An axisymmetric finite difference method is employed for the simulations of electromagnetic telemetry in the homogeneous and layered underground formation.In this method,we defined the anisotropy property using extens...An axisymmetric finite difference method is employed for the simulations of electromagnetic telemetry in the homogeneous and layered underground formation.In this method,we defined the anisotropy property using extensive 2D conductivity tensor and solved it in the transverse magnetic mode.Significant simplification arises in the decoupling of the anisotropic parameter.The developed method is cost-efficient,more straightforward in modeling anisotropic media,and easy to be implemented.In addition,we solved the integral operation in the estimation of measured surface voltage using Gaussian quadrature technique.We performed a series of numerical modeling of EM telemetry signals in both isotropic and anisotropic models.Experiment with 2D tilt transverse isotropic media characterized by the tilt axis and anisotropy parameters shows an increase in the EMT signal with an increase in the angle of tilt of the principal axis for a moderate coefficient of anisotropy.We show that the effect of the tilt of the subsurface medium can be observed with sufficient accuracy and that it is an order of magnitude of 5 over the tilt of 90 degrees.Lastly,consistent results with existing field data were obtained by employing the Gaussian quadrature rule for the computation of surface measured signal.展开更多
Hydrocarbon exploration has evolved over the years from shallow subsurface to deep subsurface prospecting in both onshore and marine environment.In accordance,technical development has encouraged exploration of unconv...Hydrocarbon exploration has evolved over the years from shallow subsurface to deep subsurface prospecting in both onshore and marine environment.In accordance,technical development has encouraged exploration of unconventional reservoirs and development of deeply buried ones.The deeply buried carbonate reservoir in the Tarim Basin have attracted considerable attention(Lee,1985;Neil,1997;Jin et al.,2009,2015).Such deeply buried reservoirs requires careful and accurate well landing and borehole navigation through multiple regions of HC accumulation and precise well closing process involving accurate selection of positions for screens and so on.展开更多
文摘An axisymmetric finite difference method is employed for the simulations of electromagnetic telemetry in the homogeneous and layered underground formation.In this method,we defined the anisotropy property using extensive 2D conductivity tensor and solved it in the transverse magnetic mode.Significant simplification arises in the decoupling of the anisotropic parameter.The developed method is cost-efficient,more straightforward in modeling anisotropic media,and easy to be implemented.In addition,we solved the integral operation in the estimation of measured surface voltage using Gaussian quadrature technique.We performed a series of numerical modeling of EM telemetry signals in both isotropic and anisotropic models.Experiment with 2D tilt transverse isotropic media characterized by the tilt axis and anisotropy parameters shows an increase in the EMT signal with an increase in the angle of tilt of the principal axis for a moderate coefficient of anisotropy.We show that the effect of the tilt of the subsurface medium can be observed with sufficient accuracy and that it is an order of magnitude of 5 over the tilt of 90 degrees.Lastly,consistent results with existing field data were obtained by employing the Gaussian quadrature rule for the computation of surface measured signal.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(NO.XDA140500001)
文摘Hydrocarbon exploration has evolved over the years from shallow subsurface to deep subsurface prospecting in both onshore and marine environment.In accordance,technical development has encouraged exploration of unconventional reservoirs and development of deeply buried ones.The deeply buried carbonate reservoir in the Tarim Basin have attracted considerable attention(Lee,1985;Neil,1997;Jin et al.,2009,2015).Such deeply buried reservoirs requires careful and accurate well landing and borehole navigation through multiple regions of HC accumulation and precise well closing process involving accurate selection of positions for screens and so on.
