关于风化作用涵义的探讨  

The Discussion on the Meaning of the Weathering

作　　者：廖士范 

机构地区：[1]贵州省地矿厅,贵阳550004

出　　处：《贵州地质》1997年第1期64-70,共7页Guizhou Geology

摘　　要：风化作用是指受太阳能，大气、大气水影响的地球物理、地球化学、生物化学的综合作用，使一部分物质溶解淋失，另一部分物质残留；低价元素矿物氧化成高价元素矿物，形成氧化带（风化带）。过去只知道其范围只包括"暴露在地表面"这一部分，没有包括地表面以下的"氧化改造带"。由于两者都是大气水（天水）组成，其物、化性质相同，都含游离CO2、O2气体，从地球化学的意义来说，实际是在酸性条件下的氧化作用。这种大气水中除了含有游离的CO2、O2气体之外，一般还溶解有H+、HCO_3^-、HSO_4^-离子、络合离子，有时还含有有机酸离子，各种盐类离子、络合离子，这种化学条件下都能进行风化作用。所有风化矿产受其影响向下都达到"氧化改造带"，个别情况下甚至还影响其以下的"还原成矿改造带"。地表面与地下"氧化改造带"两者风化作用所需要的各项条件也相同，所以风化作用就其涵义来说其范围除过去所知包括"暴露在地表面"这一部分之外，还应包括"氧化改造带"这一部分。The weatering is an integrative process of geochemistry, geophysics and biochemistry under the influence of solar energy, atmosphere and meteoric water. In the weatering, a part of materialls is disolved and leached away, whereas the others reside, of which the minerals containing lower-valence elements are oxidized,forming oxidized zone (weathered zone). It was previously known that the range of the weathering included only the part exposed on the surface, not the other part-'oxidized and reworked zone' below the surface. Because the both contain meteoric water with free CO2 and O2, their physical and chemical properties are the same. Geochemically, the oxidization is actually to occur under acid condition (pH>7). In addition to free CO2 and O2, the meteoric water contains dissolved H+,HCO_3^-, HSO_4^(2-), sometimes organic acid ions, various kinds of salt ions and complex ions, all of which can be involved in the weathering.All of weathered mineral deposits, not only at surface, but also below surface, are influenced by the weathering to reach to the 'oxidized and reworked zone', and individually, even to the 'reduced and rewoked ore - forming zone'done. The conditions for forming surface and subsurface'oxidized and rewoked zones' are the same. Therefore, for the meaning,the range of the weathering should include both the known previously part'exposed at the surface' and the part, 'oxidized and reworked zone

关 键 词：风化矿床 风化作用 还原成矿带 氧化改造带 

分 类 号：P611.21[天文地球—矿床学]