Pulsed fluid migration from over pressured compartments : modeling studies

Abstract EN

Overpressure in a sealed compartment can puncture the seal bounding it when the fracture pressure is exceeded.

After the pressure is released, the seal may heal and, if the over pressurizing mechanism continues to operate, pressure may build up again, andfracture the seal again.

In this way, a repetitive cycle may be established.

A mathematical model is set forth and solved numerically.

Controls on existence, oscillation period, amplitude and waveform are delineated.

The results suggest that fluid released from compartments at depth into overlying reservoir rock can be episodic, not slow and continuous.

Furthermore, under some conditions there may be a critical depth below which a leaky seal cannot be punctured and hence, after the compartment descends through this depth, the fluids such as the petroleum contained within it will remain trapped.