3C reflection from crack layers - synthetic seismograms

摘要

In comparison with RLI (the reflection from litho-logical interface) , this paper suggests an idea of RCL (the reflection from crack layers). We have calculated three-component seismograms for horizontally layered media in different azimuths. For the layer containing cracks with different densities, saturation and dipping angles, the results show that the reflection P-wave and PS-wave can have the amplitude nearly e-qual to that of RLI. It is difficult to identify RCL and RLI only from P-wave reflections. But in contrast with PS-wave splitting, the crack layer could introduce visual polarization anomaly of PS-wave on two horizontal components that may be the indicators used to recognize crack layers. In this paper, we also trust that, whether the crack has a dipping angle or not, it could be recognized by comparing P-waves and PS-waves in opposite directions.