石灰岩变形模式的讨论

在三轴压力和10~(-4)/秒的应变速率下,对广西苹果石灰岩分别进行了压缩试验和摩擦实验,确定了两种变形模式。据此推测,石灰岩在地壳岩石的深度条件下、完整石灰岩的不稳定破坏可能发生在5公里以上;粘滑破坏可能发生在8-13公里之间;其他的深度变形都是稳定的或准稳定的,深度大于20公里,断层的存在已没有任何意义。

A DISCUSSION OF DEFORMATION MODEL OF PINGGUO LIMESTONE

Pingguo Iimestons was studied experimentally under triaxial stress and strain rate of 10~(-4)/S. For intact limestone:the brittle failure field is below confining pressure(Pc)of 150 MPa,the ductile flow field is above 200 MPa the brittle-ductile transition is between 150-200 MPa. For sawcut limestone:the stable sliding field is below 200 MPa, stick-slip failure field is between 250-380 MPa,above 400MPa is another stable deformation field.Below and above the stick-slip field,There are two transitions to stable sliding field at both ends of the stick-slip field. Presumably,the unstable failure of intact limestone occurs only at depth less then 5 km,the stick-slip failure may occur between 8-13 km. In other crustal depth,the deformation of limestone is always stable or quasistable.The presence of fault has no any significance below depth of 20 km.