Method, device, equipment and medium for measuring in-situ oil content and gas content of shale oil

Abstract

The invention discloses a shale oil in-situ oil and gas content measuring method, device, equipment and medium, and relates to the technical field of shale gas exploration and development.The method includes the steps that on-site freezing pyrolysis and analytic gas testing are conducted on core samples obtained after pressure maintaining coring and conventional coring, and a free oil drilling loss coefficient and an analytic gas loss coefficient are calculated respectively; according to the method, hydrocarbon loss in the experiment process is quantified, hydrocarbon loss is further corrected in combination with light hydrocarbon loss coefficients and heavy hydrocarbon correction coefficients placed for different time, hydrocarbon loss difference under different experiment steps and different experiment methods is considered in the process, and underground in-situ oil content and gas content are recovered respectively. And finally, the oil content and the gas content under the in-situ formation condition are recovered, and the evaluation accuracy of the oil content and the gas content of the shale is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of shale gas exploration and development, and particularly relates to a method, device, equipment and medium for measuring in-situ oil and gas content in shale oil. Background Art

[0002] As a key component of unconventional oil and gas resources, the oil-bearing property of shale oil is an important index for shale oil selection evaluation and resource volume calculation, which directly affects the developability and commercial value of the target interval. Therefore, accurately obtaining the oil content in shale is a key step in the process of shale oil exploration and development.

[0003] Currently, due to the advantages of simple operation and rapid analysis, the rock pyrolysis method has become one of the main technical means for characterizing the shale oil content; the free hydrocarbon parameter S1 (C7-C 32 components) generated during the pyrolysis process is an important geochemical index, which is widely used to calculate the oil-bearing property of shale and evaluate the content of movable oil; it can be seen that the current methods are limited to obtaining a single free hydrocarbon parameter S1 value, and do not comprehensively consider various factors during the hydrocarbon loss process, such as oil and gas loss during the core extraction process, light hydrocarbon loss degree, and heavy hydrocarbon correction, etc., thus affecting the accurate evaluation of the oil-bearing and gas-bearing properties of shale. Summary of the Invention

[0004] The embodiments of the present invention provide a method, device, equipment and medium for measuring in-situ oil and gas content in shale oil, which can solve the problem in the prior art that the current methods are limited to obtaining a single free hydrocarbon parameter S1 value, and do not comprehensively consider various factors during the hydrocarbon loss process, such as oil and gas loss during the core extraction process, light hydrocarbon loss degree, and heavy hydrocarbon correction, etc., thus affecting the accurate evaluation of the oil-bearing and gas-bearing properties of shale.

[0005] The embodiments of the present invention provide a method for measuring in-situ oil and gas content in shale oil, including the following steps: Obtain a first core sample of shale by using the pressure-maintaining core sampling method, and obtain the free oil content and gas content of the first core sample; Obtain a second core sample of shale by using the conventional core sampling method, obtain the residual oil content after core extraction, pyrolysis hydrocarbon content and residual gas content after core extraction of the second core sample, and obtain the residual free oil content of the second core sample; According to the free oil content and the residual oil content after core extraction, obtain the free oil core extraction loss coefficient characterizing the free oil loss of the core sample; according to the gas content and the residual gas content after core extraction, obtain the desorbed gas loss coefficient characterizing the gas loss of the core sample; according to the residual oil content after core extraction and the residual free oil content, obtain the light hydrocarbon loss coefficient characterizing the light hydrocarbon loss of the core sample; Obtain the heavy hydrocarbon content and kerogen content of the second core sample, and obtain the heavy hydrocarbon correction coefficient characterizing the heavy hydrocarbon loss of the core sample according to the heavy hydrocarbon content and the kerogen content; Based on the residual free oil content, light hydrocarbon loss coefficient, free oil loss coefficient during coring, pyrolytic hydrocarbon content, heavy hydrocarbon correction coefficient, analytical gas loss coefficient, and residual gas content during coring, the oil and gas content under in-situ formation conditions of shale oil is obtained.

[0006] Preferably, the obtaining of the free oil content and gas content includes: Using pressure-maintaining coring to obtain two core samples, namely Sample A and Sample B; Sealing Sample A of the core samples at ultra-low temperature, under liquid nitrogen injection, performing core sectioning and airtight crushing of the core samples into powder samples with a mesh size of 200, putting the core powder samples into a pyrolyzer, and obtaining the free oil content S1 at a constant temperature of 300 °C for 3 min; Sealing Sample B of the core samples at ultra-low temperature, under continuous liquid nitrogen injection, performing core sectioning of the core samples, using an analytical device to measure and record the analytical gas detection parameters and corresponding time points at a set analytical temperature, obtaining an analytical time - analytical gas volume data table, calculating the analytical gas content, crushing the core samples after analysis and then analyzing again to obtain a residual gas test record, calculating the gas content and loss gas content, and the sum of the analytical gas content, gas content, and loss gas content is the gas content V.

[0007] Preferably, the obtaining of the residual oil content during coring, pyrolytic hydrocarbon content, and residual gas content during coring includes: Using conventional coring to obtain multiple core samples, and taking two of the core samples as Sample C and Sample D; Sealing Sample C of the core samples at ultra-low temperature, under liquid nitrogen injection, performing core sectioning and airtight crushing of the core samples into powder samples with a mesh size of 200, putting the core powder samples into a pyrolyzer, and obtaining the residual oil content during coring S1 at a constant temperature of 300 °C for 3 min * ; and heating to 600 °C at a heating rate of 25 °C per minute to obtain the pyrolytic hydrocarbon content S2; Sealing Sample D of the core samples at ultra-low temperature, under continuous liquid nitrogen injection, performing core sectioning of the core samples, using an analytical device to measure and record the analytical gas detection parameters and corresponding time points at a set analytical temperature to obtain an analytical time - analytical gas volume data table, calculating the analytical gas content, crushing the core samples after analysis and then analyzing again to obtain a residual gas test record, calculating the gas content and loss gas content, and the sum of the analytical gas content, gas content, and loss gas content is the residual gas content during coring V * .

[0008] Preferably, the obtaining of the residual free oil content includes: For the remaining core samples after conventional coring, they are respectively placed at room temperature for 1 hour, 2 hours, 4 hours, 8 hours, 24 hours, 48 hours, 96 hours, 192 hours, and 360 hours and then crushed. The core powder samples are put into a pyrolyzer and kept at a constant temperature of 300 °C for 3 minutes to obtain the residual free oil content S1 corresponding to each time point. (1) , S1 (2) , S1 (4) ……S1 (360) , and the residual free oil content S1 corresponding to each time point (1) , S1 (2) , S1 (4) ……S1 (360) is taken as the residual free oil content .

[0009] Preferably, the acquisition method of the free oil extraction loss coefficient is as follows: ; wherein: S 1 represents the free oil content; S 1 * represents the residual oil content after extraction; represents the core sample density; The acquisition method of the analytical gas loss coefficient is as follows: ; wherein: V represents the gas content; V * represents the residual gas content after extraction; The acquisition method of the light hydrocarbon loss coefficient is as follows: ; wherein: S 1 * represents the residual oil content after extraction; represents the residual free oil content corresponding to each time point.

[0010] Preferably, the acquisition process of the heavy hydrocarbon correction coefficient includes: Obtain a core sample from conventional coring. After crushing it at room temperature, put the core powder sample into a pyrolyzer. Keep it at a constant temperature of 200 °C for 1 minute to obtain the light oil content, then increase the temperature at a rate of 25 °C per minute to 350 °C and keep it at a constant temperature for 1 minute to obtain the light and medium oil. Continue to increase the temperature at the same rate to 450 °C and keep it at a constant temperature for 1 minute to obtain the heavy hydrocarbon content S 2-1 , and finally increase the temperature to 600 °C at the same rate again to obtain the kerogen content S 2-2 ; According to the heavy hydrocarbon content S2-1 and kerogen content S 2-2 Obtain a heavy hydrocarbon correction coefficient, and the heavy hydrocarbon correction coefficient is obtained in the following way: .

[0011] Preferably, the oil and gas content under the in-situ formation conditions of the shale oil Y is obtained in the following way: ; Wherein: represents the residual free oil content; represents the light hydrocarbon loss coefficient; represents the free oil loss coefficient during core drilling; represents the pyrolysis hydrocarbon content; represents the heavy hydrocarbon correction coefficient; represents the analytical gas loss coefficient; V * represents the residual gas content during core drilling.

[0012] An embodiment of the present invention further provides a device for measuring the in-situ oil and gas content of shale oil, including: An experimental module, which is used to obtain the first core sample of shale by the pressure-retaining core-taking method, and obtain the free oil content and gas content of the first core sample; Obtain the second core sample of shale by the conventional core-taking method, obtain the residual oil content during core drilling, pyrolysis hydrocarbon content and residual gas content during core drilling of the second core sample, and obtain the residual free oil content of the second core sample; A hydrocarbon loss module, which is used to obtain the free oil loss coefficient during core drilling representing the free oil loss of the core sample according to the free oil content and the residual oil content during core drilling; obtain the analytical gas loss coefficient representing the gas loss of the core sample according to the gas content and the residual gas content during core drilling; obtain the light hydrocarbon loss coefficient representing the light hydrocarbon loss of the core sample according to the residual oil content during core drilling and the residual free oil content; Obtain the heavy hydrocarbon content and kerogen content of the second core sample, and obtain the heavy hydrocarbon correction coefficient representing the heavy hydrocarbon loss of the core sample according to the heavy hydrocarbon content and kerogen content; A correction module, which is used to obtain the in-situ oil and gas content of shale oil according to the residual free oil content, light hydrocarbon loss coefficient, free oil loss coefficient during core drilling, pyrolysis hydrocarbon content, heavy hydrocarbon correction coefficient, analytical gas loss coefficient and residual gas content during core drilling.

[0013] An embodiment of the present invention further provides an electronic device, including a memory and a processor; The memory is used to store a computer program; When the processor executes the computer program stored in the memory, it implements the steps of the method for measuring the in-situ oil and gas content in shale oil as described above.

[0014] An embodiment of the present invention also provides a computer-readable storage medium for storing a computer program, which implements the steps of the method for measuring the in-situ oil and gas content in shale oil as described above when executed by a processor.

[0015] An embodiment of the present invention provides a method, device, equipment and medium for measuring the in-situ oil and gas content in shale oil. Compared with the prior art, its beneficial effects are as follows: In the present invention, by performing on-site cryogenic pyrolysis and analytical gas tests on the core samples of pressure-maintained coring and conventional coring, the free oil extraction loss coefficient and the analytical gas loss coefficient are calculated respectively to quantify the loss of hydrocarbons during the experiment. Combining the light hydrocarbon loss coefficient and the heavy hydrocarbon correction coefficient at different placement times, the hydrocarbon loss is further corrected. This process takes into account the differences in hydrocarbon loss amounts under different experimental steps and different experimental methods, and considers the oil and gas loss during the core extraction process, the degree of light hydrocarbon loss and the heavy hydrocarbon correction in the hydrocarbon loss. The in-situ oil content and gas content are respectively restored to obtain the oil content and gas content under in-situ formation conditions, improving the accuracy of the evaluation of shale oiliness and gas content. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall process of a method for measuring the in-situ oil and gas content in shale oil provided by an embodiment of the present invention; Figure 2 It is a comparison schematic diagram of the free oil content S1 obtained by pressure-maintained coring and the residual free oil S1 after core extraction obtained by conventional coring in a method for measuring the in-situ oil and gas content in shale oil provided by an embodiment of the present invention; * COMPARISON SCHEMATIC DIAGRAM Figure 3 It is a schematic diagram of the relationship between the residual free oil content S1 and time after being placed for different times in a method for measuring the in-situ oil and gas content in shale oil provided by an embodiment of the present invention; (x) RELATIONSHIP DIAGRAM OF CHANGE WITH TIME Figure 4 It is a schematic diagram of the proportion of the heavy hydrocarbon content S and the kerogen content S in the pyrolysis hydrocarbon content S2 in a method for measuring the in-situ oil and gas content in shale oil provided by an embodiment of the present invention; 2-1 AND DRY ROOT CONTENT S 2-2 PROPORTION SCHEMATIC DIAGRAM DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0018] See Figure 1 , an embodiment of the present invention provides a method for measuring the in-situ oil and gas content in shale oil, including the following steps: Step 1: Select multiple sampling points according to requirements. For each sampling point, obtain two core samples A and B by pressure-maintained coring. Sample A is frozen and sealed, injected and crushed, and then pyrolyzed to obtain the free oil content S1 of volume mass. Sample B is frozen and sealed, injected and crushed, and then the gas content V of volume content is obtained through desorbed gas testing.

[0019] Step 2: Select multiple sampling points according to requirements. For each sampling point, obtain a total of twelve core samples by conventional coring. Two of the samples are frozen and sealed, injected and crushed, and then pyrolysis experiments and desorbed gas tests are respectively carried out to obtain the residual oil content S1 * , pyrolysis hydrocarbon content S2, and residual gas content V after drill-out * . Another sample is crushed at room temperature and then multi-temperature pyrolysis is carried out to obtain the heavy hydrocarbon content S 2-1 and kerogen content S 2-2 .

[0020] Step 3: Place the remaining nine samples obtained by conventional coring for 1 hour, 2 hours, 4 hours, 8 hours, 24 hours, 48 hours, 96 hours, 192 hours, and 360 hours respectively, and then carry out pyrolysis experiments to obtain the residual free oil S1 (1) , S1 (2) , S1 (4) ……S1 (360) That is .

[0021] Step 4: By comparing the free oil content S1 and the residual oil content S1 after drill-out obtained in Steps 1 and 2 respectively * and the gas content V and the residual gas content V after drill-out * , calculate the free oil drill-out loss coefficient and the desorbed gas loss coefficient .

[0022] The free oil drill-out loss coefficient is expressed as: .

[0023] The desorbed gas loss coefficient Expressed as: .

[0024] Wherein: represents the density of the core sample.

[0025] Step Five: By comparing the residual oil content S1 * obtained in Steps Two and Three respectively (x) and the residual free oil content S1 after being placed for different times,

[0026] calculate the light hydrocarbon loss coefficient after placement for different time periods. : .

[0027] Step Six: Through the heavy hydrocarbon content S 2-1 and the kerogen content S 2-2 obtained in Step Two, calculate the heavy hydrocarbon correction coefficient .

[0028] The heavy hydrocarbon correction coefficient is expressed as: .

[0029] Step Seven: Obtain various coefficients and data through the above steps: Obtain the oil and gas content under the in-situ formation conditions of shale oil Y : .

[0030] Specifically: Step One: Select multiple sampling points according to requirements. For each sampling point, obtain two core samples A and B by pressure-retaining coring. Sample A is frozen and sealed, and after being flushed and crushed, the free oil content S1 of the bulk density is obtained by pyrolysis. Sample B is frozen and sealed, and after being flushed and crushed, the gas content V of the volume content is obtained through analytical gas testing.

[0031] The pressure-retaining coring technology is a method to obtain a core that maintains the integrity of reservoir fluids. By filling the corresponding tool with a sealing liquid before lowering it into the well and continuously sealing the core during the coring drilling process, it is possible to avoid the situation where the gas and light components in the crude oil in the core expand violently and escape due to the decrease in pressure and temperature when the core is taken from the bottom of the well to the surface.

[0032] The free oil content S1 is obtained by pyrolysis after cryogenic sealing, liquid nitrogen injection, pulverization, and then pyrolysis: After obtaining the core sample by pressure coring, it is immediately cryogenically sealed and sent to the corresponding library for cryopreservation for a certain period of time; under liquid nitrogen injection, the core sample is sectioned and hermetically crushed into a powder sample of 200 mesh, and the core powder sample is placed in a RockEval 6 pyrolyzer, and the free oil content S1 is obtained by maintaining a constant temperature of 300 °C for 3 min.

[0033] The gas content V is obtained by analyzing the gas after cryogenic sealing, that is, by the constant temperature analysis - gas volume method: Another core sample obtained by pressure coring at the selected sampling point location is also cryogenically sealed and then sent to the corresponding library for cryopreservation for a certain period of time; under continuous liquid nitrogen injection, the core sample is sectioned, and an analysis device is used to measure and record the analysis gas detection parameters and the corresponding time points at the set analysis temperature to obtain an analysis time - analysis gas volume data table. The analysis gas content can be calculated. After crushing the analyzed core sample, it is analyzed again to obtain the residual gas test record, and the evolved gas content and the lost gas content can be calculated. The sum of the three is the gas content V.

[0034] Step 2: Select multiple sampling points according to requirements. At each sampling point, a total of twelve core samples are obtained by conventional coring. Two of the samples are cryogenically sealed, injected with liquid nitrogen, pulverized, and then subjected to pyrolysis experiments and analysis gas tests respectively to obtain the residual oil content S1 * , the pyrolysis hydrocarbon content S2, and the residual gas content V after drilling * , and another sample is pulverized at room temperature and subjected to multi - temperature - stage pyrolysis to obtain the heavy hydrocarbon content S 2-1 and the kerogen content S 2-2 ; The free hydrocarbon content S1 * and the pyrolysis hydrocarbon content S2 are obtained by pyrolysis after cryogenic sealing, liquid nitrogen injection, and pulverization: After obtaining the core sample by conventional coring, it is immediately cryogenically sealed and sent to the corresponding library for cryopreservation for a certain period of time; under liquid nitrogen injection, the core sample is sectioned and hermetically crushed into a powder sample of 200 mesh, and the core powder sample is placed in a RockEval 6 pyrolyzer, and the free oil content S1 is obtained by maintaining a constant temperature of 300 °C for 3 min. * Then, it is heated to 600 °C at a heating rate of 25 °C per minute to obtain the pyrolysis hydrocarbon content S2.

[0035] The residual gas content V after drilling *Obtained by the desorbed gas test after cryogenic sealing, i.e., the constant temperature desorption - gas volume method: One of the core samples obtained by conventional coring at the selected sampling point is also sealed at ultra - low temperature, and then sent to the corresponding library for cryogenic storage for a certain period of time; under continuous liquid nitrogen injection, the core sample is sectioned, and the desorbed gas detection parameters and corresponding time points are measured and recorded using a desorption device at the set desorption temperature to obtain a desorption time - desorbed gas volume data table. The desorbed gas content can be calculated. After crushing the desorbed core sample, it is desorbed again to obtain the residual gas test record, and the evolved gas content and lost gas content can be calculated. The sum of the three is the gas content V * 。

[0036] The heavy hydrocarbon content S 2-1 and the kerogen content S 2-2 Obtained by multi - temperature - stage pyrolysis experiments: One of the core samples obtained by conventional coring at the selected sampling point is crushed at room temperature, and then the core powder sample is put into a RockEval 6 pyrolyzer. After maintaining a constant temperature of 200 °C for 1 min to obtain the light oil content, it is heated at a rate of 25 °C per minute to 350 °C and maintained at a constant temperature for 1 min to obtain light and medium oils. Then, it is continuously heated at the same rate to 450 °C and maintained at a constant temperature for 1 min to obtain the heavy hydrocarbon content S 2-1 Finally, it is heated to 600 °C at the same rate again to obtain the kerogen content S 2-2 。As Figure 2 shown, it is a comparison of the free oil content S1 obtained by pressure - maintained coring and the residual free oil S1 after drill - out obtained by conventional coring * 。

[0037] Step 3: Place the remaining nine samples of conventional coring for 1 hour, 2 hours, 4 hours, 8 hours, 24 hours, 48 hours, 96 hours, 192 hours, and 360 hours respectively, and then conduct pyrolysis experiments to obtain the residual free oils S1 (1) 、S1 (2) 、S1 (4) ……S1 (360) i.e., 。

[0038] The placement time and the number of core samples can be flexibly selected according to actual needs.

[0039] The residual free oils S1 (1) 、S1 (2) 、S1 (4) ……S1 (360)Obtained by pyrolysis after different placement times: The remaining eight core samples obtained by conventional coring at the selected sampling point positions were crushed after being placed at room temperature for 1 hour, 2 hours, 4 hours, 8 hours, 24 hours, 48 hours, 96 hours, 192 hours, and 360 hours respectively. The core powder samples were put into a RockEval 6 pyrolyzer, and the residual free oil content S1 was obtained by keeping the temperature constant at 300 °C for 3 min (1) 、S1 (2) 、S1 (4) ……S1 (360) That is 。 As Figure 3 shown is the relationship between the residual free oil content S1 (x) and time after different placement times

[0040] Step Four: By comparing the free oil content S1 and the residual oil content S1 obtained from the drill cuttings in Step One and Step Two respectively * as well as the gas content V and the residual gas content V of the drill cuttings * , calculate the free oil loss coefficient of the drill cuttings and the desorbed gas loss coefficient 。

[0041] Step Five: By comparing the residual oil content S1 * obtained from the drill cuttings in Step Two and the residual free oil content S1 after different placement times (x) , calculate the light hydrocarbon loss coefficient after placement in different time periods

[0042] Step Six: Through the heavy hydrocarbon content S 2-1 and kerogen content S 2-2 obtained in Step Two, calculate the heavy hydrocarbon correction coefficient 。 As Figure 4 shown, it is a schematic diagram of the proportion of the heavy hydrocarbon content S 2-1 and kerogen content S 2-2 in the pyrolysis hydrocarbon content S2

[0043] Step Seven: Obtain various coefficients and data through the above steps Obtain the oil and gas content under the in-situ formation conditions of shale oil Y 。

[0044] The method of the present invention includes seven steps: The first step is to conduct on-site pyrolysis experiments and desorbed gas tests on pressure-maintained cores to obtain the free oil content S1 and the gas content V; the second step is to conduct on-site pyrolysis experiments, multi-temperature pyrolysis, and desorbed gas tests on conventional core samples to obtain the residual free oil content S1 * 、pyrolysis hydrocarbon content S 2、 heavy hydrocarbon content S 2-1 、kerogen content S 2-2 and residual gas content V of the drill cuttings* ; In the third step, pyrolysis experiments are carried out on conventional core samples after being placed for different times to obtain the residual free oil content S1 (x) ; In the fourth step, the free oil extraction loss coefficient is calculated respectively and the desorbed gas loss coefficient ; In the fifth step, the light hydrocarbon loss coefficient after placement is calculated ; In the sixth step, according to the obtained heavy hydrocarbon content S 2-1 and the kerogen pyrolysis hydrocarbon content S 2-2 , the heavy hydrocarbon correction coefficient K_heavy is calculated; In the seventh step, the in-situ oil and gas content Y is obtained.

[0045] By conducting on-site cryogenic pyrolysis and desorbed gas tests on pressure-maintained core and conventional core samples, the present invention calculates the free oil extraction loss coefficient and the desorbed gas loss coefficient respectively to quantify the hydrocarbon loss during the experimental process, and combines the light hydrocarbon loss coefficient and the heavy hydrocarbon correction coefficient after being placed for different times to further correct the hydrocarbon loss, and finally restores the oil content and gas content under in-situ formation conditions.

[0046] The present invention restores the in-situ oil content and gas content underground respectively, takes into account the differences in hydrocarbon loss amounts in different experimental steps and experimental methods, avoids the errors caused by using a single fixed coefficient in traditional methods, comprehensively considers the influence of experimental steps, experimental methods and time factors on hydrocarbon loss, significantly improves the accuracy of in-situ oil and gas content evaluation, makes up for the errors caused by hydrocarbon loss in the prior art and the errors in restoration by using a single fixed coefficient method, and at the same time solves the problem of inaccurate evaluation of in-situ oil and gas content in shale oil, provides a scientific basis for the exploration and development of unconventional oil and gas resources, helps to optimize resource evaluation and development plans, has a wide application prospect in unconventional oil and gas fields such as shale oil and tight oil, and can provide important technical support for the energy industry.

[0047] Through innovative experimental designs and data processing methods, the present invention significantly improves the restoration accuracy of in-situ oil content and gas content underground, provides a scientific basis for the exploration and development of unconventional oil and gas resources, and has important theoretical value and practical application significance.

[0048] The above embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A method for measuring the in-situ oil and gas content of shale oil, characterized in that, It includes the following steps: Using the pressure-maintaining coring method to obtain the first core sample of the shale, and obtaining the free oil content and gas content of the first core sample; Using the conventional coring method to obtain the second core sample of the shale, obtaining the residual oil content after drill withdrawal, pyrolysis hydrocarbon content and residual gas content after drill withdrawal of the second core sample, and obtaining the residual free oil content of the second core sample; According to the free oil content and the residual oil content after drill withdrawal, obtaining the free oil loss coefficient after drill withdrawal characterizing the free oil loss of the core sample; according to the gas content and the residual gas content after drill withdrawal, obtaining the desorbed gas loss coefficient characterizing the gas loss of the core sample; according to the residual oil content after drill withdrawal and the residual free oil content, obtaining the light hydrocarbon loss coefficient characterizing the light hydrocarbon loss of the core sample; Obtaining the heavy hydrocarbon content and kerogen content of the second core sample, and obtaining the heavy hydrocarbon correction coefficient characterizing the heavy hydrocarbon loss of the core sample according to the heavy hydrocarbon content and the kerogen content; According to the residual free oil content, light hydrocarbon loss coefficient, free oil loss coefficient after drill withdrawal, pyrolysis hydrocarbon content, heavy hydrocarbon correction coefficient, desorbed gas loss coefficient and residual gas content after drill withdrawal, obtaining the oil and gas content under the in-situ formation conditions of shale oil.

2. The method for measuring the in-situ hydrocarbon content of shale oil according to claim 1, characterized in that, The obtaining of the free oil content and gas content includes: Using pressure-maintaining coring to obtain two core samples, namely Sample A and Sample B; Sealing Sample A of the core sample at ultra-low temperature, performing core sectioning and airtight crushing of the core sample into a powder sample of 200 mesh under liquid nitrogen injection, putting the core powder sample into a pyrolyzer, and obtaining the free oil content S1 at a constant temperature of 300°C for 3 min; Sealing Sample B of the core sample at ultra-low temperature, performing core sectioning of the core sample under continuous liquid nitrogen injection, using an analytical device to measure and record the analytical gas detection parameters and corresponding time points at the set analytical temperature, obtaining the analytical time-analytical gas volume data table, calculating the desorbed gas content, crushing the core sample after analysis and analyzing it again, obtaining the residual gas test record, calculating the gas content and the lost gas content, and the sum of the desorbed gas content, gas content and lost gas content is the gas content V.

3. The method for measuring in-situ oil and gas content of shale oil according to claim 2, characterized in that The obtaining of the residual oil content after drill withdrawal, pyrolysis hydrocarbon content and residual gas content after drill withdrawal includes: Using conventional coring to obtain multiple core samples, and taking two of the core samples as Sample C and Sample D; Seal C core samples at ultra-low temperature. Under liquid nitrogen injection, perform core sectioning and airtight crushing on the core samples to obtain powder samples with a particle size of 200 mesh. Put the core powder samples into a pyrolyzer and maintain a constant temperature of 300 °C for 3 min to obtain the residual oil content S1 of the drill cuttings * ; and then increase the temperature to 600 °C at a heating rate of 25 °C per minute to obtain the pyrolysis hydrocarbon content S2 Seal D core samples at ultra-low temperature, perform core sectioning on the core samples under continuous injection of liquid nitrogen, use an analytical device to measure and record the analytical gas detection parameters and the corresponding time points at the set analytical temperature to obtain an analytical time-analytical gas volume data table, calculate the content of the analytical gas, crush the core samples after analysis and analyze them again to obtain a residual gas test record, calculate the gas content and the lost gas content, and the sum of the analytical gas content, the gas content and the lost gas content is the residual gas content V after drill extraction * .

4. The method for measuring the in-situ hydrocarbon content of shale oil according to claim 3, wherein, The obtaining of the residual free oil content includes: For the core samples remaining after conventional coring, they were respectively placed at room temperature for 1 hour, 2 hours, 4 hours, 8 hours, 24 hours, 48 hours, 96 hours, 192 hours, and 360 hours and then crushed. The core powder samples were put into a pyrolyzer and kept at a constant temperature of 300 °C for 3 min to obtain the residual free oil content S1 corresponding to each time point. (1) , S1 (2) , S1 (4) ……S1 (360) , and the residual free oil content S1 corresponding to each time point (1) , S1 (2) , S1 (4) ……S1 (360) was taken as the residual free oil content .

5. A method for determining the in-situ oil and gas content of shale oil according to claim 4, characterized in that, The free oil extraction loss coefficient is obtained as follows: ； Wherein: S 1 represents the free oil content; S 1 * represents the residual oil content after drill pipe extraction; represents the density of the core sample; The acquisition method of the described analysis gas loss coefficient is as follows: ； Wherein: V represents the gas content; V * represents the residual gas content after drill withdrawal; The light hydrocarbon loss coefficient is obtained as follows: ； Wherein: S 1 * represents the residual oil content after drill withdrawal; represents the residual free oil content corresponding to each time point.

6. The method for measuring the in-situ oil and gas content of shale oil according to claim 5, wherein, The obtaining process of the heavy hydrocarbon correction coefficient includes: Obtain a core sample from conventional coring. After crushing the sample at room temperature, put the core powder sample into a pyrolyzer. Keep it at a constant temperature of 200 °C for 1 min to obtain the light oil content, then increase the temperature at a rate of 25 °C per minute to 350 °C and keep it at a constant temperature for 1 min to obtain the light and medium oil. Continue to increase the temperature at the same rate to 450 °C and keep it at a constant temperature for 1 min to obtain the heavy hydrocarbon content S 2-1 , and finally increase the temperature to 600 °C at the same rate again to obtain the kerogen content S 2-2 ; According to the heavy hydrocarbon content S 2-1 and the kerogen content S 2-2 obtain a heavy hydrocarbon correction coefficient, and the obtaining method of the heavy hydrocarbon correction coefficient is as follows: 。 7. The method for measuring the in-situ oil and gas content of shale oil according to claim 6, wherein The oil and gas content under the in-situ formation conditions of the shale oil Y is obtained by the following method: ； Wherein: represents the residual free oil content; represents the light hydrocarbon loss coefficient; represents the free oil loss coefficient during drill extraction; represents the pyrolysis hydrocarbon content; represents the heavy hydrocarbon correction coefficient; represents the desorbed gas loss coefficient; V * represents the residual gas content during drill extraction.

8. An in-situ oil and gas content measuring device for shale oil, characterized in that It includes: An experimental module for using the pressure-maintaining coring method to obtain the first core sample of the shale, and obtaining the free oil content and gas content of the first core sample; Using the conventional coring method to obtain the second core sample of the shale, obtaining the residual oil content after drill withdrawal, pyrolysis hydrocarbon content and residual gas content after drill withdrawal of the second core sample, and obtaining the residual free oil content of the second core sample; A hydrocarbon loss module for obtaining the free oil loss coefficient after drill withdrawal characterizing the free oil loss of the core sample according to the free oil content and the residual oil content after drill withdrawal; obtaining the desorbed gas loss coefficient characterizing the gas loss of the core sample according to the gas content and the residual gas content after drill withdrawal; obtaining the light hydrocarbon loss coefficient characterizing the light hydrocarbon loss of the core sample according to the residual oil content after drill withdrawal and the residual free oil content; Obtain the heavy hydrocarbon content and kerogen content of the second core sample, and based on the heavy hydrocarbon content and kerogen content, obtain a heavy hydrocarbon correction coefficient that characterizes the heavy hydrocarbon loss of the core sample; A correction module, configured to obtain the oil and gas content under in-situ formation conditions of shale oil according to the residual free oil content, light hydrocarbon loss coefficient, free oil loss coefficient during drilling extraction, pyrolysis hydrocarbon content, heavy hydrocarbon correction coefficient, analytical gas loss coefficient, and residual gas content during drilling extraction.

9. An electronic device, characterized in that, Including: A memory and a processor; The memory is used to store a computer program; When the processor executes the computer program stored in the memory, it implements the steps of a method for determining the in-situ oil and gas content of shale oil according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, For storing a computer program, when the computer program is executed by a processor, it implements the steps of a method for determining the in-situ oil and gas content of shale oil according to any one of claims 1 to 7.

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