大巴山区早古生代地层和石煤中硒的化学活动性的初步研究

通过对大巴山区主要分布的早古生代地层中的碎屑岩，碳酸盐岩和石煤的原岩，风化岩，原生土壤的硒含量及其相关关系分析，及对南秦岭早古生代地层和石煤中硒的化学活动性进行了研究。结果表明：其岩石和石煤中的硒在地层环境下有较大的活动性，不同类型岩石中硒淋失率和硒的淋失量不同，富硒而淋失率低但淋失量高的下寒武统鲁家坪组和早志留世大贵坪组的炭质板岩和石煤的分布区土壤（主要为当地岩石的风化残积物）的含硒量可达10mg/kg，甚至更高，是大巴山的富硒带和硒中毒带，含硒低而且淋失率高的志留系砂岩和粉砂岩以及寒武系统砾屑灰岩分布区是大巴山区的低硒带。

Chemical mobility of selenium in early paleozoic rock and stone coal in Daba Mountain, South Qinling

By studying the relation of selenium between the rock and stone coal with their weathering rock and original soil of early Paleozoic Period in Daba Mountain and combining the dripping and leaching experiment, the chemical mobility of selenium in the rock and stone coal of early Paleozoic in Daba Mountain was investigated. The results demonstrate that inobility of selenium in the rock and stone coal of early Paleozoic in Daba Mountain have a high mobility at surface conditions, and the leaching retes are different in various kinds of roeks.In the distributing area of the special carbonaceous shale and stone coal of Lower Silurian and Lower Cambrian, the selenium contents reach to10 mg/kg and even more but the leaching rate is low. This area is the zoster of selenium intoxication or selenium abundant. The distributing area of sandstone and siltstone of Silurian as well as calcirudite of Cambrian is the low selenium zoster in Daba Mountain.