Abstract:

Unconventional oil (tight oil) is oil trapped in low permeability sandstone, and also is a resource with great potential as it is heavily supplementing oil production from Bach Ho oil field. The tight rock must be stimulated artificially to perform fractures before the production of the oil from the fractured systems. When hydrocarbons are produced, the flow is influenced by the fracture, the stimulated rock, and the matrix rock. The initial decline of a fractured reservoir is faster than the initial decline of a conventional reservoir, and the late time decline of a fractured reservoir is slower than that of a conventional reservoir. Fractured systems have this unconventional flow behavior because of flow regimes, including: fracture linear flow, bilinear flow, formation linear flow, and pseudo-radial flow. In this paper, production behaviors of the Bach Ho Oligocene oil reservoirs are summarized and analyzed. Production rates from a tight oil reservoir are modeled using a cluster serial flow simulator that models the singlephase flow of a slightly-compressible oil. These models can succeed where the analytical models and complex simulations fail by providing estimations for physical parameters, managing uncertainty, and having fast run times.