Oil-water layer evaluation method and device

Abstract

The invention discloses an oil-water layer evaluation method and device. The method comprises the following steps: extracting and calculating to obtain standard start time and standard end time of all group peaks of an analysis sample; extracting standard peak areas of all component peaks of the analysis sample according to the obtained data, and calculating the unit peak area of each component peak; according to different fluid properties, summarizing the unit peak area of each component peak of each analysis sample, and calculating each derived parameter of all analysis samples; establishing an oil-water layer evaluation chart based on derived parameters; calculating the unit peak area of each component peak of the analysis sample in the well to be evaluated, and calculating each derived parameter; and projecting each derived parameter of the to-be-evaluated well to the oil-water layer evaluation chart corresponding to the derived parameter, and determining the formation fluid property of the to-be-evaluated layer of the to-be-evaluated well. According to the method, the oil-water layer evaluation standard is established by utilizing new parameters and oil testing data in the same oil and gas reservoir, and the fluid property of the stratum can be evaluated quickly and accurately.

Description

Technical Field

[0001] The present invention relates to the field of petroleum exploration geochemistry, and particularly to a method and device for evaluating oil and water layers. Background Art

[0002] Due to the relatively wide carbon number range detected by the pyrolysis gas chromatography analysis technology of rocks, and the large number of parameters obtained, it can reflect the changes in the properties of formation fluids from multiple aspects. Especially for the judgment of the degree of secondary transformation of crude oil, the evaluation of water content through the change of peak shape has a more obvious effect.

[0003] Currently, the commonly used evaluation method is to perform relevant calculations on the peak areas of each component peak detected by pyrolysis gas chromatography to obtain a large number of derived parameters for evaluating oil and gas layers.

[0004] However, after the crude oil in many oil and gas reservoirs is damaged, the component peaks are difficult to separate, so the peak areas of each component peak cannot be obtained, and it is difficult to quantitatively evaluate the oil and gas layers. Summary of the Invention

[0005] In view of the above problems, embodiments of the present invention are provided to provide a method and device for evaluating oil and water layers that overcome or at least partially solve the above problems.

[0006] In a first aspect, an embodiment of the present invention provides a method for evaluating oil and water layers, including:

[0007] For an analysis sample with a separation degree greater than a preset threshold within the same oil and gas reservoir as the layer to be evaluated, extract the starting time and ending time of each single peak of all component peaks in the pyrolysis gas chromatography parameters of the analysis sample with a separation degree greater than the preset threshold, and calculate the standard starting time and standard ending time of each component peak;

[0008] For an analysis sample with a separation degree less than or equal to the preset threshold, use the calculated standard starting time and standard ending time of each component peak to extract the standard peak area of all component peaks in the pyrolysis gas chromatography parameters of the analysis sample with a separation degree less than or equal to the preset threshold, and calculate the unit peak area of each component peak of the analysis sample with a separation degree less than or equal to the preset threshold according to the standard peak area;

[0009] According to different fluid properties within the same oil and gas reservoir as the layer to be evaluated, summarize the unit peak areas of each component peak of all analysis samples, and establish unit peak area statistical data corresponding to different fluid properties;

[0010] Calculate various derived parameters of all analysis samples according to the unit peak area statistical data corresponding to different fluid properties;

[0011] Establish an oil and water layer evaluation chart for each derived parameter according to the various derived parameters of all analysis samples;

[0012] For the analysis samples of the layers to be evaluated in the well to be evaluated, calculate the unit peak area of each component peak, and calculate each derived parameter based on the unit peak area of each component peak;

[0013] Using the evaluation charts of oil and water layers corresponding to each derived parameter, project each derived parameter of the well to be evaluated onto the evaluation chart of oil and water layers corresponding to the derived parameter, and determine the formation fluid property of the layer to be evaluated in the well to be evaluated.

[0014] In one embodiment, calculate the standard start time and standard end time of all component peaks, including:

[0015] Using the individual peak start time of all component peaks, calculate the average start time of each component peak in the oil and gas reservoir as the standard start time of the component peak;

[0016] Using the individual peak end time of all component peaks, calculate the average end time of each component peak in the oil and gas reservoir as the standard end time of the component peak.

[0017] In one embodiment, calculate the unit peak area of each component peak according to the standard peak area, including:

[0018] Calculate the unit peak area through the following formula:

[0019]

[0020] Wherein, Si is the unit peak area of nCi, uV·s / mg; G is the sample weight, mg; DnCi is the standard peak area of nCi, uV·s; nCi is the normal alkane with the corresponding carbon number; i is a positive integer.

[0021] In one embodiment, calculate the unit peak area of each component peak according to the standard peak area, including:

[0022] Calculate the unit peak area through the following formula:

[0023]

[0024] Where SPr is the unit peak area of Pr, uV·s / mg; G is the sample weight, mg; DPr is the standard peak area of Pr, uV·s, and Pr is pristane.

[0025] In one embodiment, calculate the unit peak area of each component peak according to the standard peak area, including:

[0026] Calculate the unit peak area through the following formula:

[0027]

[0028] Where SPh is the unit peak area of Ph, uV·s / mg; G is the sample weight, mg; DPh is the standard peak area of Ph, uV·s, and Ph is phytane.

[0029] In one embodiment, it further includes: for the calculation method of the unit peak area of an analysis sample with a resolution greater than a preset threshold, it is to divide the peak area of each component obtained by analyzing with an oil and gas component comprehensive evaluation instrument by the sample weight.

[0030] In one embodiment, calculate derived parameters, including: calculate the total peak area, calculate the retention index, calculate the degradation index, and calculate the water washing index.

[0031] In one embodiment, calculating the total peak area of the sample includes:

[0032] Calculate the total peak area of the sample through the following formula:

[0033]

[0034] Where Sz is the total peak area, uV·s / mg; Si is the unit peak area of nCi, uV·s / mg; SPr is the unit peak area of Pr, uV·s / mg; SPh is the unit peak area of Ph, uV·s / mg.

[0035] In one embodiment, calculating the retention index of the sample includes:

[0036] Calculate the retention index of the sample through the following formula:

[0037]

[0038] Where BL is the retention index, Si is the unit peak area of nCi, uV·s / mg; SPh is the unit peak area of Ph, uV·s / mg.

[0039] In one embodiment, calculating the degradation index of the sample includes:

[0040] Calculate the degradation index of the sample through the following formula:

[0041]

[0042] Where SJ is the degradation index, Si is the unit peak area of nCi, uV·s / mg.

[0043] In one embodiment, calculating the water washing index of the sample includes:

[0044] Calculate the water washing index of the sample through the following formula:

[0045]

[0046] Wherein, SX is the water washing index, Si is the unit peak area of nCi, in uV·s / mg; SPr is the unit peak area of Pr, in uV·s / mg; SPh is the unit peak area of Ph, in uV·s / mg.

[0047] In one embodiment, according to the respective derived parameters of all analysis samples, an oil-water layer evaluation chart corresponding to each derived parameter is established, including:

[0048] According to the different fluid properties to which the analysis samples belong, the derived parameter values of the analysis samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the BL value, and the ordinate of the coordinate system is the Sz value, to establish the retention index evaluation chart of this oil and gas reservoir;

[0049] According to the different fluid properties to which the analysis samples belong, the derived parameter values of the analysis samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the SJ value, and the ordinate of the coordinate system is the Sz value, to establish the degradation index evaluation chart of this oil and gas reservoir;

[0050] According to the different fluid properties to which the analysis samples belong, the derived parameter values of the analysis samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the SX value, and the ordinate of the coordinate system is the Sz value, to establish the water washing index evaluation chart of this oil and gas reservoir.

[0051] In a second aspect, an oil-water layer evaluation device provided by an embodiment of the present invention includes:

[0052] A calculation module, for analysis samples with a separation degree greater than a preset threshold within the same oil and gas reservoir as the layer to be evaluated, extracts the starting time and ending time of each individual peak of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a separation degree greater than the preset threshold, and calculates the standard starting time and standard ending time of each component peak; for analysis samples with a separation degree less than or equal to the preset threshold, uses the calculated standard starting time and standard ending time of each component peak to extract the standard peak area of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a separation degree less than or equal to the preset threshold, and calculates the unit peak area of each component peak according to the standard peak area; summarizes the unit peak areas of each component peak of all analysis samples according to the different fluid properties within the same oil and gas reservoir as the layer to be evaluated, and establishes unit peak area statistical data corresponding to different fluid properties; calculates the respective derived parameters of all analysis samples according to the unit peak area statistical data corresponding to different fluid properties;

[0053] An evaluation chart establishment module, according to the respective derived parameters of all analysis samples, establishes an oil-water layer evaluation chart corresponding to each derived parameter;

[0054] A fluid property determination module calculates the unit peak area of each component peak for the analysis sample of the layer to be evaluated in the well to be evaluated, and calculates various derived parameters based on the unit peak area of each component peak; using the oil-water layer evaluation chart corresponding to each derived parameter, projects the various derived parameters of the well to be evaluated onto the oil-water layer evaluation chart corresponding to the derived parameter to determine the formation fluid property of the layer to be evaluated in the well to be evaluated.

[0055] In one embodiment, the calculation module further includes; for the unit peak area calculation method of the analysis sample with a resolution greater than the preset threshold, it is to divide the peak area of each component obtained by analyzing with an integrated oil and gas component evaluator by the sample weight.

[0056] In a third aspect, an embodiment of the present invention provides a computer storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, an oil-water layer evaluation method is implemented.

[0057] In a fourth aspect, an embodiment of the present invention provides a computing device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, an oil-water layer evaluation method is implemented.

[0058] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:

[0059] An oil-water layer evaluation method and device provided by an embodiment of the present invention. This method calculates the standard start time and standard end time, obtains the standard peak area using the standard start time and standard end time, calculates the unit peak area through the standard peak area, calculates the derived parameters using the unit peak area, establishes an oil-water layer evaluation chart based on the derived parameters, and reflects the fluid property by establishing a new parameter system, providing a new method for evaluating the formation fluid property using the pyrolysis gas chromatography technology, being able to quantitatively evaluate the oil and gas layer, improving the coincidence rate and accuracy of the oil-water layer interpretation, and reducing unnecessary cost waste. Description of the Drawings

[0060] The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0061] Figure 1 is the flowchart of the oil-water layer evaluation method of the present invention;

[0062] Figure 2 is the low-maturity oil evaluation chart established in the embodiment of the present invention;

[0063] Figure 3 is the biodegradable oil evaluation chart established in the embodiment of the present invention;

[0064] Figure 4 is the low-saturation oil layer evaluation chart established in the embodiments of the present invention;

[0065] Figure 5 is the comprehensive chart of Well A in the embodiments of the present invention;

[0066] Figure 6A is the gas chromatogram of Well A at 1490 m in the embodiments of the present invention;

[0067] Figure 6B is the gas chromatogram of Well A at 1490 m after identifying component peaks by the method of the embodiments of the present invention;

[0068] Figure 7 is the evaluation chart of Well A in the embodiments of the present invention;

[0069] Figure 8 is the comprehensive chart of Well B in the embodiments of the present invention;

[0070] Figure 9 is the pyrolysis gas chromatogram of Well B at 2242 m in the embodiments of the present invention;

[0071] Figure 10 is the evaluation chart of Well B in the embodiments of the present invention;

[0072] Figure 11 is the comprehensive chart of Well C in the embodiments of the present invention;

[0073] Figure 12A is the gas chromatogram of Well C at 1719.6 m in the embodiments of the present invention;

[0074] Figure 12B is the gas chromatogram of Well C at 1719.6 m after identifying component peaks by the method of the embodiments of the present invention;

[0075] Figure 13 is the evaluation chart of Well C in the embodiments of the present invention;

[0076] Figure 14 is the schematic structural diagram of the oil-water layer evaluation device provided by the embodiments of the present invention. Detailed implementation manners

[0077] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0078] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", "far", "near", "front", "back" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0079] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0080] The inventors of the present invention have found that after the crude oil in many oil and gas reservoirs is destroyed, the component peaks are difficult to separate, the peak area of ​​each component peak cannot be obtained, and the oil and gas layer cannot be evaluated by the existing evaluation methods.

[0081] In view of the problems existing in the prior art, an embodiment of the present invention provides an oil-water layer evaluation method and device.

[0082] In order to better understand the pyrolysis gas chromatography analysis technology in the present invention, the pyrolysis gas chromatography analysis technology is now explained as follows:

[0083] The application of pyrolysis gas chromatography analysis technology can obtain nC 10 -nC 40 The chromatographic peaks of normal alkanes, pristane and phytane and the relative percentage content of each component are shown in Figure 1. Pristane (Pr) and phytane (Ph) are adjacent to n-heptadecane and n-octadecane, respectively. Pristane (Pr) and phytane (Ph) in isoprenoids are used as the signature peaks to qualitatively identify the names of each component. The parameter directly obtained by the comprehensive evaluation instrument for oil and gas components is nC 10 ~nC 40 The peak height, peak area and mass fraction of the n-alkanes, Pr (phytane) and Ph (pristane) on the left and right. The peak area is automatically extracted by area integration based on the starting time and end time of each peak.

[0084] The following is a detailed description of an oil-water layer evaluation method and device provided by an embodiment of the present invention in conjunction with the accompanying drawings:

[0085] Reference Figure 1 As shown, an oil-water layer evaluation method is provided in an embodiment of the present invention, including:

[0086] S1. For analysis samples with a separation degree greater than a preset threshold within the same oil and gas reservoir as the layer to be evaluated, extract the start time and end time of each individual peak of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a separation degree greater than the preset threshold, and calculate the standard start time and standard end time of each component peak;

[0087] When the separation degree is less than or equal to the preset threshold, the component peaks of the analysis samples cannot be clearly shown in the pyrolysis gas chromatography spectrum. Therefore, in this step, first collect the start time and end time of each individual peak of the analysis samples with a separation degree greater than the preset threshold within the oil and gas reservoir, and calculate the standard start time and standard end time of the component peaks within the oil reservoir;

[0088] For example, in an embodiment of the present invention, extract the start time and end time of each individual peak of all component peaks in the pyrolysis gas chromatography parameters of all analysis samples with a separation degree greater than 1.5 within the oil and gas reservoir. The time points can be directly obtained from the pyrolysis gas chromatography spectrum. Use the average start time of each component peak within the oil and gas reservoir as the standard start time of the component peak, and use the average end time of each component peak within the oil and gas reservoir as the standard end time of the component peak.

[0089] S2. For analysis samples with a separation degree less than or equal to the preset threshold, use the calculated standard start time and standard end time of each component peak to extract the standard peak area of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a separation degree less than or equal to the preset threshold, and calculate the unit peak area of each component peak according to the standard peak area;

[0090] Because the analysis samples with a separation degree less than or equal to the preset threshold cannot obtain the time points through the pyrolysis gas chromatography spectrum, it is necessary to use the calculated standard start time and standard end time as the time of each component peak of the analysis sample, and use the peak area between the standard start time and the standard end time as the standard peak area. The standard peak area of the analysis sample can be automatically extracted by the instrument analysis software. For example, in an embodiment of the present invention, the YQZF-IIIA comprehensive evaluation instrument for oil and gas components produced by Liaoning Haicheng Chemical Instrument Factory and its related software are applied.

[0091] S3. According to different fluid properties within the same oil and gas reservoir as the layer to be evaluated, summarize the unit peak areas of each component peak of each analysis sample, and establish unit peak area statistical data corresponding to different fluid properties;

[0092] According to the previous step, for example, the component peak areas of all analysis samples with a resolution greater than 1.5 in the oil and gas reservoir can be directly obtained by an instrument. The component peak area divided by the sample weight is the unit peak area. Using the standard start time and standard end time, and the standard peak areas of all analysis samples with a resolution less than or equal to 1.5 obtained by the instrument, the standard peak area divided by the sample weight is the unit peak area. According to the analysis samples with known fluid properties in the oil and gas reservoir, they are summarized according to different fluid properties. For example, the unit peak areas of the analysis samples in the oil layer are summarized, and the unit peak areas of the analysis samples in the oil-water coexisting layer are summarized.

[0093] S4. Calculate various derived parameters of all analysis samples according to the unit peak area statistical data corresponding to different fluid properties;

[0094] Among them, the derived parameters are calculated based on the unit peak area of the component peaks to be determined, and the derived parameters may include the total peak area, retention index, degradation index, and water washing index.

[0095] S5. Establish evaluation charts for oil and water layers corresponding to various derived parameters according to the various derived parameters of all analysis samples;

[0096] Among them, referring to Figure 2 as shown, the evaluation chart for the retention index with the retention index as the abscissa and the total peak area as the ordinate is called the evaluation chart for low-maturity oil;

[0097] Since the hydrocarbon substances contained in the source rock of low-maturity oil are not fully mature, the oil-bearing abundance is relatively high, but the components are not complete, and it often shows a relatively high Ph, while the adjacent nC 18 -nC 28 value is relatively low. Therefore, the ratio relationship between the sum of the areas of nC 18 -nC 28 and Ph can be used to judge the maturity of the crude oil. At the same time, Ph is relatively stable and its value will not change much when there is water in the formation. While the adjacent nC 18 -nC 28 value is greatly affected by water. When there is water in the formation, this part of the components will be damaged and the data will decrease. Therefore, the ratio relationship between the sum of the areas of nC 18 -nC 28 and Ph can be used to judge the water content in the formation.

[0098] Referring to Figure 3 as shown, the evaluation chart for the degradation index with the degradation index as the abscissa and the total peak area as the ordinate is called the evaluation chart for biodegraded oil;

[0099] Among them, biodegraded oil is the product of the destruction of normal crude oil, and its characteristic on the gas chromatogram is nC10 -nC 25 is damaged first. The more severely the crude oil is damaged, the lower this part of the peak is, while for nC 28 -nC 31 will bulge after part of it is damaged. Therefore, the ratio of these two parts can be used to judge the degree of damage of the crude oil.

[0100] Reference Figure 4 As shown, the water-washing index evaluation chart with the water-washing index as the abscissa and the total peak area as the ordinate is called the low-saturation oil layer evaluation chart;

[0101] Among them, the characteristics of the low-saturation oil layer are that oil and water are produced together, but its gas logging total hydrocarbon value is high and the peak shape is full, similar to the oil layer. However, it is found that after the crude oil in the formation is affected by water washing, Pr and Ph are often relatively stable, while nC with low carbon numbers 10 -nC 21 is greatly affected by water washing. The degree of loss is proportional to the water content. The heavier the water content, the more the loss. Therefore, by summing the two respectively and establishing a ratio relationship, the water content of the formation can be judged.

[0102] S6. For the analysis samples of the layer to be evaluated in the well to be evaluated, calculate the unit peak area of each component peak, and calculate each derived parameter according to the unit peak area of each component peak;

[0103] For the analysis samples in the well to be evaluated, calculate the unit peak area of each analysis sample by the method of calculating the unit peak area in the above steps, and calculate each derived parameter of the analysis sample according to the unit peak area of each component peak by the method of calculating the derived parameter in the above steps.

[0104] S7. Using the oil-water layer evaluation chart corresponding to each derived parameter, project each derived parameter of the well to be evaluated onto the oil-water layer evaluation chart corresponding to the derived parameter, and determine the formation fluid property of the layer to be evaluated in the well to be evaluated;

[0105] Based on the data obtained from the analysis samples in the well to be evaluated, initially observe the numerical relationship between the component peaks, judge the water content of the formation, determine the oil-water layer evaluation chart, and then project the corresponding derived parameters of the analysis samples onto the corresponding oil-water layer evaluation chart.

[0106] In one embodiment, in the above step S1, the standard starting time and standard ending time of all component peaks are specifically calculated by the following method:

[0107] Using the individual peak starting time of each component peak of the analysis sample with a resolution greater than the preset threshold, calculate the average starting time of each component peak in the oil and gas reservoir as the standard starting time of the component peak;

[0108] Using the end time of each individual peak of all components of the analytical sample with a resolution greater than the preset threshold, the average end time of each component peak in the oil and gas reservoir is calculated as the standard end time of the component peak.

[0109] In one embodiment, in the above step S2, according to the standard peak area, the unit peak area of each component peak of the analytical sample with a resolution less than or equal to the preset threshold is calculated, where all component peaks include nC 10 -nC 38 normal alkanes and Pr, Ph;

[0110] Specifically, the unit peak area of nCi can be calculated by the following formula:

[0111]

[0112] where Si is the unit peak area of nCi, uV·s / mg; G is the sample weight, mg; DnCi is the standard peak area of nCi, uV·s; nCi is the normal alkane with the corresponding carbon number; i is a positive integer.

[0113] The unit peak area of Pr can be calculated by the following formula:

[0114]

[0115] where SPr is the unit peak area of Pr, uV·s / mg; G is the sample weight, mg; DPr is the standard peak area of Pr, uV·s; Pr is pristane.

[0116] The unit peak area of Ph can be calculated by the following formula:

[0117]

[0118] where SPh is the unit peak area of Ph, uV·s / mg; G is the sample weight, mg; DPh is the standard peak area of Ph, uV·s; Ph is phytane.

[0119] In one embodiment, it further includes: for the calculation method of the unit peak area of the analytical sample with a resolution greater than the preset threshold, it is to divide the peak area of each component obtained by analyzing with an oil and gas component comprehensive evaluation instrument by the sample weight.

[0120] In one embodiment, in the above step S4, various derived parameters of all analytical samples are calculated, including: calculating the total peak area, calculating the retention index, calculating the degradation index, and calculating the water washing index.

[0121] The calculation methods of each derived parameter are described in detail below:

[0122] 1) The total peak area of the sample can be calculated by the following formula:

[0123]

[0124] Among them, Sz is the total peak area, uV·s / mg; Si is the unit peak area of nCi, uV·s / mg; SPr is the unit peak area of Pr, uV·s / mg; SPh is the unit peak area of Ph, uV·s / mg.

[0125] 2), Calculate the sample retention index through the following formula:

[0126]

[0127] Among them, BL is the retention index, Si is the unit peak area of nCi, uV·s / mg; SPh is the unit peak area of Ph, uV·s / mg.

[0128] 3), Calculate the sample degradation index through the following formula:

[0129]

[0130] Among them, SJ is the degradation index, and Si is the unit peak area of nCi.

[0131] 4), Calculate the sample water washing index through the following formula:

[0132]

[0133] Among them, SX is the water washing index, Si is the unit peak area of nCi, uV·s / mg; SPr is the unit peak area of Pr, uV·s / mg; SPh is the unit peak area of Ph, uV·s / mg.

[0134] In one embodiment, according to the respective derived parameters of all analyzed samples, an oil-water layer evaluation chart corresponding to each derived parameter is established. The established oil-water layer evaluation chart can be referred to Figures 2 - 4 as shown.

[0135] For example, referring to Figure 2 as shown, according to the different fluid properties to which each analyzed sample belongs, the derived parameter values of the analyzed samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the BL value, and the ordinate of the coordinate system is the Sz value, to establish the retention index evaluation chart of this oil and gas reservoir;

[0136] For example, referring to Figure 3 as shown, according to the different fluid properties to which each analyzed sample belongs, the derived parameter values of the analyzed samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the SJ value, and the ordinate of the coordinate system is the Sz value, to establish the degradation index evaluation chart of this oil and gas reservoir;

[0137] For example, referring to Figure 4 as shown, according to the different fluid properties to which each analysis sample belongs, the derived parameter values of the analysis samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the SX value, and the ordinate of the coordinate system is the Sz value, to establish the water washing index evaluation chart of this oil and gas reservoir.

[0138] The following uses specific embodiments to illustrate steps S1 - S7 of the above oil - water layer evaluation method:

[0139] 1) Determine the layer to be evaluated based on data such as cuttings, cores, sidewall cores, and gas logging

[0140] 2) Extract the starting time and ending time of each single peak of all component peaks in the pyrolysis gas chromatography parameters of all analysis samples with a separation degree greater than 1.5 within the same oil and gas reservoir as the layer to be evaluated. Use the average starting time of each component peak in this oil and gas reservoir as the standard starting time of this component peak, and use the average ending time of each component peak in this oil and gas reservoir as the standard ending time of this component peak; as shown in Table 1, where Table 1 gives partial data:

[0141] Table 1 Calculation data table of standard peak time for component peaks (partial data)

[0142]

[0143]

[0144] 3) Use the peak area between the standard starting time and the standard ending time as the standard peak area. As shown in Table 2, extract the standard peak areas of all component peaks in the pyrolysis gas chromatography parameters of the samples, and calculate the unit peak area of each component peak, where Table 2 gives partial data;

[0145] Table 2 Data table of standard peak area and unit peak area

[0146]

[0147]

[0148] 4) According to the different fluid properties within the same oil and gas reservoir as the layer to be evaluated, summarize the unit peak areas of each component peak of each analysis sample, establish the unit peak area statistical data corresponding to different fluid properties, and calculate the derived parameters (total peak area, retention index, degradation index, and water washing index) of each component peak. As shown in Table 3, where Table 3 gives partial data;

[0149] Table 3 Statistical table of unit peak area and derived parameters for different fluid properties (partial data)

[0150]

[0151]

[0152] 5) Establish an oil-water layer evaluation chart based on the calculated derived parameters;

[0153] Reference Figure 2 As shown, the abscissa of the preset coordinate system is the retention index value, and the ordinate of the coordinate system is the total peak area value. Establish the retention index evaluation chart of this oil and gas reservoir;

[0154] Different fluid properties can be represented by different symbols on the chart. For example, in the embodiment of the present invention, the oil layer data sample points are represented by ○; the oil-water coexisting layer data sample points are represented by □; the oil-bearing water layer data sample points are represented by △;

[0155] Reference Figure 3 As shown, the abscissa of the preset coordinate system is the degradation index value, and the ordinate of the coordinate system is the total peak area value. Establish the degradation index evaluation chart of this oil and gas reservoir;

[0156] Different fluid properties can be represented by different symbols on the chart. For example, in the embodiment of the present invention, the oil layer data sample points are represented by ○; the biodegraded oil layer data sample points are represented by *; the oil-water coexisting layer data sample points are represented by □; the oil-bearing water layer data sample points are represented by △;

[0157] Reference Figure 4 As shown, the abscissa of the preset coordinate system is the water washing index value, and the ordinate of the coordinate system is the total peak area value. Establish the water washing index evaluation chart of this oil and gas reservoir;

[0158] Different fluid properties can be represented by different symbols on the chart. For example, in the embodiment of the present invention, the oil layer data sample points are represented by ○; the low-saturation oil layer data samples are represented by ◇; the oil-water coexisting layer data sample points are represented by □; the oil-bearing water layer data sample points are represented by △;

[0159] In one embodiment, the chart data can be enriched according to new well test data.

[0160] The above are the steps for establishing the oil-water layer evaluation chart. The following gives three specific embodiments for evaluating the fluid properties of the well to be evaluated. Take the analysis samples from the layer to be evaluated in the well to be evaluated for unit peak area calculation and calculate the derived parameters as needed, and plot points on the corresponding chart to determine its fluid properties. The sample point to be evaluated can be represented by the graphic "☆":

[0161] In Embodiment 1, reference Figure 5As shown, Well A, 1488 - 1492m, the highest total hydrocarbon display value is 7.37%, the peak shape is full, the relative content of C1 is 99.81%, the hydrocarbon components are incomplete, the lithology is gray oil-stained siltstone, the sidewall core is grayish-brown oil-spotted siltstone, the pyrolysis analysis TPI of the sidewall core is 0.435, and Pg is 55.23mg / g, similar to the oil layer;

[0162] Reference Figure 6A As shown, for the sample at a well depth of 1490m, the pyrolysis gas chromatography analysis spectrum shows the absence of the n-alkane peak and the baseline bulges, making it difficult to calculate the peak area by conventional methods;

[0163] Therefore, it is necessary to adopt the method provided in the embodiment of the present invention. After finally identifying the component peaks, the results of the gas chromatography spectrum are for reference Figure 6B As shown;

[0164] Reference Figure 7 As shown, by using the above steps to calculate the peak areas of each component peak of the sample at a well depth of 1490m, the total peak area is calculated to be 108765uV·s / mg, the degradation index is 3.85, and a ☆ is marked on the chart to judge that this layer is a biodegraded oil layer. After testing the oil at 1487.4 - 1489.6m by using the jet pump technology, the daily oil production is 28.23t, and the crude oil viscosity reaches 4528S, which is a biodegraded oil layer.

[0165] In Example 2, referring to Figure 8 、 Figure 9 As shown, Well B, well section 2236 - 2243m, the lithology is fluorescent fine sandstone, gas logging: total hydrocarbon 6.83%, C1: 71.52%, C2: 3.96%, C3: 10.30%, the gas chromatography spectrum is nearly normal, consistent with the characteristics of the oil layer;

[0166] Reference Figure 10 As shown, by using the above steps to calculate the total peak area of the sample at a well depth of 2242m to be 442278uV·s / mg, the water washing index is 2.55, and a ☆ is used to indicate the marking position on the chart, located in the low-saturation oil layer area. After testing the oil, it is confirmed that the daily oil production is 15.92m 3 , water 5.23m 3 (emulsified water), which is a low-saturation oil layer, consistent with the chart interpretation.

[0167] In Example 3, referring to Figure 11 , Well C, well section 1716 - 1724m, the lithology is fluorescent fine sandstone, gas logging: total hydrocarbon 12.87%, C1: 98.16%, the peak shape is full, showing the characteristics of the oil layer;

[0168] Reference Figure 12A As shown, the resolution of the gas chromatography spectrum is poor, making it difficult to calculate the component peak area;

[0169] Therefore, it is necessary to adopt the method provided by the embodiments of the present invention. After finally identifying the component peaks, the results of the gas chromatography spectrum are for reference Figure 12B as shown;

[0170] for reference Figure 13 as shown, using the above step method to calculate that the total peak area of the sample at a well depth of 1719.6 m is 72278 uV·s / mg, the retention index is 0.25, and the ☆ is used to indicate the plotting position on the chart. It is located in the oil-bearing and water-bearing layer area. After oil testing, the daily oil production of this layer is 1.52 m3 and the water production is 16.15 m3. It is an oil-bearing and water-bearing layer, which is consistent with the chart interpretation.

[0171] for reference Figure 14 , based on the above oil and water layer evaluation method, the embodiments of the present invention provide an oil and water layer evaluation device, including:

[0172] A calculation module 31 extracts the start time and end time of each single peak of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a separation degree greater than a preset threshold within the same oil and gas reservoir as the layer to be evaluated, and calculates the standard start time and standard end time of all component peaks; using the standard start time and standard end time, extracts the standard peak area of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples, and calculates the unit peak area of each component peak according to the standard peak area; according to different fluid properties within the same oil and gas reservoir as the layer to be evaluated, summarizes the unit peak areas of each component peak of each analysis sample, and establishes unit peak area statistical data corresponding to different fluid properties; calculates various derived parameters of all analysis samples according to the unit peak area statistical data corresponding to different fluid properties;

[0173] An evaluation chart establishment module 32 establishes an oil and water layer evaluation chart corresponding to each derived parameter according to each derived parameter of all analysis samples;

[0174] A fluid property determination module 33 calculates the unit peak area of each component peak for the analysis sample of the layer to be evaluated in the well to be evaluated, and calculates various derived parameters according to the unit peak area of each component peak; using the oil and water layer evaluation chart corresponding to each derived parameter, projects the various derived parameters of the well to be evaluated onto the oil and water layer evaluation chart corresponding to the derived parameter, and determines the formation fluid property to which the layer to be evaluated in the well to be evaluated belongs.

[0175] Based on the above oil and water layer evaluation method, the embodiments of the present invention provide a computer storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, the oil and water layer evaluation method is implemented.

[0176] Based on the above oil-water layer evaluation method, an embodiment of the present invention provides a computing device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor implements the oil-water layer evaluation method when executing the program.

[0177] The oil-water layer evaluation method provided by the embodiment of the present invention calculates the standard peak areas of each component peak, sums the standard peak areas of the corresponding pyrolysis gas chromatography components, performs ratio calculation, establishes new parameters, and establishes an oil-water layer evaluation chart based on the new parameters and the known fluid property data obtained from well testing in the same oil and gas reservoir. Then, by plotting the derived parameters of the well to be evaluated on the chart, the fluid property of the well to be evaluated can be clearly and intuitively obtained, so as to quantitatively evaluate the oil-water layer evaluation, improve the coincidence rate of oil-water layer interpretation, and reduce the cost.

[0178] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. An oil-water layer evaluation method, characterized in that Comprising: For analysis samples with a separation degree greater than a preset threshold within the same oil and gas reservoir as the layer to be evaluated, extract the start time and end time of each individual peak of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a separation degree greater than the preset threshold, and calculate the standard start time and standard end time of each component peak; For analysis samples with a separation degree less than or equal to the preset threshold, use the calculated standard start time and standard end time of each component peak, extract the standard peak area of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a separation degree less than or equal to the preset threshold, and calculate the unit peak area of each component peak of the analysis samples with a separation degree less than or equal to the preset threshold according to the standard peak area; According to different fluid properties within the same oil and gas reservoir as the layer to be evaluated, summarize the unit peak areas of each component peak of all analysis samples, and establish unit peak area statistical data corresponding to different fluid properties; Calculate various derived parameters of all analysis samples according to the unit peak area statistical data corresponding to different fluid properties; Establish an oil-water layer evaluation chart for each derived parameter according to the various derived parameters of all analysis samples; For the analysis samples of the layer to be evaluated in the well to be evaluated, calculate the unit peak area of each component peak, and calculate various derived parameters according to the unit peak area of each component peak; Using the oil-water layer evaluation chart corresponding to each derived parameter, project the various derived parameters of the well to be evaluated onto the oil-water layer evaluation chart corresponding to the derived parameter, and determine the formation fluid property of the layer to be evaluated in the well to be evaluated.

2. The oil-water layer evaluation method according to claim 1, wherein The calculation of the standard start time and standard end time of all component peaks includes: Using the start time of each individual peak of all component peaks, calculate the average start time of each component peak within the same oil and gas reservoir as the standard start time of the component peak; Using the end time of each individual peak of all component peaks, calculate the average end time of each component peak within the same oil and gas reservoir as the standard end time of the component peak.

3. The oil-water layer evaluation method according to claim 1, wherein Calculating the unit peak area of each component peak according to the standard peak area includes: Calculating the unit peak area through the following formula: Where, Si is the unit peak area of nCi, uV·s / mg; G is the sample weight, mg; DnCi is the standard peak area of nCi, uV·s; nCi is the n-alkane with the corresponding carbon number; i is a positive integer.

4. The oil-water layer evaluation method according to claim 1, wherein Calculating the unit peak area of each component peak according to the standard peak area includes: Calculating the unit peak area through the following formula: Where SPr is the unit peak area of Pr, uV·s / mg; G is the sample weight, mg; DPr is the standard peak area of Pr, uV·s, and Pr is pristane.

5. The oil-water layer evaluation method according to claim 1, characterized in that Calculating the unit peak area of each component peak according to the standard peak area includes: Calculating the unit peak area through the following formula: Where SPh is the unit peak area of Ph, uV·s / mg; G is the sample weight, mg; DPh is the standard peak area of Ph, uV·s, and Ph is phytane.

6. The oil-water layer evaluation method according to claim 1, characterized in that Also comprising: The calculation method for the unit peak area of the analysis sample with a resolution greater than the preset threshold is to divide the peak area of each component obtained by analyzing with an integrated evaluation instrument for oil and gas components by the sample weight.

7. The oil-water layer evaluation method according to claim 1, wherein The calculation of the derived parameters includes: calculating the total peak area, calculating the retention index, calculating the degradation index, and calculating the water washing index.

8. The oil-water layer evaluation method according to claim 7, wherein The calculation of the total peak area of the sample includes: The total peak area of the sample is calculated by the following formula: Where, Sz is the total peak area, uV·s / mg; Si is the unit peak area of nCi, uV·s / mg; SPr is the unit peak area of Pr, uV·s / mg; SPh is the unit peak area of Ph, uV·s / mg.

9. The oil-water layer evaluation method according to claim 7, characterized in that The calculation of the retention index of the sample includes: The retention index of the sample is calculated by the following formula: Where, BL is the retention index, Si is the unit peak area of nCi, and SPh is the unit peak area of Ph.

10. The oil-water layer evaluation method according to claim 7, characterized in that, The calculation of the degradation index of the sample includes: The degradation index of the sample is calculated by the following formula: Where, SJ is the degradation index, and Si is the unit peak area of nCi.

11. The oil-water layer evaluation method according to claim 7, wherein The calculation of the water washing index of the sample includes: The water washing index of the sample is calculated by the following formula: Where, SX is the water washing index, Si is the unit peak area of nCi, SPr is the unit peak area of Pr, and SPh is the unit peak area of Ph.

12. The oil-water layer evaluation method according to any one of claims 8-11, characterized in that, According to the respective derived parameters of all analysis samples, an evaluation chart for oil and water layers corresponding to each derived parameter is established, including: According to the different fluid properties to which each analysis sample belongs, the values of the derived parameters of the analysis samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the BL value, and the ordinate of the coordinate system is the Sz value, to establish the retention index evaluation chart for this oil and gas reservoir; According to the different fluid properties to which each analysis sample belongs, the values of the derived parameters of the analysis samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the SJ value, and the ordinate of the coordinate system is the Sz value, to establish the degradation index evaluation chart for this oil and gas reservoir; According to the different fluid properties to which each analysis sample belongs, the values of the derived parameters of the analysis samples are set in a preset coordinate system. The abscissa of the preset coordinate system is the SX value, and the ordinate of the coordinate system is the Sz value, to establish the water washing index evaluation chart for this oil and gas reservoir.

13. An oil-water layer evaluation device, characterized in that, Including: A calculation module, for the analysis samples with a resolution greater than the preset threshold within the same oil and gas reservoir as the layer to be evaluated, extracts the starting time and ending time of each single peak of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a resolution greater than the preset threshold, and calculates the standard starting time and standard ending time of each component peak; For the analysis samples with a resolution less than or equal to the preset threshold, using the calculated standard starting time and standard ending time of each component peak, extracts the standard peak areas of all component peaks in the pyrolysis gas chromatography parameters of the analysis samples with a resolution less than or equal to the preset threshold, and calculates the unit peak area of each component peak of the analysis samples with a resolution less than or equal to the preset threshold according to the standard peak areas. According to different fluid properties within the same oil and gas reservoir as the layer to be evaluated, summarize the unit peak areas of each component peak of all analyzed samples, and establish statistical data of unit peak areas corresponding to different fluid properties; according to the statistical data of unit peak areas corresponding to different fluid properties, calculate various derived parameters of all analyzed samples; An evaluation chart building module, which builds an oil-water layer evaluation chart corresponding to each derived parameter according to the various derived parameters of all analyzed samples; A fluid property determination module, which calculates the unit peak area of each component peak for the analyzed sample of the layer to be evaluated in the well to be evaluated, and calculates various derived parameters according to the unit peak area of each component peak; uses the oil-water layer evaluation chart corresponding to the various derived parameters to project the various derived parameters of the well to be evaluated onto the oil-water layer evaluation chart corresponding to the derived parameters, and determines the formation fluid property to which the layer to be evaluated in the well to be evaluated belongs.

14. A computer storage medium, characterized in that, A computer storage medium stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, the oil-water layer evaluation method described in any one of claims 1-12 is implemented.

15. A computing device, characterized in that, Including: A memory, a processor, and a computer program stored on the memory and executable on the processor, and when the processor executes the program, the oil-water layer evaluation method described in any one of claims 1-12 is implemented.

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