A NEW APPARENT RESISTIVITY OF WIDE FIELD ELECTROMAGNETIC DEFINED BY E-Eφ & E -ExCOMPONENT
WANG Qi1, WANG Hong-yu1,2, CHENG Dang-xing3,4
1. North-west Mining and Geology Group CO., LTD for Nonferrous Metals, Xi'an 710054, China; 2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China; 3. Exploration & Development Research Institute, Changqing Oilfieid Company, PetroChina, Xi'an 710018, China; 4. National Engineering Laboratory for Exploration and Development of Low-Permeability Oil & Gas Fields, PetroChina, Xi'an 710018, China
Abstract：Using the electromagnetic fields of a horizontal electric dipole electric component expression, this paper discussed the Ex and Eφ components which have different amplitude ranges, and propose a new apparent resistivity of wide field electromagnetic defined by Eφ component. The authors also studied the characteristics of the apparent resistivity of wide field. Under the condition of the homogeneous half space, the measurement of Eφ components can expand the field observation sector and reduce the construction cost. Through studying the two-layer model of the forward theoretical curves, the authors have found that the wide field apparent resistivity defined by Eφ component has much smaller observation angle than Ex mode, corresponding to the observed sector where no apparent resistivity curve distortions occur. By calculating apparent resistivity defined by wide field Eφ component of type H and type K model, the authors have found that wide field electromagnetic method is more sensitive to low resistance. The numerical results show that the wide field electromagnetic method also has the near-zone.
王启, 王宏宇, 程党性. E-Eφ、E-Ex广域视电阻率对比与应用[J]. 物探与化探, 2014, 38(1): 120-124.
WANG Qi, WANG Hong-yu, CHENG Dang-xing. A NEW APPARENT RESISTIVITY OF WIDE FIELD ELECTROMAGNETIC DEFINED BY E-Eφ & E -ExCOMPONENT. Geophysical and Geochemical Exploration, 2014, 38(1): 120-124.
