Calculation method for homogeneous temperature of fluid inclusion homogeneous as liquid phase

Abstract

The invention discloses a method for calculating the homogeneous temperature of a fluid inclusion homogeneous as a liquid phase. The method comprises the following steps: by heating a rock slice of a target fluid inclusion, acquiring multiple groups of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data after a gas phase in the fluid inclusion begins to change; according to the obtained multiple sets of fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data, a relation model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature is established; and calculating the uniform temperature of the target fluid inclusion according to the relation model of the gas-liquid ratio of the fluid inclusion and the temperature of the fluid inclusion. According to the method, the time for obtaining the uniform temperature of the liquid-phase fluid inclusion is shortened, the efficiency for obtaining the uniform temperature of the fluid inclusion is improved, and particularly, the method has good practical value in the field of calculation of the uniform temperature of the high-temperature and ultrahigh-temperature fluid inclusion.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluid inclusion, in particular to a calculation method of fluid inclusion homogenization temperature of liquid phase. BACKGROUND

[0002] The fluid inclusion homogenization temperature refers to the temperature of two-phase or multi-phase fluid inclusion when the underground mineral rock is captured. The fluid inclusion homogenization temperature can be used in the oil industry, mining industry and deep environment research of the earth, and in combination with other data such as burial history and thermal history, the temperature of the oil and gas reservoir or the vein when it is formed in the deep underground can be inferred, and the geological age of the oil and gas reservoir or the vein can be inferred, thereby providing technical guidance for oil and gas and various solid mineral exploration and development.

[0003] The conventional fluid inclusion homogenization temperature testing technology is generally as follows: under the present room temperature condition, the instantaneous temperature of two-phase or multi-phase fluid inclusion when it is heated to be homogeneous single-phase inclusion is the fluid inclusion homogenization temperature. However, heating from room temperature to the fluid inclusion homogenization temperature is a time-consuming and laborious fine work, and usually takes a long time. Especially in deep and ultra-deep strata, the fluid inclusion has an ultra-high capture temperature (homogenization temperature), and if there is interference of deep thermal fluid, the capture temperature will be higher, and it will take a longer time to heat from room temperature to the fluid inclusion homogenization temperature. If a rock core sample is taken from an ultra-deep layer of 8000 m, and the low temperature gradient is low (2.3 ℃ / 100 m, and the ground temperature is 16 ℃), the present bottom hole temperature is close to about 200 ℃, and if the geothermal gradient is higher, the bottom hole temperature will be much higher than 200 ℃. If the temperature of the fluid inclusion when it is captured is about 180 ℃, when the fluid inclusion homogenization temperature is tested, it is heated from room temperature 20 ℃ to 180 ℃, and if the heating rate is 2 ℃ / min, it will take about 1 hour and 20 minutes to test the homogenization temperature of a single fluid inclusion, which is very time-consuming and low in efficiency. Therefore, it is an important problem to be solved to improve the acquisition efficiency of the fluid inclusion homogenization temperature. SUMMARY

[0004] In view of the above problems, the present application is proposed to provide a calculation method of fluid inclusion homogenization temperature of liquid phase, which overcomes the above problems or at least partially solves the above problems.

[0005] In a first aspect, the embodiments of the present application provide a calculation method of fluid inclusion homogenization temperature of liquid phase, comprising:

[0006] obtaining a plurality of groups of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data of the fluid inclusion after the gas phase of the fluid inclusion begins to change by heating the rock thin section of the target fluid inclusion;

[0007] According to the obtained multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data, a relationship model of fluid inclusion gas-liquid ratio and fluid inclusion temperature is established;

[0008] According to the relationship model of fluid inclusion gas-liquid ratio and fluid inclusion temperature, the homogenization temperature of the target fluid inclusion is calculated.

[0009] In one embodiment, the multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data obtained after the internal gas phase of the fluid inclusion begins to change include:

[0010] The rock thin section is placed in a hot-cold stage for heating, and the temperature information of the hot-cold stage is recorded during the heating process, and a micrograph of the rock thin section corresponding to the temperature information is synchronously taken;

[0011] The area ratio or volume ratio of the gas phase and the liquid phase is calculated through the area or volume of the gas phase and the liquid phase in the micrograph of the rock thin section, to obtain the fluid inclusion gas-liquid ratio data corresponding to the temperature information.

[0012] In one embodiment, the area or volume of the gas phase and the liquid phase in the micrograph of the rock thin section is calculated by a graphics processing software.

[0013] In one embodiment, according to the obtained multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data, a relationship model of fluid inclusion gas-liquid ratio and fluid inclusion temperature is established, including:

[0014] A linear regression analysis is performed on the obtained multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data, to establish multiple relationship curves of the fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data;

[0015] The regression coefficients of each relationship curve are calculated respectively;

[0016] According to the regression coefficients of the multiple relationship curves, a relationship curve corresponding to a critical point where the regression coefficient reaches stability and steadily increases is selected from the multiple relationship curves as a curve of the relationship model of fluid inclusion gas-liquid ratio and fluid inclusion temperature.

[0017] In one embodiment, a regression analysis is performed on the obtained multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data, to establish multiple relationship curves of the fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data, including:

[0018] According to the fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data to be fitted, the fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data with different data amounts are fitted respectively to obtain a plurality of relationship curves of the fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data.

[0019] In one embodiment, according to the regression coefficients of the plurality of relationship curves, a relationship curve with the highest credibility is selected from the plurality of relationship curves as a curve of the relationship model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature, including:

[0020] According to the change rule of the regression coefficients, a critical point at which the regression coefficient reaches stability and steadily increases is found, and a relationship curve corresponding to the critical point is determined as the curve of the relationship model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature.

[0021] In one embodiment, according to the curve of the relationship model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature, the uniform temperature of the fluid inclusion is calculated, including:

[0022] According to the curve of the relationship model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature, a temperature value corresponding to a case where the gas-liquid ratio of the fluid inclusion is 0 is calculated, and the temperature value is determined as the uniform temperature of the fluid inclusion.

[0023] In one embodiment, during the heating process, temperature information of a cold-hot stage is recorded, and a micrograph of a rock slice corresponding to the temperature information is synchronously photographed, including:

[0024] The temperature value at which the gas phase of the fluid inclusion starts to jump or shrink after being heated is recorded;

[0025] While the temperature value is recorded, a micrograph of the rock slice is photographed.

[0026] In one embodiment, the rock slice is placed in the cold-hot stage for heating, including:

[0027] An initial heating speed is used to heat the cold-hot stage;

[0028] When the gas phase starts to jump or shrink, the heating speed of the cold-hot stage is slowed down;

[0029] When the speed at which the gas phase jumps or shrinks becomes faster, the heating speed of the cold-hot stage is further slowed down.

[0030] In one embodiment, the thickness of the rock slice of the target fluid inclusion is in a range of 80-100 μm.

[0031] The above technical solutions provided by the embodiments of the present application have at least the following beneficial effects:

[0032] The method for calculating the uniform temperature of the liquid-phase fluid inclusion provided by the embodiment of the present application uses a rock thin section of a target fluid inclusion to obtain fluid inclusion temperature data and fluid inclusion gas-liquid ratio data after the internal gas phase of the fluid inclusion starts to change, and uses the temperature data and the gas-liquid ratio data to establish a model, so that the uniform temperature of the target fluid inclusion is calculated through the model, without simply relying on the heating process test to obtain the uniform temperature as in the prior art, thereby shortening the time for obtaining the uniform temperature, improving the efficiency of obtaining the uniform temperature, and saving the energy consumption of the heating process.

[0033] In addition, according to the change rule of the regression coefficient, a critical point where the regression coefficient reaches stability and steadily increases is found, a relationship curve corresponding to the critical point is determined as the curve of the relationship model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature, the relationship between the gas-liquid ratio and the temperature is measured according to the regression coefficient, the relationship curve with the highest credibility is selected, and the accuracy of the uniform temperature calculation is also ensured.

[0034] Additional features and advantages of the application will be set forth in the description that follows, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the application. The objectives and other advantages of the application will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

[0035] The technical solutions of the present application will be further described in detail below with the help of the accompanying drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0036] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, illustrate embodiments of the present application, and are used to explain the present application together with the embodiments of the present application, and do not constitute a limitation on the present application. In the drawings:

[0037] Figure 1 The flowchart of the uniform temperature calculation method in the embodiment of the present application;

[0038] Figure 2 The flowchart of obtaining the inclusion temperature and gas-liquid ratio data in the embodiment of the present application;

[0039] Figure 3 The flowchart of establishing the relationship model of the fluid inclusion gas-liquid ratio and the temperature in the embodiment of the present application;

[0040] Figure 4 The schematic diagram of the gas-liquid two-phase inclusion in the embodiment of the present application;

[0041] Figure 5 The micrograph of the change of the fluid inclusion gas-liquid ratio with temperature in the embodiment of the present application;

[0042] Figure 6 Fig. 2 is a schematic diagram of the regression relationship between the temperature of the inclusion and the gas-liquid ratio under different data amounts in an embodiment of the present application;

[0043] Figure 7 Fig. 3 is a curve diagram of the regression coefficient corresponding to the regression formula under different data amounts in an embodiment of the present application. DETAILED DESCRIPTION

[0044] Exemplary embodiments of the present disclosure will be described in greater detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be accurately conveyed to those skilled in the art.

[0045] The homogeneous temperature of the fluid inclusion reflects the temperature of the fluid captured in the mineral under the ground. The fluid inclusion captured in the liquid phase under the ground needs to be heated to the temperature of the fluid captured under the ground at room temperature. During the heating process, the fluid inclusion changes from two-phase, three-phase or multi-phase state to homogeneous liquid phase state, so that the homogeneous temperature of the fluid inclusion is obtained. In the prior art, in order to make the fluid in the fluid inclusion fully homogeneous, the heating speed is usually controlled to be relatively slow, so that the homogeneous temperature of the fluid inclusion measured by the conventional method takes a long time and the work efficiency is relatively low.

[0046] Based on the above problems, an embodiment of the present application provides a calculation method of the homogeneous temperature of the fluid inclusion with homogeneous liquid phase. Referring to Fig. 1, the calculation method of the homogeneous temperature includes the following steps: Figure 1

[0047] S11, obtaining a plurality of groups of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data after the gas phase in the fluid inclusion begins to change by heating the rock thin section of the target fluid inclusion;

[0048] S12, establishing a relationship model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature according to the plurality of groups of fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data;

[0049] S13, calculating the homogeneous temperature of the target fluid inclusion according to the relationship model of the fluid inclusion gas-liquid ratio and the fluid inclusion temperature.

[0050] ​The method for calculating the homogenization temperature of a liquid-phase fluid inclusion provided by the embodiment of the present application uses a rock slice of a target fluid inclusion to obtain fluid inclusion temperature data and fluid inclusion gas-liquid ratio data after the gas phase in the fluid inclusion starts to change, and uses the temperature data and the gas-liquid ratio data to establish a model, so that the homogenization temperature of the target fluid inclusion can be calculated through the model, without simply relying on the heating process to test the homogenization temperature as in the prior art, thereby shortening the time for obtaining the homogenization temperature, improving the efficiency of obtaining the homogenization temperature, and saving the energy consumption of the heating process.

[0051] In one embodiment of the present application, the rock slice of the target fluid inclusion can be obtained by preparing the rock slice of the target fluid inclusion, polishing the rock slice sample of the fluid inclusion on both sides, and controlling the thickness of the rock slice of the fluid inclusion to be 80-100 μm.

[0052] The fluid inclusion in the rock slice is observed under an optical microscope and selected, and two-phase or multi-phase (both containing a gas phase) fluid inclusions can be selected as target fluid inclusions. The type of the target fluid inclusion is not limited to a brine inclusion, a hydrocarbon (oil and gas) inclusion, a CO2inclusion, a N2inclusion, a H2inclusion, and other gas-liquid two-phase, three-phase or multi-phase inclusions, etc. In the embodiment of the present application, a two-phase (gas phase + liquid phase) fluid inclusion can be selected as a target fluid inclusion, and a micrograph of one two-phase target fluid inclusion can be seen from Figure 4 .

[0053] Further, in the step S11, a plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data after the gas phase in the fluid inclusion starts to change are obtained by heating the rock slice of the target fluid inclusion, which can be achieved by the following process: Figure 2 .

[0054] S21, the rock slice is placed into a cold-hot stage for heating, and the temperature information of the cold-hot stage is recorded during the heating process, and a micrograph of the rock slice corresponding to the temperature information is synchronously taken;

[0055] S22, the area ratio or volume ratio of the gas phase and the liquid phase is calculated through the area or volume of the gas phase and the liquid phase in the micrograph of the rock slice, so as to obtain the fluid inclusion gas-liquid ratio data corresponding to the temperature information.

[0056] In one embodiment, in the step S21, the rock slice is placed into a cold-hot stage for heating, and the heating process in the embodiment of the present application can be, for example:

[0057] 1. An initial heating speed is used to heat the cold-hot stage;

[0058] 2. When the gas phase starts to jump or shrink, slow down the heating speed of the hot stage;

[0059] 3. When the speed of the gas phase jumping or shrinking becomes faster, further slow down the heating speed of the hot stage.

[0060] In the step S21, the temperature information of the hot stage during the heating process is recorded, and the microscopic photos of the rock slice corresponding to the temperature information are taken synchronously, and in the embodiment of the present application, the temperature value after the gas phase of the fluid inclusion starts to jump or shrink during the heating process is recorded; at the same time of recording the temperature value, the microscopic photos of the rock slice are taken.

[0061] In the embodiment of the present application, the area or volume of the gas phase and the liquid phase in the microscopic photos of the rock slice can be calculated by the graphic processing software.

[0062] The graphic processing software can be Photoshop or Coreldraw, etc.

[0063] In one embodiment, the temperature information of the hot stage during the heating process is recorded in the step S21, and the microscopic photos of the rock slice corresponding to the temperature information are taken synchronously, and in the specific implementation, when the hot stage is heated, the target fluid inclusion is observed by using the optical microscope at the same time, and the test temperature is recorded once every time the hot stage is raised by a preset temperature, for example, 1℃, and the microscopic photos of the target fluid inclusion are taken at the same time.

[0064] In one embodiment, the temperature value after the gas phase of the target fluid inclusion starts to jump or shrink is selected, for example, the test temperature can be recorded once every 1℃ after the gas phase starts to change, and the microscopic photos of the target fluid inclusion are taken at the same time, so that a plurality of groups of temperature data and the corresponding microscopic photos are obtained, the microscopic photos are processed to obtain the corresponding gas-liquid ratio data, and finally a plurality of groups of data pairs of temperature data and gas-liquid ratio data are obtained.

[0065] In one embodiment, the gas-liquid ratio of the fluid inclusion represents the area ratio or volume ratio of the gas phase and the liquid phase in the fluid inclusion. In one embodiment of the present application, the area ratio of the gas phase and the liquid phase in the microscopic photos is simplified as the gas-liquid ratio of the fluid inclusion in the specific implementation of the step S22. The image processing software is used to calculate the gas phase area and the liquid phase area of the target fluid inclusion at the corresponding temperature, which are respectively denoted as S g , S l , and the gas-liquid ratio S of the fluid inclusion is calculated as:

[0066] S=(S g / S l )×100.

[0067] In one embodiment, in step S12, a relationship model between the fluid inclusion gas-liquid ratio and the fluid inclusion temperature is established according to the obtained multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data, and the relationship model is referred to as Figure 3 As shown in the figure, the process can be implemented as follows:

[0068] S31, linear regression analysis is performed on the obtained multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data to establish multiple relationship curves of the fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data;

[0069] S32, the regression coefficient of each relationship curve is calculated respectively;

[0070] S33, according to the regression coefficients of the multiple relationship curves, the relationship curve with the highest credibility is selected from the multiple relationship curves as the curve of the relationship model between the fluid inclusion gas-liquid ratio and the fluid inclusion temperature.

[0071] Linear regression analysis is a statistical method mainly used to study how one or more independent variables affect a dependent variable. The core purpose of this method is to quantify the relationship between the independent variable and the dependent variable, and to establish a mathematical model to predict the possible value of the dependent variable given the value of the independent variable. In regression analysis, the simplest and most common form is univariate linear regression, in which there is only one independent variable and one dependent variable, and the relationship between them is described by a best-fit curve.

[0072] In the embodiment of the application, a univariate linear regression relationship model between the fluid inclusion gas-liquid ratio and the fluid inclusion temperature can be established, and in the corresponding mathematical expression, the independent variable is the fluid inclusion temperature x, and the dependent variable is the fluid inclusion gas-liquid ratio y. The univariate linear regression relationship model can be written as a linear regression equation as follows:

[0073] y=β1x+β0

[0074] Wherein, y is the fluid inclusion gas-liquid ratio, which is the dependent variable; x is the fluid inclusion temperature, which is the independent variable; β1 is the slope, and β0 is the intercept.

[0075] The calculation formula of β1 is as follows:

[0076]

[0077] Wherein, X i represents the temperature value of the i-th group, Y i represents the gas-liquid ratio value of the i-th group, and n represents the total number of data groups, is the average value of all group temperature values, The calculation formula of β0 is as follows:

[0078]

[0079] is the average value of all group gas-liquid ratio values, The calculation formula of is as follows:

[0080]

[0081] According to β1, The calculation formula of β0 is as follows:

[0082]

[0083] In the step S31, the obtained multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data are subjected to linear regression analysis to establish multiple relationship curves of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data. According to the multiple sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data to be fitted, different data amounts of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data are fitted respectively to obtain multiple relationship curves of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data.

[0084] According to the regression coefficients of the multiple relationship curves, a relationship curve with the highest credibility is selected from the multiple relationship curves. In a specific implementation, the relationship curve can be selected by the following manner:

[0085] According to the change rule of the regression coefficients, a critical point at which the regression coefficient reaches stability and steadily increases is found, and a relationship curve corresponding to the critical point is determined as a curve of a relationship model of fluid inclusion gas-liquid ratio and fluid inclusion temperature.

[0086] In an embodiment, in the step S32, the regression coefficient of each relationship curve is calculated respectively. For the one-variable linear regression model, the regression coefficient R 2 The calculation formula of R

[0087]

[0088] wherein, RSS refers to residual sum of squares, and the calculation formula is as follows:

[0089]

[0090] TSS refers to total sum of squares, and the calculation formula is as follows:

[0091]

[0092] wherein, y irepresents the observed gas-liquid ratio of the i-th fluid inclusion; represents the i-th fluid inclusion gas-liquid ratio predicted by the relationship model; represents the average value of the observed fluid inclusion gas-liquid ratio.

[0093] Regression coefficient R 2 The value of the regression coefficient R is between 0 and 1, 1 indicates that the relationship model perfectly fits the data, i.e. all observation points are on the regression line; 0 indicates that the fitting degree of the relationship model to the data is very poor, and the regression curve basically cannot explain the change of the dependent variable. The closer the value of the regression coefficient R 2 to 1, the better the fitting effect of the relationship model to the data.

[0094] In one embodiment, in the step S13 described above, the temperature value corresponding to the gas-liquid ratio of 0 of the fluid inclusion is calculated through the curve of the relationship model of the gas-liquid ratio of the fluid inclusion and the temperature of the fluid inclusion, and is determined as the homogenization temperature of the fluid inclusion.

[0095] Taking the formula y = β1x + β0 as an example, when y is 0, the value of x is solved, which is the homogenization temperature of the fluid inclusion.

[0096] The calculation method of the homogenization temperature of the fluid inclusion with the homogenization liquid phase is described below with a specific example.

[0097] 1. Prepare a rock slice of the target fluid inclusion.

[0098] Select the core of the target layer of the target well site in the study area for fluid inclusion preparation, and perform double-face sectioning on the rock slice sample, controlling the thickness of the target fluid inclusion rock slice to be 80-100 μm.

[0099] 2. Select the target fluid inclusion.

[0100] Under the optical microscope, observe and select the target fluid inclusion in the rock slice. In this example, two-phase (gas phase + liquid phase) fluid inclusions are taken as the target fluid inclusion, which can be specifically referred to in Figure 4 .

[0101] 3. Heat the target fluid inclusion.

[0102] Cut thin slices of rock containing target fluid inclusions so that the slices are large enough to be placed on a hot / cold stage for heating. Heat the hot / cold stage with an initial heating rate of 3°C / min. When bubbles begin to shrink or jump, slow the heating rate to 2°C / min. When bubbles jump or shrink rapidly, further reduce the heating rate to 1°C / min. Heat the hot / cold stage while observing the target fluid inclusions using an optical microscope. Record the test temperature every time the hot / cold stage rises by 1°C. Simultaneously, take micrographs of the target fluid inclusions. See [Image of target fluid inclusions taken during heating] for some micrographs of the target fluid inclusions taken during heating. Figure 5 .

[0103] 4. Calculate the gas-liquid ratio of the target fluid inclusion.

[0104] Select the temperature and corresponding micrograph when the gas phase inside the target fluid inclusion begins to shrink or jump. Generally, select 6 to 10 temperature data points after the change and their corresponding micrographs. In this example, the gas-liquid ratio of the fluid inclusion is simplified to the area ratio of the gas phase to the liquid phase in the micrograph. Use graphics processing software (such as Photoshop or Coreldraw, etc.) to calculate the gas phase area and liquid phase area at the corresponding temperature, and calculate the gas-liquid ratio of the fluid inclusion at the corresponding temperature based on the ratio of the gas phase area to the liquid phase area. The first 10 temperatures at which the gas phase of the target fluid inclusion begins to change and the corresponding gas-liquid ratio data recorded in this example are shown in Table 1, and the temperature increase step is set to 1°C.

[0105] Table 1 Target fluid inclusion temperature and corresponding gas-liquid ratio

[0106]

[0107] 5. Calculate the homogenization temperature of the target fluid inclusion.

[0108] According to the collected temperature data and the corresponding gas-liquid ratio data, the data are fitted under different data volume conditions. Figure 6 As shown, in this example, 3 groups of data are fitted (the first to third groups of fluid inclusion temperature data are fitted with the corresponding fluid inclusion gas-liquid ratio data), 4 groups of data are fitted (the first to fourth groups of fluid inclusion temperature data are fitted with the corresponding fluid inclusion gas-liquid ratio data), 5 groups of data are fitted (the first to fifth groups of fluid inclusion temperature data are fitted with the corresponding fluid inclusion gas-liquid ratio data), and so on, until 10 groups of data are fitted, and the corresponding data quantity relationship curves and regression coefficients are obtained.

[0109] The regression formula and regression coefficient obtained by fitting 3 groups of data, 4 groups of data, 5 groups of data, 6 groups of data, 7 groups of data, 8 groups of data, 9 groups of data and 10 groups of data are shown in Table 2.

[0110] Table 2 Regression formula and regression coefficient calculated by different data

[0111]

[0112] According to all the regression coefficients obtained, the regression coefficient change curve is obtained as shown in Figure 7 In this example, the regression coefficient reaches stability after 6 groups of data and the regression coefficient steadily increases to approach 1, indicating that the correlation between the target fluid inclusion temperature and the gas-liquid ratio is good, and the regression curve has high reliability. Therefore, the regression formula obtained by fitting 6 groups of data in this example is y = -0.5143x + 51.771, the regression coefficient is 0.9975, and when the target fluid inclusion gas-liquid ratio y is 0, the corresponding target fluid inclusion homogenization temperature is calculated to be 100.66℃, and thus the entire implementation process of this example is completed. In order to verify the accuracy of the target fluid inclusion homogenization temperature calculated in this example, the rock thin section of the target fluid inclusion is specially heated until the target fluid inclusion homogenizes to a liquid phase state. The test results show that the target fluid inclusion reaches a homogeneous liquid phase at a temperature of 101℃. The error between the result calculated by the above method and the actual measurement result is 0.33%, and the error is less than 1%, indicating that the calculation result is relatively accurate and can reflect the true fluid inclusion homogenization temperature.

[0113] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application also intends to include these modifications and variations.

Claims

1. A method of calculating the uniform temperature of a fluid inclusion that is homogeneous in the liquid phase, characterized by, The method comprises the following steps: obtaining a plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data after the gas phase in the fluid inclusion begins to change by heating a rock slice of a target fluid inclusion; establishing a fluid inclusion gas-liquid ratio and fluid inclusion temperature relationship model according to the obtained plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data; calculating the homogenization temperature of the target fluid inclusion according to the fluid inclusion gas-liquid ratio and fluid inclusion temperature relationship model.

2. The method of claim 1, wherein, The method for obtaining a plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data after the gas phase in the fluid inclusion begins to change comprises the following steps: placing the rock slice into a cold-hot table for heating, recording the temperature information of the cold-hot table during the heating process, and synchronously taking a micrograph of the rock slice corresponding to the temperature information; calculating the area ratio or volume ratio of the gas phase and the liquid phase through the area or volume of the gas phase and the liquid phase in the micrograph of the rock slice, to obtain the fluid inclusion gas-liquid ratio data corresponding to the temperature information.

3. The method of claim 2, wherein, The area or volume of the gas phase and the liquid phase in the micrograph of the rock slice is calculated by a graphics processing software.

4. The method of claim 1, wherein, The method for establishing a fluid inclusion gas-liquid ratio and fluid inclusion temperature relationship model according to the obtained plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data comprises the following steps: performing linear regression analysis on the obtained plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data to establish a plurality of relationship curves of the fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data; calculating the regression coefficients of each relationship curve respectively; selecting the relationship curve with the highest credibility from the plurality of relationship curves as the curve of the fluid inclusion gas-liquid ratio and fluid inclusion temperature relationship model according to the regression coefficients of the plurality of relationship curves.

5. The method of claim 4, wherein, The method for performing regression analysis on the obtained plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data to establish a plurality of relationship curves of the fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data comprises the following steps: fitting the fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data with different data amounts respectively according to the plurality of sets of fluid inclusion temperature data and corresponding fluid inclusion gas-liquid ratio data to be fitted, to obtain a plurality of relationship curves of the fluid inclusion temperature data and the corresponding fluid inclusion gas-liquid ratio data.

6. The method of claim 4, wherein, The method for selecting the relationship curve with the highest credibility from the plurality of relationship curves as the curve of the fluid inclusion gas-liquid ratio and fluid inclusion temperature relationship model according to the regression coefficients of the plurality of relationship curves comprises the following steps: finding a critical point at which the regression coefficient reaches stability and steadily increases according to the change rule of the regression coefficient, and determining the relationship curve corresponding to the critical point as the curve of the fluid inclusion gas-liquid ratio and fluid inclusion temperature relationship model.

7. The method of claim 1, wherein, The method for calculating the homogenization temperature of the fluid inclusion according to the curve of the fluid inclusion gas-liquid ratio and fluid inclusion temperature relationship model comprises the following steps: The temperature value corresponding to the gas-liquid ratio of 0 of the fluid inclusion is calculated through the curve of the relationship model of the gas-liquid ratio of the fluid inclusion and the temperature of the fluid inclusion, and is determined as the homogenization temperature of the fluid inclusion.

8. The method of claim 2, wherein, The temperature information of the cold and hot stage is recorded during the heating process, and the micrograph of the rock slice corresponding to the temperature information is synchronously photographed, including: The temperature value after the gas phase of the fluid inclusion starts to jump or shrink is recorded; The micrograph of the rock slice is photographed while the temperature value is recorded.

9. The method of claim 2, wherein, The rock slice is placed into the cold and hot stage for heating, including: The cold and hot stage is heated at an initial heating speed; When the gas phase starts to jump or shrink, the heating speed of the cold and hot stage is slowed down; When the speed of the gas phase jumping or shrinking becomes faster, the heating speed of the cold and hot stage is further slowed down.

10. The method of any one of claims 1-8, wherein, The thickness of the rock slice of the target fluid inclusion ranges from 80 to 100 μm.

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