多层状碳酸盐岩岩溶发育基本模式及其在水利工程中的应用实例

我国西南近代地壳抬升区的多层状碳酸盐岩岩组常被河流深切割。被河流深切割的这些多层状碳酸盐岩岩组其岩溶发育特征对水利水电工程建设具有重大的影响。受岩性的控制,多层状碳酸盐岩岩组的溶蚀作用一般仅在碳酸盐岩岩层内进行,岩溶顺层发育成多层状,在无特殊条件破坏情况下,层间非碳酸盐岩岩层成为相对隔水层,是水库防渗的良好依托;但一些张性、扭性断裂的切割作用或是层间非碳酸盐岩岩层塌陷,都可能导致层间隔水层遭受破坏,使岩溶出现穿层发育现象,对水库防渗极为不利。因此,在水库防渗设计中应特别注意是否存在层间渗漏缺口及其影响问题。 

Models of karst development in multilayered carbonate rock andapplication in hydro-engineering

Many multilayered carbonate rocks are deeply cut by rivers at crust newly uplift area in Southwest China. Karst development of the deeply cut multilayered carbonate rocks affect significantly to water and hydro-power projects. It is proved that the corrosion, controlled by lithology, is going on only along carbonate rocks layer and therefore the karst development is multilayered, and the non-carbonate rocks layers are good confining bed, which is very efficient to anti-seepage if they are not destructed. However, the dissections of tension faults or shear faults or collapses between layers may breach the confining bed, which leads to karst develops from one carbonate rock layer to another and is very unfavorable to the reservoir＇s anti-seepage. So, much attention should be paid to the existence of gaps in confining beds and their influence on seepage.