【作者】 庞巧；

【导师】 王建力；

【作者基本信息】 西南大学 ， 第四纪地质学， 2009， 硕士

【摘要】 通过元素地球化学特征研究,得出长江三峡巫山地区第四纪沉积物7种常量元素中,以CaO、Na₂O变化系数显著大于其它四种Al₂O₃、Fe₂O₃、K₂O、MgO常量元素,这与西北黄土一样,而与长江漫滩沉积物相比,各常量元素的变化系数相差较大。老巫山师范剖面比望天坪剖面常量元素变化系数小,老巫山师范常量元素的组成较望天坪常量元素组成总的来说要均一得多。巫山地区第四纪沉积物中老巫山师范3号剖面与西北黄土常量元素氧化物的变化趋势大致是一致的,都有富铝、富铁和富钙的现象,望天坪1号剖面、望天坪表土、疗养院和疗养院表土有显著的富铝和富铁现象。巫山地区第四纪沉积物10种微量元素的变化在各个剖面上体现出了差异性。老巫山师范3号剖面10种微量元素变化系数均小于望天坪1号剖面的10种微量元素变化系数,说明老巫山师范在微量元素组成上比望天坪均一。通过对比老巫山师范和西安黄土微量元素变化系数,得出老巫山师范和西安黄土微量元素变化系数都很小,说明它们组成十分均一。各表土层变化系数都不是很大,说明表土层微量元素组成均一,这可能是人类农业活动所造成的。可以根据相对偏差大小初步认为老巫山师范沉积物与西安黄土在物质组成上接近。望天坪1号剖面CIA值明显高于老巫山师范3号剖面,相比较而言,老巫山师范3号剖面CIA值更接近于长江漫滩沉积物。同时也说明老巫山师范3号和望天坪1号剖面在风化之初具有不同的化学组成,也反映它们在形成时经历的化学风化程度不同,老巫山师范3号剖面明显弱于望天坪1号剖面。更多还原

【Abstract】 By geochemistry characteristics analyses, several results are concluded in WuShan district of Three Gorges. Compositions of 6 major elements are different, the CV of CaO、Na₂O are bigger than Al₂0₃、Fe₂O₃、K₂O、MgO in WuShan district, it has the same result as XiBei loess while has a differentiation compared with ChangJiang sediments. Composition of major elements in Old WuShan school sediments are homogeneous than WangTianPing’s from the analyses of CV. Old WuShan school sediments has the same variability trend as XiBei loess in accumulation of Al、Fe、Ca, while others profiles have the notable accumulation of Al、Fe. Compositions of trace elements have distinctive variabilities in each profiles. Old WuShan school sediments is homogeneous than WangTianPing’s in 10 trace elements. By the comparision of trace elements ,results show that Old WuShan school sediments has the same homogeneous composition as Xi’an loess . Due to the effect of agricultural activities ,trace elements in surface soils are homogeneous . The preliminary result shows that Old WuShanschool sediments are similar as Xi’an loess. The CIA value in WangTianPing sediments is higher than Old WuShanschool’s, which is near to the ChangJiang sediments. This shows the different chemical components in the beginning weathering between WangTianPing and Old WuShan school, and the different weathering trendency which means Old WuShan school is weaker than WangTianPing.更多还原