Horizontal Well Placement and Completion Optimisation in Carbonate Reservoirs

Abstract

AbstractHorizontal wells provide increased reservoir contact than conventional vertical wells but present another set of production challenges particularly with respect to imbalanced fluid inflow along the wellbore. This paper will describe the importance of wellbore and reservoir characterization, modelling and practical operational experiences to maximize recovery in a carbonate environment using logging while drilling (LWD) measurements to design reliable and effective completion equipment to manage production. Due to the fractured nature of carbonates and high heterogeneity contrast with the matrix, it is imperative to balance inflow and delay the production of more mobile fluids through the installation of passive inflow control devices (ICD) and swellable packers. Near wellbore steady state and numerical reservoir simulation is particularly important for preliminary design and justification of completion technology. The latter can indicate regions of by-passed oil and areas of high water saturation providing horizontal well infill opportunities. The analysis of real time LWD is essential for well placement but also the characterization of the near wellbore to identify areas of high fracture density and where fluid losses have occurred, to design an appropriate completion tally to maximize production. The availability of adjustable ICDs at the wellsite offers the opportunity to perform this task to fine tune the lower completion design before running in hole. The modelling workflow and operational procedures of optimizing well placement and ICD completion design will be described through carbonate field installations.