METHOD FOR DETERMINING CURRENT FORMATION PRESSURE IN AN OPERATING WELL OF A TOURNAISIAN-FAMENNIAN DEPOSIT WITHOUT ITS STOPPING Russian patent published in 2020 - IPC E21B47/06 E21B49/00 G06F30/20 

FIELD: measurement technology; oil and gas industry.

SUBSTANCE: invention relates to methods of determining current formation pressure without stopping wells for investigation during their operation. Method consists in determining the oil saturated formation parameters: the cumulative water production (Qwⁿ), initial reservoir pressure (Prsⁿ) in the selection zone of the well, operating time (T) after input from drilling, bottomhole pressure (Pbh), skin factor (S), gas factor (Gf), initial permeability of collector (Kperⁿ) in the sampling zone of this well, oil flow rate (Qn), further, by the values of Prsⁿ and T, the well bed formation pressure Prs^T-M of the model is established by mathematical relationship. Using the previously defined parameters Prsⁿ, T, Qwⁿ, Pbh, S, Gf, Kperⁿ and Qn by discriminant analysis calculated discriminant function value Z hole pattern on the mathematical formula. Class of well model is determined from discriminant function Z: at Z>0 – model of well is referred to the first class, at Z<0 – well model is referred to the second class. If the constructed model of the well relates to the first class, formation pressure of the model of the well Prs^T-M1 is calculated using a mathematical formula. In the case of classification well model to the second class is calculated pressure reservoir well model Prs^T-M2 on the mathematical formula. Using the previously obtained values of Prs^T-M and Prs^T-M1 or Prs^T-M2, current reservoir pressure of the exploited well is calculated using a mathematical formula.

EFFECT: improving accuracy of determining current formation pressure at operated well without its stopping.

1 cl, 1 dwg