随钻多模式电阻率成像测井仪响应的三维有限元数值模拟

作者：康正明,柯式镇,李新,米金泰,倪卫宁,Li Ming-Yu

摘要：A new multi-mode resistivity imaging sonde,with toroidal coils as source,can conduct three resistivity measurements:azimuthal resistivity,lateral resistivity,and bit resistivity measurements.Thus,the logging time and cost are greatly saved.The toroidal coils are simplified as an extended voltage dipole and the response equations are derived for a homogenous formation.Based on 3D FEM,the depth of investigation(DOI),vertical resolution,circumferential azimuthal capacity,borehole diameter,mud resistivity,thickness of target formation,and the resistivity of the surrounding formation and mud invasion are simulated.The results suggest that the three measurement modes of the new sonde are different in vertical resolutions and DOIs.The circumferential detection ability of the azimuth button depends on the contrast between the anomaly and formation resistivity and the open angle of the anomaly.Whether the borehole is truncated at the bit or not has a great infl uence on the simulation results.The borehole and mud invasion affect the apparent resistivity in all modes,but the effects of resistivity of surrounding formation and thickness of the target formation are only corrected for lateral resistivity measurement.

发文机构：College of Geophysics and Information Engineering State Key Laboratory of Petroleum Resources and Prospecting Sinopec Research Institute of Petroleum Engineering

关键词：3DFEMLWDMULTI-MODERESISTIVITYimagingdetectioncharacteristicsENVIRONMENTALeffects

分类号： O[理学]