Electromagnetic modeling of wave propagation in curved boreholes for geophysical exploration

Abstract

Logging-while-drilling (LWD) tools are routinely used to guide well placement during exploration of hydrocarbons reservoirs. Recent advances in the drilling technologies have allowed real-time proactive geosteering of the drilling direction to steer to a precise target zone. Electromagnetic modeling of LWD sensors in complex geometries is a challenging task to conventional computational electromagnetics (CEM). In particular, several complications arise due the non-conformal boundaries present in this problem. In this paper we present a pseudoanalytical formulation to handle the electromagnetic wave propagation inside radially-stratified and axially-toroidal structures that could be used as an efficient CEM method for modeling LWD tools inside directional boreholes. Preliminary results demonstrate that our method can accurately analyze LWD sensors in typical directional wells.