Fracture propagation simulation and construction parameter optimization of eruptive phase volcanic rock

A large number of volcanic gas reservoirs are developed in the Sichuan Basin. Up to now, 92 wells have been drilled into Permian volcanic rock, which have good prospects for exploration. Among them, large areas of volcanic facies are distributed in the Sichuan Basin. The uneven distribution of pores in volcanic rocks of eruptive facies and the large difference in rock mechanics combination between different lithofacies make it difficult to develop volcanic gas reservoirs of eruptive facies effectively. Therefore, studying the characteristics of eruptive facies volcanic rocks and reservoir reconstruction schemes is very important for the later development of volcanic rocks Significantly, this paper builds a finite element model of a volcanic rock reservoir of the effusion facies based on the geological characteristics of the volcanic rock of the effusion facies, and optimizes the construction parameters in terms of construction displacement, fracturing fluid volume, and proppant. The research results show that, the injection pressure of the spouting phase under different stress difference conditions exhibits oscillating characteristics. The stress difference between the barrier and the reservoir is positively related to the injection point pressure and fracture fracturing. The recommended construction displacement is 4.5-5.5m³/min and the fracturing fluid dosage is 400-500m³, and the amount of proppant is between 30-40m3. The research content of this article is of great significance for the effective development of volcanic gas reservoirs in eruptive facies.