Research and Application of Reflected Acoustic Wave Data Processing Method While Drilling

When the technology of remote detection acoustic logging while drilling is used for boundary detection, in order to extract formation interface information from reflected acoustic wave data, a reflected acoustic wave data processing method while drilling(RAPM) is studied. Remote detection acoustic logging while drilling uses reflected acoustic wave to detect formation interface, the waveforms recorded by receivers include wellbore direct wave, reflected acoustic wave, and drilling tool vibration noise, which have the characteristics of strong wellbore direct wave and weak reflected wave. A wave field separation method based on slowness time coherence and median filtering is constructed to filter out wellbore direct wave from the received waveform. By migration stack imaging technology, the remaining reflected acoustic wave after filtering are imaged to obtain information about the reflection interface. A numerical simulation is conducted on the acoustic propagation of a wellbore model containing formation interface. Using this data processing method, multiple components of direct wave such as compressional wave, shear wave, and stoneley wave are successfully separated, and the direct wave are filtered out from the received waveform. A acoustic wave remote detection experiment is conducted in pool, successfully collecting reflected acoustic wave data, completing reflected acoustic wave data processing and imaging, and identifying the reflection interface at a radial distance of approximately 8.00m. RAPM enables reflected wave extraction and formation interface imaging, which provides technical support for the application of remote detection acoustic logging while drilling to geosteering.