Parameter optimization study of three-dimensional well network-fracture network coupled fracturing in jimsar shale oil

Abstract

The exploration of sweet spots in the Jimsar shale oil reservoir in Xinjiang involves creating a complex fracture network through three-dimensional well networks and advanced fracturing technology, crucial for successful shale oil reservoir development. However, the extremely low permeability of shale oil and limited natural flow capacity of crude oil pose significant challenges. The interconnection between three-dimensional well networks and artificial fracture networks, and the relationship between fracturing parameters and fracture morphology, remain unclear. This study focuses on the P2l12−2 and P2l12−3 layers of the Lucaogou Formation. Utilizing the Petrel geological engineering integrated platform and the Kinetix fracturing module, we conducted numerical simulations to explore coupled fracturing in different sweet spots, with a specific emphasis on well network and fracture network coupling. This study identified relevant optimized engineering parameters. Research findings indicate that, during single-well single-factor optimization, the viscosity optimization range for Class II reservoirs is smaller compared to Class I reservoirs. However, for other factors such as injection rate, liquid volume, proppant concentration, cluster count, etc., the optimization ranges are greater for Class II reservoirs than for Class I reservoirs. In the case of single-factor optimization for well networks, increasing well spacing leads to larger optimization ranges for proppant concentration and perforation numbers. Under the same well spacing, an alternating wellbore arrangement results in a smaller optimization range for proppant concentration but a larger range for perforation numbers compared to a directly opposite wellbore arrangement. Additionally, this paper summarizes the optimization ranges and provides relevant tables and figures, aiming to offer guidance for on-site construction.