Prevention of disasters due to the chemical compositions of the rocks in the slope failures damaged by the Hyogoken-Nanbu Earthquake

许多陡坡在兵库县南部地震中严重受损。神户地区的陡坡受到断层的强烈作用，风化得很深。降雨期间塌方已蔓延。认为该地区边坡失稳集中的原因是严重的破碎和风化作用。该元素在边坡失稳的风化过程中从岩石中浸出。在此过程中岩石中的MgO、Cao、Feo含量显着降低。这些元素的浸出在黑云母中是显着的，因为黑云母在水的存在下转变为蛭石和高岭石。斜坡中岩石的化学成分反映了风化程度。因此，化学成分对于防止斜坡破坏是有用的。斜坡失稳似乎集中沿矿脉。斜坡上的花岗岩被认为是在热液作用下蚀变成粘土矿物的。花岗岩中的黑云母很容易风化，并在水的存在下转变为粘土矿物。边坡破坏与花岗岩边坡中的脉体有着密切的关系。

Many steep slopes were heavy damaged by the Hyogoken-Nanbu Earthquake. The steep slopes in Kobe district has been so strongly by the fault and been weathered deeply. The collapse has been spread during the rainfalls. The reason for the slope failure concentration is thought to be heavy crushed and weathering in this area. The element are leached from the rocks during the wethering process of the slope failure. MgO, Cao and Feo contents in the rocks are remarkably decrease during the process. Leaching of these elements is remarkable in biotite, because the biotite alters in the presence of water to vermiculite and kaolinite. Chemical composition of the rocks are in the slope reflect to weathering grade. Thus, chemical composition are useful for prevention of the slope failures. The slope failures appear to be concentrated along the vein. The granitic rocks of the slopes are thought to be alteration to clay minerals at hydrothermal. Biotite in granitic rocks is easily weathered and alters in the presence of water to clay minerals. There is a close relation between slope failure and the vein in the granitic slopes.