A method and system for quantitatively calculating original oil reserves of an ancient oil reservoir

Abstract

The application discloses a kind of ancient oil reservoir original oil reserves quantitative calculation method and system, wherein, the method includes: presetting geological model, establishing ancient oil reservoir original oil reserves calculation model;Obtain the calculation parameter of ancient oil reservoir original oil reserves;The calculation parameter is substituted into the calculation model, and the original oil reserves of ancient oil reservoir are obtained.The application obtains the oil and gas density, asphalt density, crude oil volume coefficient, crude oil cracking rate, methane compression factor based on experimental measurement in the study of dynamic accumulation process of accumulation geology, in combination with known carbonate rock gas reservoir area, reservoir thickness, gas saturation, natural gas reservoir temperature, pressure and other parameters, according to the calculation method of the application, the geological reserves of ancient oil reservoir are quantitatively calculated, the reliability and accuracy of the calculation result of ancient oil reservoir original oil reserves are improved, and the practicality is stronger.

Description

Technical Field

[0001] This invention belongs to the field of petroleum geological exploration, and specifically relates to a quantitative calculation method and system for the original petroleum reserves of ancient oil reservoirs. Background Technology

[0002] Hydrocarbon reservoir geology is the core of petroleum geology, a branch of petroleum geology that studies the formation and distribution patterns of oil and gas reservoirs. Its research content includes the basic elements or conditions of oil and gas reservoir formation, reservoir chronology, reservoir geochemistry, reservoir dynamics, and the laws governing the formation and distribution of oil and gas reservoirs. It is an independent branch of petroleum geology, alongside petroleum structural geology, organic geochemistry, reservoir geology, and development geology. The research content of hydrocarbon reservoir geology includes static reservoir-forming elements, dynamic reservoir-forming processes, interactions, and the final reservoir-forming results, involving all aspects affecting the formation and distribution of oil and gas reservoirs, such as generation, migration, accumulation, and preservation. The petroleum geological reserves of ancient reservoirs are a very important parameter in hydrocarbon reservoir research, significantly contributing to the study of ancient reservoir scale, hydrocarbon generation potential, and resource potential, and providing important guidance for zonal evaluation and the identification of favorable targets. The volumetric method is primarily used to estimate the petroleum geological reserves of ancient reservoirs.

[0003] Determining the area of ​​ancient oil reservoirs is a challenge. Traditional methods mainly include two approaches: one is to determine the area based on the distribution area of ​​bitumen; the other is to determine the area based on the area of ​​ancient traps. The method based on bitumen distribution has two drawbacks: first, it requires drilling data, which is unsuitable for areas lacking such data; second, identifying the area of ​​ancient crude oil based on residual bitumen in the current reservoir requires certain conditions, as the structural morphology of the current gas field differs significantly from that of the ancient crude oil accumulation site. Therefore, it is essential to clarify whether the distribution of solid bitumen was affected by tectonic deformation, i.e., whether crude oil cracking was completed before tectonic deformation. The method based on the area of ​​ancient traps has limitations. Since the reservoir may not fill the entire trap, the ancient trap represents the largest ancient oil reservoir area, not necessarily the actual area of ​​the ancient oil reservoir. Summary of the Invention

[0004] To address the above problems, this invention discloses a quantitative calculation method for the original oil reserves of ancient oil reservoirs, the method comprising:

[0005] Pre-set a geological model and establish a model for calculating the original oil reserves of ancient oil reservoirs;

[0006] Calculation parameters for obtaining the original oil reserves of ancient oil reservoirs;

[0007] Substitute the calculation parameters into the calculation model to obtain the original oil reserves of the ancient oil reservoir.

[0008] Furthermore, the steps for establishing a calculation model for the original oil reserves of ancient oil reservoirs using the preset geological model specifically include:

[0009] The geological model is presupposed as follows: the natural gas reservoir generated after crude oil cracking is located in the ancient oil reservoir, and the cracking process generates little or no gas from kerogen; the reservoir thickness remains unchanged before and after crude oil cracking, and the changes in reservoir properties are caused by bitumen filling; the preservation conditions are good, and the loss of natural gas reservoir is small.

[0010] The established model for calculating the original oil reserves of ancient oil reservoirs is as follows:

[0011]

[0012] Where Mo is the mass of crude oil; Ag is the gas-bearing area of ​​the natural gas reservoir; h is the average thickness of the natural gas reservoir; and Soi is the oil saturation of the ancient oil reservoir. X is the porosity of the natural gas reservoir; Xm is the crude oil cracking rate, representing the percentage of total mass of natural gas produced relative to the mass of crude oil; Boi is the crude oil volume coefficient; ρg is the density of natural gas under standard surface conditions, which is 0.667 kg / m³. 3 ρo is the density of crude oil in the ancient oil reservoir under standard surface conditions; ρb is the density of bitumen; Zi is the original gas deviation coefficient; Psc is the standard surface pressure, which is 0.101 MPa; T is the formation temperature; Pi is the original formation pressure of the natural gas reservoir; Tsc is the standard surface temperature, which is 293 K.

[0013] Furthermore, the step of obtaining the calculation parameters for the original oil reserves of the ancient oil reservoir specifically includes:

[0014] To obtain information on the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of natural gas reservoirs;

[0015] Determine the density of crude oil of the same type as the original oil in the ancient oil reservoir under surface conditions;

[0016] Calculate the volume factor of crude oil based on the burial depth of ancient oil reservoirs;

[0017] Determine the density of asphalt and the mass of asphalt in a hydrocarbon generation simulation experiment, and calculate the crude oil cracking rate;

[0018] Determine the original gas deviation coefficient of the natural gas reservoir.

[0019] Furthermore, the steps for obtaining the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of the natural gas reservoir specifically include:

[0020] Based on the natural gas reservoir reserve report and production test data, the reservoir area Ag, reservoir thickness h, gas saturation Soi, and porosity were obtained. Formation temperature T and original formation pressure Pi.

[0021] Furthermore, the step of determining the density of crude oil of the same type as the original oil in the ancient reservoir under surface conditions specifically includes:

[0022] Based on the type of source rock in the natural gas reservoir, crude oil generated from the same type of source rock was selected as a reference object, and the density ρo of the crude oil was measured under standard ground conditions.

[0023] Furthermore, the step of calculating the volume factor of crude oil based on the burial depth of the ancient oil reservoir specifically includes:

[0024] The crude oil volume factor Boi is defined as the ratio of the volume of crude oil underground (Vf) to the volume of crude oil after degassing at the surface (Vs).

[0025] The expression for the crude oil volume coefficient Boi, obtained from the Standing empirical formula, is as follows:

[0026] Boi = 0.972 + 1.1213 × 10 -2 F 1.175 ;

[0027]

[0028] Where Rs represents the volume ratio of dissolved gas to oil, Ro is the relative density of the degassed crude oil at the surface, and Rg is the relative density of the separator gas, which is 1.0 kg / m³. 3 T represents the formation temperature at the depth of the ancient oil reservoir, determined based on its burial history.

[0029] Furthermore, the steps of determining the density of asphalt and the mass of asphalt in the hydrocarbon generation simulation experiment, and calculating the crude oil cracking rate specifically include:

[0030] A crude oil sample weighing m1 was injected into a gold tube to conduct a thermal simulation experiment of hydrocarbon generation in the gold tube.

[0031] After the crude oil is completely cracked, the residual sample is taken out and weighed as m2. Then the amount of crude oil cracked is m1-m2. Calculate the cracking rate Xm=(m1-m2) / m1.

[0032] Furthermore, the step of determining the original gas deviation coefficient of the natural gas reservoir specifically includes:

[0033] The volume of natural gas was measured under the actual temperature and pressure conditions of the natural gas reservoir.

[0034] The volume of natural gas is measured under standard ground conditions, and the original gas deviation coefficient Zi of the natural gas reservoir is calculated based on the gas state equation.

[0035] Furthermore, the ground standard conditions are a temperature of 293 K and a pressure of 0.101 MPa.

[0036] On another aspect, the present invention also discloses a quantitative calculation system for the original oil reserves of ancient oil reservoirs, the system comprising:

[0037] The acquisition unit is used to acquire calculation parameters of the original oil reserves of ancient oil reservoirs and transmit the calculation parameters to the calculation unit;

[0038] The calculation unit is used to preset the geological model, establish the calculation model of the original oil reserves of the ancient oil reservoir, and also to receive the calculation parameters sent by the acquisition unit and obtain the original oil reserves of the ancient oil reservoir according to the calculation model.

[0039] Furthermore, the specific steps of the calculation unit executing a preset geological model to establish a calculation model for the original oil reserves of the ancient oil reservoir include:

[0040] The geological model is presupposed as follows: the natural gas reservoir generated after crude oil cracking is located in the ancient oil reservoir, and the cracking process generates little or no gas from kerogen; the reservoir thickness remains unchanged before and after crude oil cracking, and the changes in reservoir properties are caused by bitumen filling; the preservation conditions are good, and the loss of natural gas reservoir is small.

[0041] The established model for calculating the original oil reserves of ancient oil reservoirs is as follows:

[0042]

[0043] Where Mo is the mass of crude oil; Ag is the gas-bearing area of ​​the natural gas reservoir; h is the average thickness of the natural gas reservoir; and Soi is the oil saturation of the ancient oil reservoir. X is the porosity of the natural gas reservoir; Xm is the crude oil cracking rate, representing the percentage of total mass of natural gas produced relative to the mass of crude oil; Boi is the crude oil volume coefficient; ρg is the density of natural gas under standard surface conditions, which is 0.667 kg / m³. 3 ρo is the density of crude oil in the ancient oil reservoir under standard surface conditions; ρb is the density of bitumen; Zi is the original gas deviation coefficient; Psc is the standard surface pressure, which is 0.101 MPa; T is the formation temperature; Pi is the original formation pressure of the natural gas reservoir; Tsc is the standard surface temperature, which is 293 K.

[0044] Furthermore, the step of the acquisition unit performing the calculation parameters for obtaining the original oil reserves of the ancient oil reservoir specifically includes:

[0045] To obtain information on the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of natural gas reservoirs;

[0046] Determine the density of crude oil of the same type as the original oil in the ancient oil reservoir under surface conditions;

[0047] Calculate the volume factor of crude oil based on the burial depth of ancient oil reservoirs;

[0048] Determine the density of asphalt and the mass of asphalt in a hydrocarbon generation simulation experiment, and calculate the crude oil cracking rate;

[0049] Determine the original gas deviation coefficient of the natural gas reservoir.

[0050] Furthermore, the steps of the acquisition unit to acquire the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of the natural gas reservoir specifically include:

[0051] Based on the natural gas reservoir reserve report and production test data, the reservoir area Ag, reservoir thickness h, gas saturation Soi, and porosity were obtained. Formation temperature T and original formation pressure Pi.

[0052] Furthermore, the step of the acquisition unit performing the determination of the density of crude oil of the same type as the original oil in the ancient reservoir under surface conditions specifically includes:

[0053] Based on the type of source rock in the natural gas reservoir, crude oil generated from the same type of source rock was selected as a reference object, and the density ρo of the crude oil was measured under standard ground conditions.

[0054] Furthermore, the step of the acquisition unit calculating the volume factor of crude oil based on the burial depth of the ancient oil reservoir specifically includes:

[0055] The crude oil volume factor Boi is defined as the ratio of the volume of crude oil underground (Vf) to the volume of crude oil after degassing at the surface (Vs).

[0056] The expression for the crude oil volume coefficient Boi, obtained from the Standing empirical formula, is as follows:

[0057] Boi = 0.972 + 1.1213 × 10 -2 F 1.175 ;

[0058]

[0059] Where Rs represents the volume ratio of dissolved gas to oil, Ro is the relative density of the degassed crude oil at the surface, and Rg is the relative density of the separator gas, which is 1.0 kg / m³. 3 T represents the formation temperature at the depth of the ancient oil reservoir, determined based on its burial history.

[0060] Furthermore, the steps of the acquisition unit in measuring the density of asphalt and the mass of asphalt in the hydrocarbon generation simulation experiment, and calculating the crude oil cracking rate, specifically include:

[0061] A crude oil sample weighing m1 was injected into a gold tube to conduct a thermal simulation experiment of hydrocarbon generation in the gold tube.

[0062] After the crude oil is completely cracked, the residual sample is taken out and weighed as m2. Then the amount of crude oil cracked is m1-m2. Calculate the cracking rate Xm=(m1-m2) / m1.

[0063] Furthermore, the step of the acquisition unit performing the determination of the original gas deviation coefficient of the natural gas reservoir specifically includes:

[0064] The volume of natural gas is measured under constant temperature and pressure conditions within the natural gas reservoir.

[0065] The volume of natural gas is measured under standard ground conditions, and the original gas deviation coefficient Zi of the natural gas reservoir is calculated based on the gas state equation.

[0066] This invention addresses the shortcomings and deficiencies of existing technologies for determining the geological reserves of ancient oil reservoirs by providing a rationally designed and quantitative calculation method for calculating the original oil reserves of closed carbonate rock fractured ancient oil reservoirs. In studying the dynamic process of reservoir formation geology, this method quantitatively calculates the geological reserves of ancient oil reservoirs based on experimentally measured oil and gas density, bitumen density, crude oil volume factor, crude oil cracking rate, and methane compressibility factor; combined with known parameters such as carbonate rock natural gas reservoir area, reservoir thickness, gas saturation, natural gas reservoir temperature, and pressure. This improves the reliability and accuracy of the results and enhances their practicality.

[0067] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0068] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0069] Figure 1 A schematic diagram illustrating the quantitative calculation process for the original oil reserves of an ancient oil reservoir according to an embodiment of the present invention is shown. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0071] This invention proposes a quantitative calculation method for the original petroleum reserves of ancient oil reservoirs, the method comprising:

[0072] Step 1: Pre-set geological model and establish a calculation model for the original oil reserves of ancient oil reservoirs;

[0073] Step 2: Obtain the calculation parameters for the original oil reserves of the ancient oil reservoir;

[0074] Step 3: Substitute the calculation parameters into the calculation model to obtain the original oil reserves of the ancient oil reservoir.

[0075] The geological model set in step 1 is as follows:

[0076] (1) The natural gas reservoirs generated after crude oil cracking are located in ancient oil reservoirs, and the cracking process generates little or no gas from kerogen.

[0077] (2) The reservoir thickness remains unchanged before and after crude oil cracking, and the changes in reservoir properties are caused by asphalt filling;

[0078] (3) The preservation conditions are good, the loss of natural gas reservoir is small, and the gas saturation is equal to the oil saturation.

[0079] In one embodiment of the present invention, the step 1 of establishing the original oil reserve calculation model of the ancient oil reservoir specifically includes the following process:

[0080] Step 1.1 Following the requirements of the "Calculation Method for Controlled Reserves of Oil and Gas (Q / SY 179-2006)," the geological reserves are calculated using the volumetric method. The calculation formula is:

[0081]

[0082]

[0083] Bgi=(Psc×Zi×T) / (Pi×Tsc) (3)

[0084] In the formula: G represents the geological reserves of natural gas, in m³. 3 Ag represents the gas-bearing area, in m². 2 N represents the geological reserves of petroleum, in cubic meters (m³). 3 Ao represents the oil-bearing area, in m².2 h represents the effective thickness, in meters (m). Effective porosity; Sgi is the original gas saturation; Soi is the original oil saturation; Bgi is the original natural gas volume factor; Boi is the original oil volume factor; Psc is the surface standard pressure, which is 0.101 MPa; Zi is the original gas deviation factor; T is the formation temperature, in K; Pi is the natural gas reservoir formation pressure, in MPa; Tsc is the surface standard temperature, which is 293 K.

[0085] Because the geological model indicates a relatively small loss of gas reserves, the area of ​​the natural gas reservoir must be no smaller than the original oil reservoir area. Therefore, the current gas-bearing area Ag (in m²) can be determined. 2 It consists of two parts: one part is the area Ao of the original reservoir (in m²). 2 Ao is an unknown quantity, which is the parameter to be determined. The other part is the area of ​​natural gas expansion: Ag-Ao. The parameters in the above formula corresponding to these two parts are only the effective porosity. They are different. Within the original reservoir, the porosity is smaller due to the filling of bitumen. Let the residual porosity after reservoir pyrolysis be... The porosity within the expanded area of ​​natural gas is equal to the original porosity.

[0086] According to formula (1), the geological reserves of natural gas within the current gas-bearing area are:

[0087]

[0088] Step 1.2: Based on the density ρg of natural gas under standard surface conditions (in kg / m³), the mass of natural gas in the reservoir is:

[0089]

[0090] Where Mg represents the mass of natural gas, in kg.

[0091] Step 1.3: Based on the cracking rate and the law of conservation of mass, convert the mass of natural gas into the mass of crude oil before cracking:

[0092] Mo=Mg / Xm (6)

[0093] Substituting formula (5) into formula (6), we obtain the expression for crude oil quality as follows:

[0094]

[0095] Where Mo represents the mass of crude oil, in kg.

[0096] Step 1.4: According to formula (2), the geological reserves of the original oil reservoir are:

[0097]

[0098] In the formula, Soi is the original oil saturation. For simplification, Soi = Sgi.

[0099] Step 1.5: After the crude oil in the reservoir is cracked, the remaining total mass is:

[0100]

[0101] Ms represents the residual weight of the crude oil after cracking, in kg; V represents the total reservoir volume, in m³. 3 .

[0102] The total weight of bitumen in the reservoir pores is:

[0103]

[0104] Mb is the total weight of bitumen in the reservoir pores, in kg; V is the total volume of the reservoir, in m³. 3 ρb is the density of asphalt, in kg / m³. 3 .

[0105] According to the law of conservation of mass, the weight of the bitumen in the pores is equal to the residual weight of the crude oil after cracking, that is:

[0106]

[0107] After sorting, we get:

[0108]

[0109] Step 1.6: Solve equations (7) and (8) simultaneously, then...

[0110]

[0111] Rearranging formula (13), we get:

[0112]

[0113] Substituting formulas (12) and (3) into formula (14) and rearranging, we get:

[0114]

[0115] Step 1.7: According to formula (12), we can obtain...

[0116]

[0117] Step 1.8: Substitute formulas (15) and (16) into formula (8) to obtain the original oil reserves calculation model of the ancient oil reservoir described in Step 1:

[0118]

[0119] Where Mo represents the mass of crude oil, in kg.

[0120] In one embodiment of the present invention, step 2, obtaining the calculation parameters for the original oil reserves of the ancient oil reservoir, includes:

[0121] Step 2.1: Obtain the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of the natural gas reservoir;

[0122] Specifically, based on the natural gas reservoir reserve report and production test data, the area Ag, reservoir thickness h, gas saturation Soi, and porosity of the natural gas reservoir are obtained. Formation temperature T and original formation pressure Pi.

[0123] Step 2.2: Determine the density of crude oil of the same type as the original oil in the ancient reservoir under surface conditions;

[0124] Specifically, based on the type of source rock in the natural gas reservoir, crude oil generated from the same type of source rock is selected as a reference object, and the density ρo of the crude oil is measured under standard ground conditions.

[0125] Step 2.3: Calculate the volume factor of crude oil based on the burial depth of the ancient oil reservoir;

[0126] Specifically, the crude oil volume factor Boi is defined as the ratio of the volume of crude oil underground (Vf) to the volume of crude oil after degassing at the surface (Vs).

[0127] The expression for the crude oil volume coefficient Boi, obtained from the Standing empirical formula, is as follows:

[0128] Boi = 0.972 + 1.1213 × 10 -2 F 1.175 ;

[0129]

[0130] Where Rs represents the volume ratio of dissolved gas to oil, Ro is the relative density of the degassed crude oil at the surface, and Rg is the relative density of the gas in the separator (taken as air density 1.0 kg / m³). 3 T represents the formation temperature at the depth of the ancient oil reservoir determined based on its burial history.

[0131] Step 2.4: Determine the density of asphalt and the mass of asphalt in the hydrocarbon generation simulation experiment, and calculate the crude oil cracking rate;

[0132] Specifically, a crude oil weighing m1 was drawn into a gold tube using a glass syringe to conduct a thermal simulation experiment of hydrocarbon generation in the gold tube.

[0133] The experimental apparatus was gradually heated to its limit temperature. After the crude oil was completely cracked, the residual sample was removed and weighed as m2. The amount of crude oil cracked was then m1-m2. The cracking rate Xm was calculated as Xm = (m1-m2) / m1.

[0134] Step 2.5: Determine the original gas deviation coefficient of the natural gas reservoir.

[0135] Using a high-pressure physical property (PVT) cylinder, the volume of natural gas was measured under the temperature and pressure conditions of an actual natural gas reservoir. The volume of the natural gas was also measured under standard surface conditions. The original gas deviation coefficient Zi of the natural gas reservoir was calculated based on the gas's equation of state. The standard surface conditions were a temperature of 293 K and a pressure of 0.101 MPa.

[0136] In one embodiment of the present invention, the present invention also provides a quantitative calculation system for the original oil reserves of ancient oil reservoirs, the system comprising:

[0137] The acquisition unit is used to acquire calculation parameters of the original oil reserves of ancient oil reservoirs and transmit the calculation parameters to the calculation unit;

[0138] The calculation unit is used to establish a calculation model for the original oil reserves of the ancient oil reservoir based on the geological model, and is also used to receive calculation parameters sent by the acquisition unit and obtain the original oil reserves of the ancient oil reservoir according to the calculation model.

[0139] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for quantitatively calculating the original petroleum reserves of an ancient oil reservoir, characterized in that, The method includes: Pre-set a geological model and establish a model for calculating the original oil reserves of ancient oil reservoirs; The specific steps for establishing a calculation model for the original oil reserves of an ancient oil reservoir include: The geological model is presupposed as follows: the natural gas reservoir generated after crude oil cracking is located in the ancient oil reservoir, and the cracking process generates little or no gas from kerogen; the reservoir thickness remains unchanged before and after crude oil cracking, and the changes in reservoir properties are caused by bitumen filling; the preservation conditions are good, and the loss of natural gas reservoir is small. The established model for calculating the original oil reserves of ancient oil reservoirs is as follows: ； Where Mo is the mass of crude oil; Ag is the gas-bearing area of ​​the natural gas reservoir; h is the average thickness of the natural gas reservoir; and Soi is the oil saturation of the ancient oil reservoir. o represents the porosity of the natural gas reservoir; Xm represents the crude oil cracking rate, indicating the percentage of the total mass of natural gas produced relative to the mass of crude oil; Boi represents the crude oil volume coefficient; ρg represents the density of natural gas under standard surface conditions; ρo represents the density of crude oil from the ancient oil reservoir under standard surface conditions; ρb represents the density of bitumen; Zi represents the original gas deviation coefficient; Psc represents the standard surface pressure; T represents the formation temperature; Pi represents the original formation pressure of the natural gas reservoir; Tsc represents the standard surface temperature. Calculation parameters for obtaining the original oil reserves of ancient oil reservoirs; Substitute the calculation parameters into the calculation model to obtain the original oil reserves of the ancient oil reservoir.

2. The quantitative calculation method according to claim 1, characterized in that, The specific steps for obtaining the calculation parameters for the original oil reserves of ancient oil reservoirs include: To obtain information on the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of natural gas reservoirs; Determine the density of crude oil of the same type as the original oil in the ancient oil reservoir under surface conditions; Calculate the volume factor of crude oil based on the burial depth of ancient oil reservoirs; Determine the density of asphalt and the mass of asphalt in a hydrocarbon generation simulation experiment, and calculate the crude oil cracking rate; Determine the original gas deviation coefficient of the natural gas reservoir.

3. The quantitative calculation method according to claim 2, characterized in that, The steps for obtaining the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of the natural gas reservoir specifically include: Based on the natural gas reservoir reserve report and production test data, the reservoir area Ag, reservoir thickness h, gas saturation Soi, and porosity were obtained. o, formation temperature T, and original formation pressure Pi.

4. The quantitative calculation method according to claim 2, characterized in that, The specific steps for determining the density of crude oil of the same type as that of the original oil in the ancient reservoir under surface conditions include: Based on the type of source rock in the natural gas reservoir, crude oil generated from the same type of source rock is selected as a reference object, and the density of the crude oil of the reference object under standard ground conditions is measured as the density ρo of the ancient oil reservoir crude oil.

5. The quantitative calculation method according to claim 2, characterized in that, The steps for calculating the volume factor of crude oil based on the burial depth of ancient oil reservoirs specifically include: The crude oil volume factor Boi is defined as the ratio of the volume of crude oil underground (Vf) to the volume of crude oil after degassing at the surface (Vs). The expression for the crude oil volume coefficient Boi, obtained from the Standing empirical formula, is as follows: ； F=0.1404R s ( ) 0.5 +5.625×10 -2 T+1; Where Rs represents the volume ratio of dissolved gas to oil. Ro The relative density of the degassed crude oil at ground level; Rg The relative density of the gas in the separator is . T represents the formation temperature at the depth of the ancient oil reservoir, determined based on its burial history.

6. The quantitative calculation method according to claim 2, characterized in that, The steps for determining the density of asphalt and the mass of asphalt in the hydrocarbon generation simulation experiment, and calculating the crude oil cracking rate, specifically include: A crude oil sample weighing m1 was injected into a gold tube to conduct a thermal simulation experiment of hydrocarbon generation in the gold tube. After the crude oil is completely cracked, the residual sample is taken out and weighed as m2. Then the amount of crude oil cracked is m1-m2. Calculate the cracking rate Xm=(m1-m2) / m1.

7. The quantitative calculation method according to claim 2, characterized in that, The steps for determining the original gas deviation coefficient of a natural gas reservoir specifically include: The volume of natural gas was measured under the actual temperature and pressure conditions of the natural gas reservoir. The volume of natural gas is measured under standard ground conditions, and the original gas deviation coefficient Zi of the natural gas reservoir is calculated based on the gas state equation.

8. The quantitative calculation method according to claim 4 or 7, characterized in that, The ground standard conditions are a temperature of 293 K and a pressure of 0.101 MPa.

9. A quantitative calculation system for the original petroleum reserves of an ancient oil reservoir, characterized in that, The system includes: The acquisition unit is used to acquire calculation parameters of the original oil reserves of ancient oil reservoirs and transmit the calculation parameters to the calculation unit; The calculation unit is used to preset the geological model, establish the calculation model of the original oil reserves of the ancient oil reservoir, and also to receive the calculation parameters sent by the acquisition unit and obtain the original oil reserves of the ancient oil reservoir according to the calculation model. The specific steps for establishing a calculation model for the original oil reserves of an ancient oil reservoir include: The geological model is presupposed as follows: the natural gas reservoir generated after crude oil cracking is located in the ancient oil reservoir, and the cracking process generates little or no gas from kerogen; the reservoir thickness remains unchanged before and after crude oil cracking, and the changes in reservoir properties are caused by bitumen filling; the preservation conditions are good, and the loss of natural gas reservoir is small. The established model for calculating the original oil reserves of ancient oil reservoirs is as follows: ； Where Mo is the mass of crude oil; Ag is the gas-bearing area of ​​the natural gas reservoir; h is the average thickness of the natural gas reservoir; and Soi is the oil saturation of the ancient oil reservoir. o represents the porosity of the natural gas reservoir; Xm represents the crude oil cracking rate, indicating the percentage of the total mass of natural gas produced relative to the mass of crude oil; Boi represents the crude oil volume coefficient; ρg represents the density of natural gas under standard surface conditions; ρo represents the density of crude oil from the ancient oil reservoir under standard surface conditions; ρb represents the density of bitumen; Zi represents the original gas deviation coefficient; Psc represents the standard surface pressure; T represents the formation temperature; Pi represents the original formation pressure of the natural gas reservoir; and Tsc represents the standard surface temperature.

10. The quantitative calculation system according to claim 9, characterized in that, The specific steps of the acquisition unit in performing the calculation parameters for obtaining the original oil reserves of the ancient oil reservoir include: To obtain information on the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of natural gas reservoirs; Determine the density of crude oil of the same type as the original oil in the ancient oil reservoir under surface conditions; Calculate the volume factor of crude oil based on the burial depth of ancient oil reservoirs; Determine the density of asphalt and the mass of asphalt in a hydrocarbon generation simulation experiment, and calculate the crude oil cracking rate; Determine the original gas deviation coefficient of the natural gas reservoir.

11. The quantitative calculation system according to claim 10, characterized in that, The steps performed by the acquisition unit to acquire the area, reservoir thickness, gas saturation, porosity, temperature, and original formation pressure of the natural gas reservoir specifically include: Based on the natural gas reservoir reserve report and production test data, the reservoir area Ag, reservoir thickness h, gas saturation Soi, and porosity were obtained. o, formation temperature T, and original formation pressure Pi.

12. The quantitative calculation system according to claim 10, characterized in that, The specific steps of the acquisition unit in performing the determination of the density of crude oil of the same type as the original oil in the ancient reservoir under surface conditions include: Based on the type of source rock in the natural gas reservoir, crude oil generated from the same type of source rock was selected as a reference object, and the density ρo of the crude oil was measured under standard ground conditions.

13. The quantitative calculation system according to claim 10, characterized in that, The step of the acquisition unit calculating the volume factor of crude oil based on the burial depth of the ancient oil reservoir specifically includes: The crude oil volume factor Boi is defined as the ratio of the volume of crude oil underground (Vf) to the volume of crude oil after degassing at the surface (Vs). The expression for the crude oil volume coefficient Boi, obtained from the Standing empirical formula, is as follows: ； F=0.1404R s ( ) 0.5 +5.625×10 -2 T+1; Where Rs represents the volume ratio of dissolved gas to oil, Ro is the relative density of the degassed crude oil at the surface, and Rg is the relative density of the gas in the separator. T represents the formation temperature at the depth of the ancient oil reservoir, determined based on its burial history.

14. The quantitative calculation system according to claim 10, characterized in that, The steps of the acquisition unit to measure the density of asphalt and the mass of asphalt in the hydrocarbon generation simulation experiment, and to calculate the crude oil cracking rate, specifically include: A crude oil sample weighing m1 was injected into a gold tube to conduct a thermal simulation experiment of hydrocarbon generation in the gold tube. After the crude oil is completely cracked, the residual sample is taken out and weighed as m2. Then the amount of crude oil cracked is m1-m2. Calculate the cracking rate Xm=(m1-m2) / m1.

15. The quantitative calculation system according to claim 10, characterized in that, The specific steps of the acquisition unit in determining the original gas deviation coefficient of the natural gas reservoir include: The volume of natural gas is measured under constant temperature and pressure conditions within the natural gas reservoir. The volume of natural gas is measured under standard ground conditions, and the original gas deviation coefficient Zi of the natural gas reservoir is calculated based on the gas state equation.

Images