Reservoir evaluation method based on aftereffect released gas volume

Abstract

The application discloses a reservoir evaluation method based on aftereffect gas release amount, relates to the technical field of drilling geology evaluation, and is based on mud logging time data, calculates aftereffect gas amount and aftereffect gas efficiency of aftereffect through standardized processing of full hydrocarbon gas measurement of the aftereffect section, establishes an aftereffect gas efficiency function by adopting a Gaussian function mode fitting according to the change characteristics of aftereffect intensity with reservoir opening time, integrates to obtain total aftereffect gas release amount, fits a correlation function of the total aftereffect gas release amount of the tested section of the tested oil well after standardization of drilling fluid density and the tested open flow capacity of the section, establishes reservoir evaluation standards of the aftereffect gas release amount in combination with reservoir evaluation standards of the open flow capacity, forms the reservoir evaluation method, and solves the problem that the gas measurement parameter correction technology in the prior art, which is mainly dominated by drilling time, discharge capacity, drill bit size and other engineering parameters, is obviously unsuitable and is difficult to improve the reservoir responsiveness of the gas measurement parameters.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of geologic evaluation while drilling, and particularly relates to a reservoir evaluation method based on aftereffect released gas volume. BACKGROUND

[0002] At present, reservoir evaluation while drilling mainly takes the gas logging, drilling time and other logging parameters with certain responsiveness to the reservoir as the main basis, combines the influences of the drilling pressure, rotating speed, displacement and other engineering parameters on the responsive parameters, corrects according to the curve shape change or uses the reservoir evaluation technology based on these parameters to evaluate, which is widely applied and has good effect.

[0003] However, with the wide application of new drilling technologies such as fine pressure control, liquid-gas separator and oil-based drilling fluid in recent years, the key parameter of reservoir evaluation while drilling, i.e. gas logging parameter, is seriously affected. The gas logging parameter value is obviously lower than that of the old well without using these new drilling technologies, and is completely unmatched with the test production, which leads to the obvious deterioration of the application effect of the existing reservoir evaluation while drilling method, especially the method taking the gas logging parameter value as the core. Moreover, due to the changes of the process characteristics and flow, the existing gas logging parameter correction technology mainly based on the drilling time, displacement and drill bit size is obviously not applicable, and it is difficult to improve the reservoir responsiveness of the gas logging parameter.

[0004] The "failure" of the gas logging parameter makes it difficult to find a parameter with good reservoir responsiveness in the existing logging parameters, which is undoubtedly a great obstacle to the development of reservoir evaluation while drilling technology. Therefore, it is necessary to innovate the logging responsive parameters and research new reservoir evaluation while drilling method. SUMMARY

[0005] The present application aims to solve the above problems, and provides a reservoir evaluation method based on aftereffect released gas volume, which is a new reservoir evaluation while drilling method based on logging time data.

[0006] The present application is implemented by the following technical scheme:

[0007] The reservoir evaluation method based on aftereffect released gas volume comprises the following steps:

[0008] a. Collect the logging, well logging data and test oil data of the specific layer series of the tested well in the study area, and screen out the aftereffect corresponding to the gas logging display in the test section;

[0009] b. Extract the total hydrocarbon data corresponding to the aftereffect according to the aftereffect time;

[0010] c. Standardize the total hydrocarbon data of the extracted aftereffect in terms of the base value, time interval and displacement;

[0011] d. According to the time from the beginning to the end of the aftereffect, the aftereffect gas amount is accumulated by using the standard total hydrocarbon, and the aftereffect gas efficiency is calculated by combining the static time;

[0012] e. The aftereffect gas efficiencies of the corresponding multiple aftereffects of the same gas logging display are integrated, and the time difference from the gas logging display time to the aftereffect time is fitted to establish an aftereffect gas efficiency function to obtain the total aftereffect release gas amount of the gas logging display;

[0013] f. The open flow capacity of the specific layer system test section of the tested well in the study area is combined with the total aftereffect release gas amount corresponding to the gas logging display in the test section, and the standardization of the drilling fluid density is analyzed to obtain the correlation function of the total aftereffect release gas amount and the open flow capacity;

[0014] g. According to the reservoir evaluation standard of the open flow capacity, the reservoir evaluation standard corresponding to the total aftereffect release gas amount is formed to form an evaluation method for reservoir evaluation of new wells.

[0015] Further, in step c, the total hydrocarbon TG is standardized in base value, time interval and displacement according to the following formula (I):

[0016] TG 标准 = (TG-TG 基值 ) × t 间隔 × V / V 标准 Formula (I),

[0017] In formula (I), TG 标准 is the standard total hydrocarbon; TG is the measured total hydrocarbon; TG 基值 is the total hydrocarbon base value; t 间隔 is the time interval; V is the measured displacement; and V 标准 is the standard displacement.

[0018] Further, in step c, the selection of the total hydrocarbon base value is mainly based on the variation characteristics of the total hydrocarbon curve, and is performed according to the aftereffect description specification; the time interval is based on the actual sampling interval of the logging time data, and the time interval is 0.5-2 min; and the selection of the standard displacement is mainly based on the average value of the parameters commonly used in the study area, and the standard displacement is 10-30 L / s.

[0019] Further, in step d, the aftereffect gas amount M 后效 and the aftereffect gas efficiency η 后效 are calculated according to the following formulas (II) and (III):

[0020] M 后效 =∑TG 标准 (II);

[0021] η 后效 = M 后效 / t 静止 (III).

[0022] In formula (II) and (III), M 后效 is the aftereffect gas volume, η 后效 is the aftereffect gas efficiency, t 静止 is the static time.

[0023] Further, in step e, the aftereffect gas efficiency function is established by fitting as formula (IV) below:

[0024]

[0025] In formula (IV), Δt is the time difference between the gas logging display occurrence time and the aftereffect occurrence time; a, b, and c are fitting parameters.

[0026] Further, in step e, the function integral of the total aftereffect gas release volume adopts the mode of accumulation with the time difference as the axis and recovery to the initial value cutoff, that is, the accumulation is ended when the aftereffect gas efficiency is reduced to the initial value of the function when the time difference is zero, f(cutoff value) = f(0), and the total aftereffect gas release volume satisfies the following formula (V) relationship:

[0027]

[0028] In formula (V), M 后效释放 is the total aftereffect gas release volume.

[0029] Further, in step e, the total aftereffect gas release volumes of multiple gas logging displays in the test section are accumulated.

[0030] Further, in step f, the correlation function of the total aftereffect gas release volume and the open flow capacity is:

[0031] Open flow capacity = F(ΣM 后效释放 × ρ / ρ标标准 ) (VI);

[0032] In formula (VI), ρ is the measured drilling fluid density; ρ 标准 is the standard drilling fluid density.

[0033] Further, the selection basis of the standard drilling fluid density is the average value of the parameters commonly used in the study area.

[0034] Further, in step g, the reservoir evaluation criteria of the open flow capacity have two, one is the upper limit of dry layer, and the other is the lower limit of commercial gas flow,

[0035] When the open flow capacity ≤ the upper limit of dry layer, it is a dry layer;

[0036] When the upper limit of dry layer < the open flow capacity ≤ the lower limit of commercial gas flow, it is a poor gas layer;

[0037] When the open flow capacity > industrial gas flow lower limit, it is a gas layer.

[0038] Further, according to the functional relationship between the total amount of aftereffect released gas and the open flow capacity, and in combination with the reservoir evaluation standard of the open flow capacity, the reservoir evaluation standard of the total amount of aftereffect released gas is correspondingly established, and the reservoir evaluation of the new well is carried out according to the reservoir evaluation standard of the total amount of aftereffect released gas.

[0039] First, the reservoir position is determined according to the gas logging display, and then the total amount of aftereffect released gas of the reservoir of the new well is calculated through steps b-e, and the evaluation result is obtained in combination with the evaluation standard.

[0040] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0041] First, in the present application, the total amount of aftereffect released gas is calculated by standardizing the full hydrocarbon of the aftereffect gas logging, and the aftereffect gas amount and the aftereffect gas efficiency are calculated, the aftereffect gas efficiency function is established by adopting the Gaussian function mode fitting according to the change characteristics of the aftereffect intensity with the reservoir opening time, and the total amount of aftereffect released gas is obtained by integration. The aftereffect released gas amount corresponding to the testing section of the tested oil well after the standardization of the drilling fluid density is fitted with the open flow capacity of the testing section to obtain the correlation function of the two, the reservoir evaluation standard of the aftereffect released gas amount is correspondingly established in combination with the reservoir evaluation standard of the open flow capacity, and the reservoir evaluation method is formed. The evaluation method is reliable.

[0042] Second, in the present application, the aftereffect is innovatively introduced into the reservoir while drilling evaluation system. In the prior art, the aftereffect is used as an engineering evaluation parameter, which is used for evaluating whether the drilling fluid density is reasonable, whether the formation pressure prediction is accurate, whether the circulation time after stopping the pump is sufficient, and other problems related to drilling safety. The present application does not involve reservoir while drilling evaluation. In the present application, the aftereffect is innovatively introduced into the reservoir while drilling evaluation system, and the aftereffect gas amount is taken as a breakthrough. The new parameter, the total amount of aftereffect released gas, is obtained by standardization, function fitting and integration, which objectively reflects the ability of the reservoir to continuously release natural gas to the wellbore after opening. The limitation that no parameter can be used for reservoir while drilling evaluation in the aftereffect parameter is broken, and the parameter basis of reservoir while drilling evaluation is expanded.

[0043] Third, in the present application, the Gaussian function mode fitting is innovatively adopted to establish the aftereffect gas efficiency function. The method of obtaining the total amount of aftereffect gas release by fitting the aftereffect gas efficiency function is not disclosed in the prior art. In the present application, the Gaussian function mode fitting is adopted to establish the aftereffect gas efficiency function according to the unique change characteristics of the aftereffect intensity with the reservoir opening time, the function fitting of the unconventional curve of the aftereffect gas efficiency is realized, the change characteristics of the aftereffect intensity are truly reflected, the total amount of aftereffect gas release obtained by integration is more accurate and reliable, the result difference caused by the inapplicable function is avoided, and the method is more applicable. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is a function fitting of the aftereffect gas efficiency and a cutoff value determination.

[0045] Figure 2 is a function correlation of the total amount of aftereffect release gas and open flow capacity and a reservoir evaluation standard. DETAILED DESCRIPTION

[0046] The application will be further described in connection with the embodiments. However, the embodiments of the application are not limited to this.

[0047] Embodiment 1

[0048] In order to make the public understand the scheme, the embodiment takes the P well area as an example to further illustrate the scheme, relates to the while-drilling geological evaluation technical field, and specifically includes the following steps.

[0049] First step:

[0050] The logging, well logging data and oil testing data of the D layer system of the tested well in the P well area are collected, and the aftereffect corresponding to the gas logging display in the test section is screened out.

[0051] Second step:

[0052] The screened aftereffect is extracted according to the aftereffect time.

[0053] Third step:

[0054] The extracted aftereffect full hydrocarbon data is standardized in the base value, time interval and displacement.

[0055] Since the logging time data is used, the base value, time interval and displacement all have a great influence on the calculation of the aftereffect gas amount, and must be standardized. In this step, the full hydrocarbon TG is standardized in the base value, time interval and displacement according to the following formula (I):

[0056] TG 标准 = (TG-TG 基值 ) × t 间隔 × V / V 标准 Formula (I),

[0057] In formula (I), TG 标准 is the standard full hydrocarbon (%); TG is the measured full hydrocarbon (%); TG 基值 is the full hydrocarbon base value (%); t 间隔 is the time interval (min); V is the measured displacement (L / s); and V 标准 is the standard displacement (L / s).

[0058] In this step, the selection of total hydrocarbon basis value is mainly based on the variation characteristics of total hydrocarbon curve, and is executed according to the aftereffect description specification; the time interval is based on the actual sampling interval of logging time data, and in general cases, the time interval is 0.5-2 min; the selection of standard displacement is mainly based on the average value of parameters commonly used in drilling in the research area, and in general cases, the standard displacement is 10-30 L / s.

[0059] In this embodiment, the standard displacement is 15 L / s.

[0060] Fourth step:

[0061] According to the time from the occurrence to the end of the aftereffect, the aftereffect gas volume is accumulated to obtain the aftereffect gas efficiency, and the static time is combined to calculate the aftereffect gas efficiency.

[0062] In this step, the aftereffect gas volume M 后效 , the aftereffect gas efficiency η 后效 is calculated according to the following formula (II), (III):

[0063] M 后效 =∑TG 标准 (II);

[0064] η 后效 = M 后效 / t 静止 (III);

[0065] In formula (II), (III), M 后效 is the aftereffect gas volume (%), η 后效 is the aftereffect gas efficiency (% / h), and t 静止 is the static time (h).

[0066] In this embodiment, P1 well in P well area which has been tested oil is taken as an example, there is one gas logging display in the test section, and there are four aftereffects, the aftereffect total hydrocarbon measurement is calculated according to the content ratio of hydrocarbon gas in drilling fluid, and the unit is %, and the aftereffect gas efficiency is calculated as 4.5% / h, 16.8% / h, 27.3% / h, and 12.0% / h respectively, and reference is made to Table 1.

[0067] Table 1: P1 well aftereffect gas efficiency calculation parameter statistical table

[0068]

[0069] Fifth step:

[0070] The aftereffect gas efficiency of multiple corresponding aftereffects for the same gas meter is integrated. A Gaussian function is used to fit the aftereffect gas efficiency function to the time difference between the occurrence time of the gas meter and the occurrence time of the aftereffect. The total amount of aftereffect gas released by the gas meter is then calculated by function integration. If multiple gas meters in the test section have corresponding aftereffects, the total amount of aftereffect gas released by the multiple gas meters is summed.

[0071] In this scheme, the function fitted by the collected data can include various types of functions, depending on the different regions to be studied. That is, the function type can be adjusted according to the actual situation of different regions, and the adjustment is based on the data change characteristics and the function having the greatest fit rate.

[0072] Based on the characteristics of gas wells studied recently, as the reservoir opening time increases, the aftereffect intensity will increase rapidly from zero and then gradually decrease back to zero. This is inconsistent with the characteristics of conventional exponential, logarithmic, and higher-order functions. Therefore, a Gaussian function model that better matches this change characteristic was adopted for fitting.

[0073] In this scheme, the after-effect gas efficiency function is fitted and established as the following equation (Ⅳ):

[0074]

[0075] In equation (Ⅳ), Δt is the time difference between the time of gas measurement and the time of aftereffect occurrence; a, b, and c are fitting parameters.

[0076] In this embodiment, the gas measurement displays the four corresponding after-effect gas efficiencies, for reference. Figure 1 The after-effect gas efficiency function was established by fitting the time difference between the time of occurrence of the gas measurement and the time of occurrence of the aftereffect using a Gaussian function model, as follows:

[0077]

[0078] The integral of the function representing the total amount of aftereffect gas is calculated by accumulating along the time difference axis and stopping at the initial value. That is, the accumulation ends when the efficiency of the aftereffect gas decreases to the initial value of the function when the time difference is zero. When f(cutoff value) = f(0), the total amount of aftereffect gas satisfies the following relationship (V):

[0079]

[0080] In the formula, M 后效释放 This represents the total amount of gas released after the effect.

[0081] In this embodiment, based on the initial value of the aftereffect gas efficiency function f(0) = 0.03, the cutoff value is determined to be 155, i.e., f(155) = f(0). The total aftereffect gas released by the gas meter is calculated to be 1507.5, which is the total aftereffect gas released in this test section.

[0082]

[0083] Step 6:

[0084] The total amount of after-release gas corresponding to the open flow capacity of the test section of the specific layer system of the tested well in the research area is tested by gas logging, and the correlation analysis is conducted in combination with the standardization of drilling fluid density to obtain the correlation function of the total amount of after-release gas and the open flow capacity.

[0085] In this step, the correlation function of the total amount of after-release gas and the open flow capacity is:

[0086] Open flow capacity = F(∑M 后效释放 ×ρ / ρ 标准 ) (VI);

[0087] In the formula, ρ is the measured drilling fluid density; and ρ 标准 is the standard drilling fluid density.

[0088] Due to the difference in geological conditions, the relationship between the open flow capacity and the total amount of after-release gas is different in different regions and different layer systems, and therefore the type of function F is variable, which is generally a linear function, and can also be an exponential function, a logarithmic function, a high-order function, etc. The selection of the standard drilling fluid density is mainly based on the average value of the parameters commonly used in drilling in the research area.

[0089] In this embodiment, the total amount of after-release gas corresponding to the open flow capacity of the test section of the D layer system of the tested well in the research area is tested by gas logging, and the correlation analysis is conducted in combination with the standardization of drilling fluid density to obtain the correlation function of the total amount of after-release gas and the open flow capacity, which is referred to Figure 2 . The standard drilling fluid density is 1.35 g / cm 3 .

[0090] Open flow capacity = F(M 后效释放 ×ρ / ρ 标准 ) = 194.7 × M 后效释放 - 16877.

[0091] Step 7:

[0092] According to the reservoir evaluation standard of the open flow capacity, the reservoir evaluation standard of the total amount of after-release gas is formed to form an evaluation method for reservoir evaluation of new wells.

[0093] In this step, the reservoir evaluation standard of the open flow capacity has two, one is the upper limit of dry layer, and the other is the lower limit of commercial gas flow,

[0094] When the open flow capacity ≤ the upper limit of dry layer, it is a dry layer;

[0095] When the upper limit of the dry layer < the open flow capacity ≤ the lower limit of the industrial gas flow, it is a poor gas layer.

[0096] When the open flow capacity > the lower limit of the industrial gas flow, it is a gas layer.

[0097] According to the functional relationship between the total amount of aftereffect released gas and the open flow capacity, and in combination with the reservoir evaluation standard of the open flow capacity, the reservoir evaluation standard of the total amount of aftereffect released gas is correspondingly established.

[0098] According to the reservoir evaluation standard of the total amount of aftereffect released gas, the reservoir of a new well can be evaluated, that is, the reservoir position is first determined according to the gas logging display, and then the total amount of aftereffect released gas of the reservoir of the new well is calculated through steps b-e, and the evaluation result is obtained in combination with the evaluation standard.

[0099] In the embodiment, according to the reservoir evaluation standard of the open flow capacity, referring to Table 2, the D layer system of the P well area belongs to land and the reservoir burial depth > 4000 m,

[0100] The reservoir evaluation standard is: when the open flow capacity ≤ 600 m 3 / d, it is a dry layer; when 600 m 3 / d < the open flow capacity ≤ 20000 m 3 / d, it is a poor gas layer; and when the open flow capacity > 20000 m 3 / d, it is a gas layer.

[0101] The reservoir evaluation standard of the total amount of aftereffect released gas is: when the total amount of aftereffect released gas ≤ 90.8, it is a dry layer; when 90.8 < the total amount of aftereffect released gas ≤ 189.4, it is a poor gas layer; and when the total amount of aftereffect released gas > 189.4, it is a gas layer.

[0102] Table 2: The reservoir evaluation standard of the open flow capacity.

[0103]

[0104] According to the reservoir evaluation standard of the total amount of aftereffect released gas, the reservoir of a new well can be evaluated, that is, the reservoir position is first determined according to the gas logging display, and then the total amount of aftereffect released gas of the reservoir of the new well is calculated through steps 2-6, and the evaluation result is obtained in combination with the evaluation standard.

[0105] The above is only a preferred embodiment of the present application, and does not limit the present application in any form, and any simple modification or equivalent change made according to the technical essence of the present application to the above embodiment falls within the protection scope of the present application.

Claims

1. A method for reservoir evaluation based on the amount of gas released after the effect, characterized by, It comprises the following steps: a. Collect the logging, well logging data and testing data of the specific layer of the tested well in the study area, and screen the corresponding aftereffect of the test section from the gas logging display; b. According to the aftereffect time, extract the corresponding total hydrocarbon data of the screened aftereffect; c. Standardize the total hydrocarbon data of the extracted aftereffect in terms of base value, time interval and discharge capacity; d. According to the time from the occurrence to the end of the aftereffect, accumulate the standard total hydrocarbon to obtain the aftereffect gas volume, and then calculate the aftereffect gas efficiency in combination with the static time; e. Integrate the aftereffect gas efficiencies of multiple aftereffects corresponding to the same gas logging display, and fit the aftereffect gas efficiency function with the time difference from the occurrence time of the gas logging display to the occurrence time of the aftereffect, so as to obtain the total aftereffect released gas of the gas logging display, In this step, the aftereffect gas efficiency function is fitted as formula (IV): （Ⅳ）； In formula (IV), Δ t is the time difference from the onset time to the aftereffect onset time; a, b, c is a fitting parameter; f. Correlate the total aftereffect released gas and the open flow capacity of the test section of the specific layer of the tested well in the study area in combination with the standardization of the drilling fluid density, so as to obtain the correlation function of the total aftereffect released gas and the open flow capacity, In this step, the correlation function of the total aftereffect released gas and the open flow capacity is: （Ⅵ）； wherein ρ is the measured drilling fluid density; ρ 标准 is the standard drilling fluid density; g. According to the reservoir evaluation standard of the open flow capacity, the reservoir evaluation standard corresponding to the total aftereffect released gas is formed to form an evaluation method for reservoir evaluation of new wells.

2. The method for reservoir evaluation based on the amount of gas released by aftereffect according to claim 1, characterized in that: Total hydrocarbons in step c TG The base value, time interval, and displacement are normalized by the following equation (I): TG 标准 = (1 - x) x TG - TG 基值 ) x (1 - x) t 间隔 x (1 - x) V / V 标准 Formula (I), In formula (I), TG 标准 is standard total hydrocarbon; TG is measured total hydrocarbon; TG 基值 is total hydrocarbon base value; t 间隔 is time interval; V is measured displacement; V 标准 is standard displacement.

3. The method for reservoir evaluation based on the amount of gas released by aftereffect of claim 2, characterized in that: In step c, the selection basis of the total hydrocarbon base value is the variation characteristics of the total hydrocarbon curve, which is executed according to the aftereffect description specification; the time interval is the actual sampling interval of the logging time data, and the time interval is 0.5-2 min; the selection basis of the standard discharge capacity is the average value of the parameters commonly used in the drilling of the study area, and the standard discharge capacity is 10-30 L / s.

4. The method for reservoir evaluation based on the amount of gas released by aftereffect of claim 1, characterized in that: The amount of aftereffect gas in step d M 后效 The aftereffect gas efficiency η 后效 The following formula (II), (III) is calculated: M 后效 =∑ TG 标准 （Ⅱ）； η 后效 = M 后效 / t 静止 （Ⅲ）； In formula (II), (III), M 后效 is the aftereffect gas amount, η 后效 is the aftereffect gas efficiency, t 静止 is the rest time.

5. The method for reservoir evaluation based on the amount of gas released by aftereffect of claim 1, characterized in that: In step e, the function integral of the total amount of aftereffect released gas adopts a mode of accumulation with time difference as the axis and recovery to the initial value cutoff, that is, the accumulation ends when the aftereffect gas efficiency is reduced to the initial value of the function when the time difference is zero, f (cutoff value) = 0 f When t = 0, the total amount of aftereffect released gas satisfies the following formula (V): （Ⅴ）； In the formula, M 后效释放 is the total amount of post-effect release gas.

6. The method for reservoir evaluation based on the amount of gas released by aftereffect of claim 1, characterized in that: In step e, there are multiple gas logging displays in the test section, and each gas logging display has a corresponding aftereffect, so the total aftereffect released gas of multiple gas logging displays is accumulated.

7. The method for reservoir evaluation based on the amount of gas released by aftereffect of claim 1, characterized in that: The selection basis of the standard drilling fluid density is the average value of the parameters commonly used in the drilling of the study area.

8. The method for reservoir evaluation based on the amount of gas released by aftereffect of claim 1, characterized in that: In step g, the reservoir evaluation standard of the open flow capacity has two, one is the upper limit of dry layer, and the other is the lower limit of industrial gas flow, When the open flow capacity is less than or equal to the upper limit of dry layer, it is a dry layer; When the upper limit of dry layer is less than the open flow capacity and the open flow capacity is less than or equal to the lower limit of industrial gas flow, it is a poor gas layer; When the open flow capacity is greater than the lower limit of industrial gas flow, it is a gas layer.

9. The method for reservoir evaluation based on the amount of gas released by aftereffect of claim 8, characterized in that: According to the functional relationship between the total aftereffect released gas and the open flow capacity, in combination with the reservoir evaluation standard of the open flow capacity, the reservoir evaluation standard corresponding to the total aftereffect released gas is established, and the reservoir evaluation standard of the total aftereffect released gas is used to evaluate the reservoir of new wells: First, determine the reservoir position according to the gas logging display, then calculate the total aftereffect released gas of the new well reservoir through steps b-e, and finally obtain the evaluation result in combination with the evaluation standard.

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