Real-time geosteering technology plays a key role in horizontal well development, which keeps the wellbore trajectories within target zones to maximize reservoir contact. Deep-directional-resistivity logging while drilling (LWD) tools have longer detection range and directionality to provide sufficient information for the operators, but meanwhile bring challenges to inversion of logging data, especially when the number of model layers is not fixed in priori. In this paper, we have developed an automatic inversion method to include the number of layers as a variable based on the trans-dimensional Markov chain Monte Carlo (MCMC) algorithm. The method assumes a 1D model based on planar layered formations penetrated by arbitrary well trajectories. In addition, a synthetic example demonstrates the inversion method can efficiently estimate the number of layers, positions, resistivities and also provide the probabilities of parameters without introducing bias.
Presentation Date: Wednesday, October 17, 2018
Start Time: 1:50:00 PM
Location: Poster Station 10
Presentation Type: Poster