Well Configurations in Anisotropic Reservoirs

TLDR

Horizontal wells enhance productivity but require accounting for permeability anisotropy and the possibility of multiple horizontal drainholes from a single vertical well. The study introduces solutions for arbitrarily oriented single or multiple horizontal wells. These solutions are derived by extending well‑known existing relationships to accommodate arbitrary orientations. The authors present performance relationships for key well configurations, highlighting early‑ and late‑time differences beyond bounded flow regimes.

Abstract

Summary Horizontal wells have emerged as a new means for well-productivity enhancement. Simultaneously, they have brought forward the need to recognize and account for permeability anisotropies, including vertical-to-horizontal and horizontal-to-horizontal directions. In addition, there is the possibility of multiple horizontal drainholes emanating from the same vertical well. Performance relationships for the most interesting well configurations are presented, including both early-time and late-time differences rather than only bounded flow regimes. Solutions for arbitrarily oriented single or multiple horizontal wells are introduced, along with a discussion of well-known existing relationships.