The Ordovician carbonate reservoir in Taliram Basin is typical of fractured and caved reservoirs with thick oil layer, high temperature, deep zone and extra heterogeneity together with high density, high viscosity and high freezing point et al as common characteristics of crude oil. More than 80% wells have to be stimulated before economically producing. Based on the laboratory researches and plentiful field practices, the following stimulation modes are formed: the multiplayer acid-fracturing for long open-hole interval or layered acid-fracturing, height-control acid-fracturing against bottom water coining, a combination of hydraulic fracturing and acid fracturing. On the basis of drill so&g, logging data, well-recorded data and some geophysical data such as change rate of logging amplitude, cohere body and Jason reversion et al., model for well selecting and layer appraising is developed. We develop high-visco gelling acid, retarded acid based on surfactant, low friction resistance emulsified acid as well as insitu stiffening acid, with better retardancy, low leakage and low friction as the result, with which the damage near the wellbore is effectively solved and deeply penetrated acid-etched fracture is obtained. Furthermore, the 3D acid fracturing optimization design techniques for fractured and caved reservoir brought forward in this paper have accurately calculated the treatment data and fracture geometry, thus the effectiveness of acid fracturing is increased a lot. Up to the end of 2003, more than 220 times of application of acid-fracturing in Ordovician Carbonate Reservoir of Tahe Oilfield located in the northeast of Taliram Basin of China have indicated that 98.8% were effective, with average single-well incremental yield of 60t/d and the period of validity over 250 days, therefore, Tahe oilfield has increased the production about 311.8 × 104t altogether.

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