the major elements along the weathering profile of Pingba red residua on the karst terrains of centrl Guizhou, the teconic characteristics of this region, and the weathering characteristics of dolomite. The results demonstrate that the Pingba red residua is a typical in situ chemical weathering crust, and the material sources of the profile are derived from underlying Triassic dolomites, the chemical weathering of dolomite can be divided into two stages： ＂leaching-accumulating trend＂ and weathering trend＂, the stable teconic and whole weathering of dolomite should be the main reason for the development of thick and consecutive red weathering crust overlying dolomite rock in central Guizhou.
出处
《矿物学报》
CAS
CSCD
北大核心
2006年第3期249-256,共8页
Acta Mineralogica Sinica
基金
中国科学院创新团队国际合作伙伴计划和前沿领域项目
国家自然科学基金(批准号:40371012)
关键词
红粘土
物质来源
成因
平坝剖面
黔中
weathering crust of dolomite rock, material source
genesis, Pingba profile.
