METHOD FOR RECOGNIZING THIEF ZONE IN OIL POOL, COMPUTER APPARATUS AND COMPUTER READABLE STORAGE MEDIUM

A method for recognizing a thief zone in an oil pool, a computer apparatus and a computer readable storage medium, wherein, the method comprises: calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, the relative contribution coefficient being a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval; determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools; calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to the magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

Skip to: Description  ·  Claims  · Patent History  ·  Patent History
Description
TECHNICAL FIELD

The present invention relates to the technical field of carbonatite oil pool exploitation, in particular to a method for recognizing a thief zone in an oil pool, a computer apparatus, and a computer readable storage medium.

BACKGROUND

A thief zone refers to a thin reservoir stratum which has a permeability much higher than the average permeability of the reservoir stratums, fluids mainly flow along the thief zone, causing the water breakthrough to be too fast, which greatly reduces the swept volume, results in invalid circulation of water injection and affects the overall development effect of the oil field. At present, the thief zone is generally recognized and represented by means of geological static data, yield, liquid production index, production increase contribution rate, single-layer liquid production index, dimensionless pressure coefficient, etc. However, these dynamic and static recognition methods all have certain limitations. The thief zone cannot be recognized quantitatively based on the geological static data; when the thief zone is recognized based on yield data, the concept of production pressure differential is not taken into consideration; when the thief zone is divided according to the indexes such as the liquid production index, the production increase contribution rate, the single-layer liquid production index and the dimensionless pressure coefficient, the limitation conditions such as reservoir thickness or extremely poor permeability are not taken into consideration. Up to now, there is still not a method that can recognize the thief zone fast and accurately.

SUMMARY

The embodiments of the present invention provide a method for recognizing a thief zone in an oil pool in order to solve the technical problem that the thief zone recognition has a low accuracy in the prior art. The method comprises: calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval; determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools; calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

The embodiments of the present invention also provide a computer apparatus in order to solve the technical problem that the thief zone recognition has a low accuracy in the prior art. The computer apparatus comprises: a processor; and a memory comprising computer readable instructions. The processor is enabled to execute the following operations when the computer readable instructions are executed: calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval; determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools; calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

The embodiments of the present invention also provide a computer readable storage medium comprising computer readable instructions in order to solve the technical problem that the thief zone recognition has a low accuracy in the prior art. The computer readable instructions enable the processor to at least execute the following operations when the computer readable instructions are executed: calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval; determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools; calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

In the embodiments of the present invention, the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging are calculated (for example, the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging can be calculated based on dynamic monitoring data of the oil pool production logging), the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient are determined according to the characteristics of different oil pools, and at last, whether or not a thief zone is developed for each reservoir stratum of each well can be determined fast according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient. Since the calculation of the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient has fully considered the influence of thickness on yield contribution, the thief zone recognition is allowed to be more in line with actual situations, thus helping improving the accuracy of the thief zone recognition.

BRIEF DESCRIPTION OF THE DRAWINGS

To explain the technical solutions in the embodiments of the present invention more clearly, the following will briefly introduce the figures needed in the description of the embodiments. Obviously, the figures in the following description are only some embodiments of the present invention, and for ordinary skilled persons in the art, other figures may also be obtained based on these figures without paying any creative efforts. In the figures:

FIG. 1 is a flow chart of a method for recognizing a thief zone in an oil pool in the embodiments of the present invention;

FIG. 2 is a discrimination graph of the thief zone recognition in the embodiments of the present invention;

FIG. 3 is a schematic diagram of the thief zone recognition in a carbonatite oil pool in the embodiments of the present invention;

FIG. 4 is a block diagram of the structure of a computer apparatus in the embodiments of the present invention.

 DETAILED DESCRIPTION OF THE INVENTION

In order to make the object, the technical solutions and the advantages of the present invention more clear, the following will provide a further detailed description of the embodiments of the present invention in combination with the figures. Here, the exemplary embodiments of the present invention and the description thereof are intended for explaining the present invention, not for limiting the present invention.

FIG. 1 is a flow chart of a method for recognizing a thief zone in an oil pool in the embodiments of the present invention. As shown in FIG. 1, the method for recognizing a thief zone in an oil pool in the embodiments of the present invention can comprise:

Step 101: calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval;

Step 102: determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools;

Step 103: calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured;

Step 104: determining whether or not a thief zone is developed for each reservoir stratum of each well, according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

As can be seen from FIG. 1, in the embodiments of the present invention, whether or not a thief zone is developed for each reservoir stratum of each well can be determined fast by: calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging (for example, the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging can be calculated based on dynamic monitoring data of the oil pool production logging), and determining the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient according to the characteristics of different oil pools, and at last, whether or not a thief zone is developed for each reservoir stratum of each well can be determined fast according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient. Since the calculation of the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient has fully considered the influence of thickness on yield contribution, the thief zone recognition is allowed to be more in line with actual situations, thus helping improving the accuracy of the thief zone recognition.

In a concrete implementation, it is possible to obtain all the single-well single-layer (i.e., single-reservoir stratum) thicknesses and the corresponding single-layer yields based on monitoring data on the production logging on site, and thereby obtain a single-layer thickness percentage and a single-layer yield percentage, and at last calculate the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient (RCI) by using the single-well single-layer yield, the single-layer thickness, the single-layer thickness percentage and the single-layer yield percentage.

In a concrete implementation, it is assumed that the reservoir stratum interval has n single layers, the yield of the ith layer is Qi, the thickness of the ith layer is hi, the total yield of the reservoir stratums is Qt, and the total thickness of the reservoir stratums is ht. The abscissa in the thief zone recognition graph (i.e., the yield contribution value per unit thickness for single-reservoir stratum) is a ratio of the single-layer yield to the single-layer thickness, i.e., the yield contribution value per unit thickness for single-reservoir stratum, this parameter can effectively solve the problem that the thickness of the thief zone is not considered in the previous methods for recognizing a thief zone.

In a concrete implementation, in order to recognize the thief zone more quickly, in this embodiment, the step of determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient comprises: drawing a graph by taking the yield contribution value per unit thickness for single-reservoir stratum of individual reservoir stratum in the oil pool production logging as an ordinate and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging as an abscissa, wherein, an intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas; and determining whether or not a thief zone is developed for each reservoir stratum of each well according to the distribution positions of the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the relative contribution coefficient of each reservoir stratum of each well in different areas of the graph.

To be specific, as shown in FIG. 2, after the graph has been drawn with the yield contribution value per unit thickness for single-reservoir stratum of individual reservoir stratum in the oil pool production logging as the ordinate and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging as the abscissa, the intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas, i.e., the intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas according to the magnitude relationships of the coordinate values with the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient. The areas are, for example, a thief zone-developed area, a thief zone-undeveloped area and an area that is not considered due to excessively low yield per unit thickness. Whether or not a thief zone is developed can be determined quickly according to the distribution positions of the data of each reservoir stratum of each well in the different areas.

In a concrete implementation, the step of determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient comprises: not judging the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is smaller than the smallest yield contribution value per unit thickness for single-reservoir stratum; determining the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is smaller than the smallest relative contribution coefficient to be a non-thief zone; and determining the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is greater than the smallest relative contribution coefficient to be a thief zone.

In a concrete implementation, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient can be determined with respect to different oil pools. The single layer of which the yield contribution value per unit thickness for single-reservoir stratum is too low is not sufficient to influence the water-flooding development of the oil pool, and does not have a value for thief zone recognition. Thus, there is a need of determining the smallest yield contribution value per unit thickness for single-reservoir stratum. Due to the differences in the factors such as the physical properties of the oil pool, the smallest yield contribution values per unit thickness for single-reservoir stratum of different oil pools should be different, and generally can be a half of the average value of the yield contribution values per unit thickness for single-reservoir stratum. For example, for a carbonatite oil pool, the smallest yield contribution value per unit thickness for single-reservoir stratum can be 50 stb/ft. The higher the smallest relative contribution coefficient is, the greater the productivity of the single layer is. The contribution of the productivity of the thief zone is greater than that of the overall productivity of the reservoir stratums. In general, the relative contribution coefficient for thief zone judging is defined to a value greater than or equal to 2. For example, for a carbonatite oil pool, the smallest relative contribution coefficient is 2.

The following will give a description of the above method for recognizing a thief zone in an oil pool in combination with concrete examples. The carbonatite oil pool is taken as an example.

(1) Data Collection and Data Quality Control

The method is used to recognize the position of the thief zone, the collected data is the production logging data of the carbonatite oil pool, specifically including all the single-layer thicknesses and the corresponding single-layer yields. The recognition process can be initiated after all the data has been collected and the quality control thereof has been conducted.

This embodiment is based on the result of preliminary screening, the data of 110 single layers of 25 wells is obtained, and the yield contribution values per unit thickness for single-reservoir stratum and relative contribution coefficients (RCI) are calculated using the single-layer yield, the single-layer thickness, the single-layer thickness percentage and the single-layer yield percentage. The result is shown in Table 1.

TABLE 1 Data of a group of candidate wells for carbonatite thief zone recognition Single-layer Single-layer Single-layer yield contribution relative Well Single-layer thickness Single-layer yield value per unit contribution number thickness (m) percentage (%) yield (stb) percentage (%) thickness (stb/m) coefficient W1 4.00 15.38 328.00 18.93 82.00 1.23 W1 7.00 26.92 35.60 2.05 5.09 0.08 W1 4.00 15.38 98.90 5.71 24.73 0.37 W1 4.00 15.38 440.00 25.40 110.00 1.65 W1 7.00 26.92 830.00 47.91 118.57 1.78 W2 6.00 27.27 175.00 12.08 29.17 0.44 W2 4.00 18.18 152.00 10.49 38.00 0.58 W2 4.00 18.18 19.00 1.31 4.75 0.07 W2 3.00 13.64 362.00 24.98 120.67 1.83 W2 5.00 22.73 741.00 51.14 148.20 2.25 W3 1.00 4.55 206.00 19.32 206.00 4.25 W3 2.00 9.09 450.00 42.21 225.00 4.64 W3 5.00 22.73 51.00 4.79 10.20 0.21 W3 4.00 18.18 116.00 10.88 29.00 0.60 W3 4.00 18.18 0.00 0.00 0.00 0.00 W3 3.00 13.64 142.00 13.32 47.33 0.98 W3 3.00 13.64 101.00 9.48 33.67 0.70 W4 4.27 26.42 68.30 10.20 16.00 0.39 W4 3.96 24.50 68.00 10.10 17.17 0.41 W4 3.35 20.73 200.00 29.80 59.70 1.44 W4 3.05 18.87 0.00 0.00 0.00 0.00 W4 1.53 9.47 334.00 49.80 218.30 5.26 W5 11.00 36.67 0.00 0.00 0.00 0.00 W5 5.00 16.67 0.00 0.00 0.00 0.00 W5 6.00 20.00 410.00 32.80 68.33 1.64 W5 8.00 26.67 840.00 67.20 105.00 2.52 W6 4.50 13.04 5.00 0.60 1.11 0.05 W6 30.00 86.96 835.00 99.64 27.83 1.15 W7 2.50 27.78 480.00 30.38 192.00 1.09 W7 1.50 16.67 640.00 40.51 426.67 2.43 W7 5.00 55.56 460.00 29.11 92.00 0.52 W8 21.00 57.53 1016.00 34.75 48.38 0.60 W8 5.50 15.07 46.00 1.57 8.36 0.10 W8 10.00 27.40 1862.00 63.68 186.20 2.32 W9 6.25 17.11 242.00 5.70 38.72 0.33 W9 8.08 22.12 994.00 23.30 123.02 1.05 W9 3.81 10.43 258.00 6.00 67.72 0.58 W9 2.89 7.91 0.00 0.00 0.00 0.00 W9 1.83 5.01 0.00 0.00 0.00 0.00 W9 3.66 10.02 0.00 0.00 0.00 0.00 W9 3.50 9.58 1089.00 25.50 311.14 2.66 W9 3.81 10.43 62.90 1.50 16.51 0.14 W9 2.69 7.37 1625.00 38.00 604.09 5.16 W10 3.20 31.16 283.28 10.09 88.52 0.32 W10 2.09 20.35 838.62 29.88 401.25 1.47 W10 4.98 48.49 1684.50 60.02 338.25 1.24 W11 9.00 14.52 1300.00 34.99 144.44 2.41 W11 23.00 37.10 1450.00 39.03 63.04 1.05 W11 30.00 48.39 965.00 25.98 32.17 0.54 W12 8.08 11.86 714.00 15.40 88.37 1.30 W12 3.50 5.14 0.00 0.00 0.00 0.00 W12 7.77 11.41 459.00 9.90 59.07 0.87 W12 17.07 25.06 1998.00 43.00 117.05 1.72 W12 26.06 38.26 1214.00 26.10 46.58 0.68 W12 5.64 8.28 265.00 5.70 46.99 0.69 W13 10.00 36.63 913.00 23.99 91.30 0.66 W13 8.10 29.67 2316.00 60.87 285.93 2.05 W13 5.10 18.68 289.00 7.60 56.67 0.41 W13 4.10 15.02 185.00 4.86 45.12 0.32 W14 8.00 22.22 660.00 13.27 82.50 0.60 W14 21.00 58.33 3180.00 63.92 151.43 1.10 W14 7.00 19.44 1135.00 22.81 162.14 1.17 W15 2.00 16.95 60.08 7.08 30.04 0.42 W15 2.80 23.73 230.37 27.15 82.27 1.14 W15 3.00 25.42 50.72 5.98 16.91 0.24 W15 4.00 33.90 507.40 59.79 126.85 1.76 W16 2.50 21.74 934.00 61.21 373.60 2.82 W16 6.00 52.17 592.00 38.79 98.67 0.74 W16 3.00 26.09 0.00 0.00 0.00 0.00 W17 8.00 15.38 136.00 3.40 17.00 0.22 W17 9.00 17.31 22.00 0.50 2.44 0.03 W17 15.00 28.85 1575.00 39.30 105.00 1.36 W17 10.00 19.23 1037.00 25.90 103.70 1.35 W17 10.00 19.23 1236.00 30.90 123.60 1.61 W18 6.20 51.67 1786.60 56.99 288.16 1.10 W18 5.80 48.33 1348.30 43.01 232.47 0.89 W19 3.97 42.69 1537.00 79.00 387.15 1.85 W19 1.22 13.12 336.00 17.00 275.41 1.30 W19 4.11 44.19 73.60 4.00 17.91 0.09 W20 6.00 12.00 547.00 13.90 91.17 1.16 W20 17.00 34.00 1270.00 32.30 74.71 0.95 W20 21.00 42.00 1680.00 42.80 80.00 1.02 W20 6.00 12.00 430.00 10.90 71.67 0.91 W21 7.00 21.21 1396.00 90.80 199.43 4.28 W21 6.00 18.18 0.00 0.00 0.00 0.00 W21 20.00 60.61 141.00 9.20 7.05 0.15 W22 5.25 18.68 139.00 5.36 26.48 0.29 W22 3.75 13.34 211.00 8.14 56.27 0.61 W22 10.76 38.28 628.00 24.23 58.36 0.63 W22 3.02 10.74 745.00 28.74 246.69 2.68 W22 5.33 18.96 869.00 33.53 163.04 1.77 W23 7.00 12.87 540.00 20.29 77.14 1.58 W23 18.00 33.09 111.16 4.11 6.18 0.12 W23 12.00 22.06 733.47 27.56 61.12 1.25 W23 6.00 11.03 74.14 2.74 12.36 0.25 W23 8.40 15.44 274.62 10.32 32.69 0.67 W23 3.00 5.51 929.02 34.98 309.67 6.34 W24 7.00 12.73 502.00 17.35 71.71 1.36 W24 18.00 32.73 55.80 1.93 3.10 0.06 W24 12.00 21.82 806.00 27.86 67.17 1.28 W24 6.00 10.91 254.00 8.78 42.33 0.80 W24 12.00 21.82 1275.00 44.07 106.25 2.02 W25 1.99 6.07 5.72 0.27 2.87 0.04 W25 1.83 5.58 79.40 3.72 43.39 0.67 W25 4.88 14.89 349.00 16.35 71.52 1.10 W25 3.20 9.76 0.00 0.00 0.00 0.00 W25 1.98 6.04 253.00 11.86 127.78 1.96 W25 8.99 27.43 249.00 11.67 27.70 0.43 W25 6.86 20.93 743.00 34.82 108.31 1.66 W25 3.05 9.30 455.00 21.32 149.18 2.29

(2) Determination of the Yield Contribution Values Per Unit Thickness for Single-Reservoir Stratum

The single layer of which the yield contribution value per unit thickness for single-reservoir stratum is too low is not sufficient to influence the water-flooding development of the oil pool, and does not have a value for thief zone recognition, thus, there is a need of determining a smallest yield contribution value per unit thickness for single-reservoir stratum. Due to the differences in the factors such as the physical properties of the oil pool, the smallest yield contribution values per unit thickness for single-reservoir stratum of different oil pools should be different, and generally can be a half of the average value of the yield contribution values per unit thickness for single-reservoir stratum. The average value of the yield contribution values per unit thickness for single-reservoir stratum in this embodiment is 98.53 stb/ft, and the smallest yield contribution value per unit thickness for single-reservoir stratum can be 50 stb/ft.

(3) Determination of the Relative Contribution Coefficient for the Thief Zone Judging

The relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to the total yield per unit thickness, the larger value for the ratio is, the greater the productivity of the single layer is. The contribution of the productivity of the thief zone is greater than that of the overall productivity of the reservoir stratums. In general, the relative contribution coefficient for thief zone judging is greater than or equal to 2, and is 2 in this example.

(4) Drawing a Discrimination Graph of the Relative Contribution Coefficient and the Yield Contribution Value Per Unit Thickness for Single-Reservoir Stratum.

The discrimination graph is drawn by taking the yield contribution value per unit thickness for single-reservoir stratum as the abscissa, and the relative contribution coefficient as the ordinate. According to the judging conditions applicable for different oil pools, the discrimination graph of the relative contribution rates and the per unit yield contributions is divided into three areas. The smallest yield contribution value per unit thickness for single-reservoir stratum in this embodiment is 50 stb/ft, the relative contribution coefficient for thief zone judging is 2, and the three discrimination areas (i.e., the area that is not considered, the thief zone-developed area and the thief zone-undeveloped area) are as shown in FIGS. 2 and 3.

(5) Performance of Thief Zone Recognition Based on the Discrimination Graph

The recognition result is shown in FIG. 3, in which the area that is not considered, the thief zone-developed area and the thief zone-undeveloped area are represented by means of dotted lines.

1. According to the discrimination graph of the relative contribution rates and the yield contribution values per unit thickness for single-reservoir stratum, in the data in this embodiment, data points (the data points include: yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients) of 72 single layers are located on the left of the graph (i.e., in the area that is not considered), in other words, the abscissa values thereof are smaller than the smallest yield contribution value per unit thickness for single-reservoir stratum. It indicates that the per unit yield contributions of this layer are not sufficient to cause influences to the water-flooding development of the oil pool, and thus are not considered.

2. Data points of 21 single layers are located on the lower right side of the discrimination graph (i.e., in the thief zone-undeveloped area). The per unit yield contributions of these single layers have reached the level that can influence the water-flooding development of the oil pool, but the relative contribution coefficients are relative low, and thus these layers are recognized to be non-thief zones.

3. Data points of 17 single layers are distributed on the upper right side of the discrimination graph (i.e., in the thief zone-developed area). It indicates that the per unit yield contribution values thereof have reached the level that can influence the water-flooding development of the oil pool, and the relative contribution coefficients are higher than that of the ordinary reservoir stratums, and thus these layers are recognized to be thief zones.

The embodiments of the present invention also provide a computer readable storage medium comprising computer readable instructions, and the computer readable instructions enable the processor to at least execute the following operations when the computer readable instructions are executed: calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratums in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval; determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools; calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; determining whether or not a thief zone is developed for each reservoir stratum of each well, according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

In one embodiment, the above computer readable instructions enable the processor to: draw a graph by taking the yield contribution value per unit thickness for single-reservoir stratum of individual reservoir stratum in the oil pool production logging as an ordinate and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging as an abscissa, wherein, an intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas; and determine whether or not a thief zone is developed for each reservoir stratum of each well according to the distribution positions of the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the relative contribution coefficient of each reservoir stratum of each well in different areas of the graph.

In one embodiment, the above computer readable instruction enable the processor: not to judge the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is smaller than the smallest yield contribution value per unit thickness for single-reservoir stratum; to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is smaller than the smallest relative contribution coefficient to be a non-thief zone; and to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is greater than the smallest relative contribution coefficient to be a thief zone.

In a concrete implementation, the above computer readable storage medium can comprise a physical device for storage of information, which can digitize the information and store the information with an electrical, a magnetic, or an optical medium. The computer readable storage medium in this embodiment can comprise: a device that uses electrical energy to store information, which can be various types of memories such as a RAM, a ROM, etc.; a device that uses magnetic energy to store information, which can be a hard disc, a floppy disk, a magnetic tape, a magnetic core memory, a magnetic bubble memory, a usb flash disk, etc.; and a device that stores information through optical means, which can be a CD, a DVD, etc. Of course, there are other types of readable storage media, such as a quantum memory, a graphene memory, etc.

The embodiments of the present invention also provide a computer apparatus, as shown in FIG. 4, the computer apparatus comprises: a processor 401; and a memory 402 comprising computer readable instructions, the memory 402 coupled to the processor 401. The computer readable instructions enable the processor to at least execute the following operations when the computer readable instructions are executed: calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in the oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval; determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient, from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools; calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; determining whether or not a thief zone is developed for each reservoir stratum of each well, according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

In one embodiment, the above computer readable instructions enable the processor: to draw a graph by taking the yield contribution value per unit thickness for single-reservoir stratum of individual reservoir stratum in the oil pool production logging as an ordinate and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging as an abscissa, wherein, an intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas; and to determine whether or not a thief zone is developed for each reservoir stratum of each well, according to the distribution positions of the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the relative contribution coefficient of each reservoir stratum of each well in different areas of the graph.

In one embodiment, the above computer readable instructions enable the processor: not to judge the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is smaller than the smallest yield contribution value per unit thickness for single-reservoir stratum; to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is smaller than the smallest relative contribution coefficient to be a non-thief zone; and to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is greater than the smallest relative contribution coefficient to be a thief zone.

In the embodiments of the present invention, whether or not a thief zone is developed for each reservoir stratum of each well can be determined quickly by: calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of individual reservoir stratums in the oil pool production logging (for example, the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging can be calculated based on dynamic monitoring data on the oil pool production logging), determining the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient according to the characteristics of different oil pools, and at last, whether or not a thief zone is developed for each reservoir stratum of each well can be determined fast according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient. Since the calculation of the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient has fully considered the influence of thickness on yield contribution, the thief zone recognition is allowed to be more in line with actual situations, thus helping improving the accuracy of the thief zone recognition.

The persons skilled in the art shall understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can be implemented in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment that combines software and hardware. In addition, the present invention can be implemented in the form of a computer program product which is implemented on a computer applicable storage medium (including but not limited to a disk memory, a CD-ROM, an optical memory, etc.) that includes computer applicable program codes.

The present invention is described with reference to the flow chart and/or block diagram of the method, apparatus (system) and computer program product according to the embodiments of the present invention. It should be understood that each procedure and/or box in the flow chart and/or block diagram and a combination of the procedures and/or boxes in the flow chart and/or block diagram can be realized by means of the computer program instructions. The computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor or a processor of other programmable data processing apparatuses to produce a machine, so that the instructions executed by the computer or the processor of other programmable data processing apparatuses generate a device used for realizing the functions specified in one or more procedures in the flow chart and/or one or more boxes in the block diagram.

These computer program instructions can also be stored in a computer readable memory that can guide the computer or other programmable data processing apparatuses to work in a specific way, so that the instructions stored in the computer readable memory generate a manufacture including an instruction device, which instruction device realizes the functions specified in one or more procedures in the flow chart and/or one or more boxes in the block diagram.

These computer program instruction can also be loaded on a computer or other programmable data processing apparatuses, so that a series of operation steps are executed on the computer or other programmable apparatuses to generate the processing realized by the computer, and thus, the instructions executed on the computer or other programmable apparatuses provide steps for realizing the functions specified in one or more procedures in the flow chart and/or one or more boxes in the block diagram.

The above mentioned specific embodiments further explain the object, the technical solutions and the advantageous effects of the present invention. It should be understood that the above content is merely the specific embodiments of the present invention, and is not used to limit the protection scope of the present invention. Any amendments, equivalent substitutions and improvements within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for recognizing a thief zone in an oil pool, comprising:

calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval;
determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools;
calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; and
determining whether or not a thief zone is developed for each reservoir stratum of each well, according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

2. The method for recognizing a thief zone in an oil pool according to claim 1, wherein determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient comprises:

drawing a graph by taking the yield contribution value per unit thickness for single-reservoir stratum of individual reservoir stratum in the oil pool production logging as an ordinate and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging as an abscissa, wherein, an intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas; and
determining whether or not a thief zone is developed for each reservoir stratum of each well, according to distribution positions of the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the relative contribution coefficient of each reservoir stratum of each well in the different areas of the graph.

3. The method for recognizing a thief zone in an oil pool according to claim 1, wherein determining whether or not a thief zone is developed for each reservoir stratum of each well according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient comprises:

not judging the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is smaller than the smallest yield contribution value per unit thickness for single-reservoir stratum; determining the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is smaller than the smallest relative contribution coefficient to be a non-thief zone; and
determining the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is greater than the smallest relative contribution coefficient to be a thief zone.

4. The method for recognizing a thief zone in an oil pool according to claim 1, wherein for a carbonatite oil pool, the smallest yield contribution value per unit thickness for single-reservoir stratum is 50, and the smallest relative contribution coefficient is 2.

5. A computer apparatus comprising a processor and a memory comprising computer readable instructions, the processor being enabled to execute the following operations when the computer readable instructions are executed:

calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and the relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval;
determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient, from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools;
calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to-be-measured; and
determining whether or not a thief zone is developed for each reservoir stratum of each well, according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

6. The computer apparatus according to claim 5, wherein the computer readable instructions enable the processor to:

draw a graph by taking the yield contribution value per unit thickness for single-reservoir stratum of individual reservoir stratum in the oil pool production logging as an ordinate and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging as an abscissa, wherein, an intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas; and
determine whether or not a thief zone is developed for each reservoir stratum of each well, according to the distribution positions of the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the relative contribution coefficient of each reservoir stratum of each well in the different areas of the graph.

7. The computer apparatus according to claim 5, wherein the computer readable instructions enable the processor:

not to judge the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is smaller than the smallest yield contribution value per unit thickness for single-reservoir stratum;
to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is smaller than the smallest relative contribution coefficient to be a non-thief zone; and
to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is greater than the smallest relative contribution coefficient to be a thief zone.

8. A computer readable storage medium comprising computer readable instructions, wherein the computer readable instructions enable a processor to at least execute the following operations when the computer readable instructions are executed:

calculating a yield contribution value per unit thickness for single-reservoir stratum and a relative contribution coefficient of individual reservoir stratum in oil pool production logging, wherein, the yield contribution value per unit thickness for single-reservoir stratum is a ratio of a single-reservoir stratum yield to a single-reservoir stratum thickness, and relative contribution coefficient is a ratio of the yield contribution value per unit thickness for single-reservoir stratum to a yield per unit thickness for the whole reservoir stratum interval;
determining a smallest yield contribution value per unit thickness for single-reservoir stratum and a smallest relative contribution coefficient, from the yield contribution values per unit thickness for single-reservoir stratum and the relative contribution coefficients in the oil pool production logging, according to the characteristics of different oil pools, wherein, the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient meet the requirements of thief zone recognition for different oil pools;
calculating the yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient of each reservoir stratum of each well in the oil pool to be measured; and
determining whether or not a thief zone is developed for each reservoir stratum of each well, according to a magnitude relationship between the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the smallest yield contribution value per unit thickness for single-reservoir stratum and according to a magnitude relationship between the relative contribution coefficient of each reservoir stratum of each well and the smallest relative contribution coefficient.

9. The computer readable storage medium comprising computer readable instructions according to claim 8, wherein the computer readable instructions enable the processor to:

draw a graph by taking the yield contribution value per unit thickness for single-reservoir stratum of individual reservoir stratum in the oil pool production logging as an ordinate and the relative contribution coefficient of individual reservoir stratum in the oil pool production logging as an abscissa, wherein, an intersection line of the smallest yield contribution value per unit thickness for single-reservoir stratum and the smallest relative contribution coefficient divides the graph into different areas; and
determine whether or not a thief zone is developed for each reservoir stratum of each well, according to the distribution positions of the yield contribution value per unit thickness for single-reservoir stratum of each reservoir stratum of each well and the relative contribution coefficient of each reservoir stratum of each well in the different areas of the graph.

10. The computer readable storage medium comprising computer readable instructions according to claim 8, wherein the computer readable instructions enable the processor:

not to judge the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is smaller than the smallest yield contribution value per unit thickness for single-reservoir stratum; to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is smaller than the smallest relative contribution coefficient to be a non-thief zone; and
to determine the reservoir stratum of which the yield contribution value per unit thickness for single-reservoir stratum is greater than the smallest yield contribution value per unit thickness for single-reservoir stratum and the relative contribution coefficient is greater than the smallest relative contribution coefficient to be a thief zone.
Patent History
Publication number: 20190211674
Type: Application
Filed: Jan 25, 2019
Publication Date: Jul 11, 2019
Inventors: Chenji WEI (Beijing), Yong LI (Beijing), Baozhu LI (Beijing), Benbiao SONG (Beijing), Qi ZHANG (Beijing), Lihui XIONG (Beijing), Jie ZHENG (Beijing), Weimin ZHANG (Beijing), Jing ZHANG (Beijing), Qi WANG (Beijing)
Application Number: 16/257,718
Classifications
International Classification: E21B 49/00 (20060101);