Understanding the Impact of Channel Fracturing in the Eagle Ford Shale Through Reservoir Simulation

摘要

Oil and gas production from unconventional reservoirs has witnessed significant growth in the last few years. Historically, massive stimulation treatments have been used to produce these hydrocarbons. While the in-place hydrocarbon volumes are often large, the challenge is to increase recovery while using fewer resources. One of the technologies that have been used to address this challenge is the channel fracturing technique. A number of horizontal wells have been stimulated in the Hawkville field of the Eagle Ford shale with this technique. The objective of this work was to evaluate the impact of the channel fracturing technique in these wells by using numerical reservoir simulation. Numerical simulations were performed on a total of 15 horizontal wells. Six wells were completed with channel fracturing and nine wells were completed with slickwater or hybrid fracturing treatments. Because the Hawkville field has large variations in fluid composition, wells producing in the condensate-rich section were studied separately from those in the dry gas section. A consistent history matching methodology and workflow was applied across all wells which enabled a direct comparison of results. Results from analytical work, such as normalized production comparisons, were used to narrow down the range of uncertainties and assumptions made in the numerical simulations. A trend emerged from the analytical evaluations, showing that wells completed with the channel fracturing technique have higher productivity while using significantly less proppant and fracturing fluid. Numerical simulations confirmed the finding and provided insights on the cause of higher production on these wells. Unlike analytical methods, numerical simulation can model changes in complex fracture properties between wells, the effects of transient flow, shale gas desorption from kerogen, interference effects between perforation clusters, and accounts for differences in shale reservoir quality between wells. Furthermore, calibrated well models allowed for sensitivity studies such as evaluating the impact of changes in fracture geometry and conductivity on future wells. Reservoir modeling provided an estimation of effective stimulated fracture volume and fracture conductivity. Wells treated with the channel fracturing technique were observed to have on average 50% greater effective stimulated volume and more than double the stimulated conductivity compared to wells fractured with slickwater. When compared to wells fractured with hybrid treatments, channel fracturing wells had on average 27% greater effective stimulated volume and 50% more stimulated conductivity.