Optimal well spacing density in channel sandstones in the case of Ozen field

Most of Kazakhstan’s oil fields are mature ones. However, wells are still drilled in these fields (annually ~ 500 wells in JSC NC “KazMunayGas”). Well drilling forms a certain well spacing density at the fields.

This article is concerned with the influence of well spacing density on the oil recovery factor in channel sandstones. The problem of how well spacing density (WSD) influences oil recovery factor (ORF) is one of the most studied and debated in forecasting oil production levels. In the course of studying existing scientific works on this topic, we understood that there is no uniform function of well spacing density and oil recovery factor. Today, when developing a field, it is relevant to search for new approaches to choose the optimal WSD taking into account all aspects of the geological structure based on hydrodynamic modeling. This article provides verification for the optimal WSD in channel sandstones choosing as an example sector model of horizon 13 of the Ozen field in two stages.

During modeling we analyzed the current conditions of field development, and identified WSD with high values. Then a list of highly watered (unprofitable) wells was identified and recommended for shutdown. According to simulation, it is possible to maintain the base level of oil production by shutting off high water cut wells thereby decreasing well spacing density and optimizing fluid production on the remaining stock.