1973 Third Symposium on Numerical Simulation of Reservoir Performance Houston, Texas January 11–12, 1973
Most research on water coning has been directed toward minimizing water production by reduced well penetration or production rate control. However, complete depletion of an oil column underlain by water will necessarily be accompanies by considerable water production, at least in the latter stages of depletion. By means of numerical simulation a systematic study was made of the effects of reservoir and well parameters on water coning performance. Included were the effects of aquifer thickness, well penetration, pressure drawdown, and horizontal to vertical permeability ratio. permeability ratio. These studies revealed that higher water-oil ratios, at every stage of depletion, resulted from increasing well penetration or increasing pressure drawdown at the producing well. Accompanying the increase in pressure drawdown at the producing well. Accompanying the increase in water-oil ratio is an increase in oil production rate of the same magnitude thus decreasing the operating life of the well. There is no indication that the ultimate oil recovery is adversely affected by increased production rates. As a matter of fact it appears that high production production rates. As a matter of fact it appears that high production rates could lead to improved economic oil recovery. Produced water-oil ratio at every stage of depletion is strongly influenced by the ratio of horizontal to vertical permeability and to a lesser degree by aquifer thickness.
Water coning, during which bottom water gradually or abruptly breaks into an oil- or gas-producing well, has long been a problem in oil fields. It is a very complex problem and has been investigated by many researchers.