Definition - What does Breaking Down mean?
Breaking Down or simply breakdown refers to the breakdown pressure at which the formation rock will break and allow fluids to flow inside. Breakdown pressure value is used to calculate the minimum principal stress and maximum horizontal stress of formation rocks. It is also used to access the formation treatment operations. Breaking down is also referred to as Formation break down pressure or fracture initiation pressure.
Petropedia explains Breaking Down
Breaking down mainly depends on the compressive stress associated with the formation rock and the strength of the formation itself. When the applied pressure exceeds both the compressive stress and formation strength the formation will break. By maintaining the pressure above the breakdown pressure value, the formation rock fractures and these fractures propagate in a perpendicular direction to the least principal stress.
Operations like matrix stimulation, surging and leak off test are conducted below the breakdown pressure while hydraulic fracturing jobs are conducted above the breakdown pressure value. The breakdown pressure depends on the formation type, size, fracture fluid and well deviation angle.The plot below indicates that the pressure increases linearly with the volume pumped and at a certain stage the pressure decreases indicating that the formation has started to break down. Formation Breakdown Pressure value is reached when the pressure no longer increases even with an increase in volume pumped.