Study On Azimuthal Electromagnetic Resistivity Logging While Drilling

At present,with the gradual exploiting of unconventional reservoirs and offshore oil fields,the difficulty of oil and gas exploration has increased.The logging while drilling technology has played an important role nowadays.The azimuthal electromagnetic resistivity logging while drilling has been extensively applied to the exploration of oil and gas because of its particular advantages of geosteering function and formation evaluation.In this paper,we learn the theory of azimuthal electromagnetic resistivity logging while drilling,and then systematically research its depth of investigation and azimuthal signal by numerical simulation method.Firstly,we research and summarize the basic theory of the azimuthal electromagnetic resistivity logging while drilling by comparison with the conventional technology and then define the azimuthal signal and depth of investigation again.Next,we use the Fast Hankel Transform(FHT)method to calculate the electromagnetic field in horizontal layered formations exactly and fleetly.Finally,we research and then get the effect of instrument parameters and environmental factors on the depth of investigation and the azimuthal signal by the above forward modeling.And the research result is instructive for the next instrument parameter optimization and signal processing.