Investigation into Hydraulic Fracture Propagation Behavior during Temporary Plugging and Diverting Fracturing in Coal Seam

Summary: The multi-fracture growth behavior of thin interbedded tight sandstone in the Ordos basin was investigated through a multi-cluster fracturing experiment. The results showed that the mechanical parameters difference between sandstone and mudstone is significant. When the stress difference between layers is less than 3 MPa, the mudstone layer does not restrain the vertical growth of hydraulic fractures, and the opening of laminas or interfaces is the main mechanism causing height containment. However, when the stress difference is equal to or greater than 3 MPa and the mudstone thickness is more than 0.4, the hydraulic fracture height tends to be restrained. Increasing fluid viscosity or pumping rate can reduce filtration and facilitate hydraulic fractures penetrating through the laminas or interfaces and propagating into adjacent layers.