Comparative Study On Wave Field Separation Methods In Array Acoustic Logging

The wave field separation is a part of array acoustic logging data processing andinterpretation. Array acoustic field provides lots of formation information, such as slowness,permeability, fracture and so on. Array acoustic field contains different mode waves withdownhole noises, so wave filed separation and noise elimination must be did in order to getkinds of wave filed which can reflect formation information.How to choose an effective separation method according to the complex wave field is akey problem.The paper has done detailed study on wave field separation and analysed sevralcommonly employed wave field separation methods, such as median filter, f-k filter, radontransform, speed offset method and so on. It verified these methods from theoretical modeland log data. The paper focused on comparing different methods and studying characteristicsof each method. In the end one wave separation software is developed for data processing andapplication. Some content includes:1. A detailed study on the theory of field wave separation has been done, which providstheoretical analysis basis.2. The circuit of wave field separation is diaplayed, including raw data pre-processing,one-dimensional filter, slowness extraction, wave field separation which improved processingprecision.3. This paper has studied separation methods detailedly, sunch as the advantage anddisadvantage, influencing factors, applicable conditions, parameter selection, also analysedtheir differences and results with theoretical simulation and log datas.4. Wave field separation processing software has been developed on Netbeans platformby Java and field datas are processed.The reliability of software is confirmed after comparingthe result with that of foreign professional software, also the differences between the differentprocessing methods has been found out.5. A preliminary research on the application of wave field separation has been done.