Definition of whole zone apparent resistivity for transient electromagnetic method of current dipole source

A new scheme to define all time apparent resistivity is introduced.For this method,the solution of a nonlinear monotone function,which is very common in electromagnetic soundings,is obtained via continued fraction iteration technique.Numerical results for layered earth show that the new method can be successfully applied to the definition of all time apparent resistivity which can reflect the real variation of geoelectrical section.