Key Issues and Application Cases of NMR Logging While Drilling

Described are NMR LWD technology and its applications.NMR LWD has advantages of providing real-time information for un-invaded formations,logging in high angle and horizontal wells,and geosteering.Compared with wireline NMR logging,NMR LWD is performed in more hostile environment.The key features and investigation characters of NMR LWD tool for adapting complex motions during drilling are discussed.Application results proved reliability of these tool's and good agreement with wireline NMR logging reference,and they can provide necessary information for time-elapse logging method.At last,given are some suggestions on future development of NMR LWD in China,for example,study the probe design scheme and make numerical simulation;make physical experiments about the probe designs and make a simulated device under the drilling condition in the lab to test the key technology of the probe;and select the most optimized design scheme to build up a complete NMR LWD system and test it in field operation.