Optimization of Infill Drilling in Whicher Range Field in Australia

Abstract

Abstract Now that most of the conventional reservoirs are being depleted at a rapid pace, the focus is on unconventional reservoirs like tight gas reservoirs. Due to the heterogeneous nature and low permeability of unconventional reservoirs, they require a huge number of wells to hit all the isolated hydrocarbon zones. Infill drilling is one of the most common and effective methods of increasing the recovery, by reducing the well spacing and increasing the sweep efficiency. However, the problem with drilling such a large number of wells is the determination of the optimum location for each well that ensures minimum interference between wells, and accelerates the recovery from the field. Detailed 3-D numerical reservoir modelling is the most trusted method to determine the optimum locations of the infill wells, but it is time consuming and expensive. Therefore, the industry is on the lookout for methods that are fast and effective. Over the last few decades, researcher have come up with techniques like moving window, rapid inversion, Infill Well Locator Calculator (IWLC) etc. for infill drilling optimization of tight resources. In this paper reservoir simulation modelling was combined with the Moving Window Method (MWM) to develop an optimum infill-drilling plan for Whicher Range (WR) Tight-gas Field in Western Australia. The accuracy and effectiveness of developed optimum plan are justified through comparative studies using standard reservoir simulation model; which demonstrates that the proposed plan effectively predicts the optimum number of wells including the production rate of each wells similar to that obtained from standard reservoir simulation studies. It is also inferred that reservoir simulation combined with MWM requires less data and much simpler as well as faster compared to standard reservoir simulation for optimizing an infill drilling plan for alike of Whicher Range tight gas field.