In Algeria, seven wells (including one injector) were stimulated with high conductivity TSO designs. Post-frac oil production yielded a 6-fold increase, while post-frac watercuts were approximately 0.1%, verifying that the TSO designs succeeded in arresting fracture height growth.
In March of 1999 a series of six hydraulic fracturing treatments were performed in an area of Algeria known as TFT (see Figure 1). Seven wells (6 producers and 1 injector) were to be fracture stimulated with risk of propagating into lower mobile water zone. A series of treatment design steps were carried out for each well that helped prevent excessive height growth while fracturing and ultimately limited water production after the treatments. The methodology incorporated utilizes both two-dimentional and pseudo three-dimentional fracture modeling in order to estimate different scenarios of fracture height growth. This method resulted in a better estimation of fluid volumes and pump rates that would limit height growth, yet optimize proppant placement and fracture conductivity in the productive part of the interval. The resulting net increase in oil production from the six producer wells was over 29.93 m3/hr. This paper explains the design methodology used during the campaign and presents representative case histories.
Author(s): John N. Engels, Kevin W. England, Schlumberger
Paper Number: SPE 67230