Multiwave sonic log – the precision tool for cracks study

The development of multi-channel sonic logging devices with the ability to induce directional shear<br>waves, on one hand, allows us to increase the accuracy of standard measurements, such as dynamic and<br>kinematic parameters of different types of waves, but on other hand gives us the possibility to study the<br>fractural porosity and formation stress both in open hole well and in cased one. Information about cracks<br>orientation, its aspect ratio and formation stress direction is useful for optimization of oil and gas production<br>and needed by specialists of oil companies. Industrial necessity makes us to develop the technology of<br>multiwave sonic log analysis at shortest terms. The paper shows some theoretical and methodological aspects<br>of data processing and interpretation. Reliability of obtained data is also discussed.