Method and device for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors

Abstract

The present disclosure relates to the technical field of oil exploration and development, and particularly relates to a method and device for predicting recoverable reserves of an oil and gas reservoir based on uncertain factors. The corresponding method comprises the following steps: determining a prediction frequency of the recoverable reserves of the oil and gas reservoir according to the production stability of a production well of the oil and gas reservoir; predicting the production loss of the production well according to historical production influence data and future production influence data of the production well; determining corresponding production capacity parameters according to the current actual production and the production loss of the production well according to the current prediction frequency and the well type; and predicting the recoverable reserves of the oil and gas reservoir according to the production capacity parameters of all production wells of the oil and gas reservoir and a future drilling sequence. The present disclosure improves the prediction accuracy of the production decline law of various production wells by introducing the production loss, and at the same time, by analyzing the uncertainty that may occur in the future of each part of the key parameters, different schemes for predicting the recoverable reserves are obtained, which can be effectively applied to various oil and gas reservoirs.

Description

Technical Field

[0001] This disclosure relates to the field of petroleum exploration and development technology, specifically to a method, apparatus, equipment, storage medium, and computer program for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors. Background Technology

[0002] In existing methods for assessing oil and gas reservoir reserves, it is necessary to treat all wells in a three-dimensional space defined by a certain range on the plane and a row of strata on the vertical as individual assessment units. Their past production, cost, investment, and economic indicators are statistically analyzed, and future production is predicted and calculated in order to arrange the production plan for the following year. The most important part is the prediction of recoverable reserves. Commonly used methods for predicting recoverable reserves include numerical simulation, production decline method, and empirical formula method. Among them, the production decline method is the most commonly used because of its simple calculation method and high calculation accuracy.

[0003] The production decline method includes the overall unit decline method, which analyzes and evaluates the overall production curves of all regular units within a block. This method divides the production into two parts: old wells and new wells, and studies them separately. However, this method does not take into account factors such as the introduction of new wells in the block, artificial production restrictions, and short-term measures, which cause production to fluctuate and obscure the true decline pattern of the gas reservoir. Therefore, its prediction results are often not reasonable. Summary of the Invention

[0004] This disclosure provides a method, apparatus, equipment, storage medium, and computer program for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors. By introducing production loss parameters, it further reduces production changes caused by factors such as human-induced production restrictions and short-term measures, thereby improving the accuracy of production prediction. At the same time, it conducts uncertainty analysis on the production prediction results, analyzes possible future scenarios, makes predictions for each scenario, obtains production prediction results under various possibilities, and finally obtains different production prediction schemes.

[0005] Firstly, this disclosure provides a method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, including:

[0006] The frequency of predicting the recoverable reserves of an oil and gas reservoir is determined based on the production stability of its production wells.

[0007] The production loss of the production well is predicted based on the historical production impact data and future production impact data of the production well;

[0008] Based on the current forecast frequency and well type, determine the corresponding production capacity parameters according to the current actual output of the production well and the output loss.

[0009] The recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all producing wells and the future drilling sequence.

[0010] In some embodiments of this disclosure, the production stability of the production well includes: an increasing production state, a stable production state, and a decreasing production state; wherein the decreasing state includes: an early decreasing state, a middle decreasing state, and a late decreasing state.

[0011] In some embodiments of this disclosure, when the production stability of the production well is in a decreasing state, the recoverable reserves of the oil and gas reservoir are predicted once a year.

[0012] In some embodiments of this disclosure, the historical production impact data includes: well workover, well shut-in, and production restriction;

[0013] The data on future production impacts include: anticipated well workovers, well shutdowns, production cuts, and equipment depreciation.

[0014] In some embodiments of this disclosure, determining the corresponding production capacity parameters based on the current actual production of the production well and the production loss, according to the current prediction frequency and well type, includes:

[0015] At the current prediction frequency, the production capacity parameters of all production wells of each well type are determined based on the current actual production of the production wells and the production loss; wherein, the production stability of multiple production wells corresponding to the current prediction frequency is the same.

[0016] In some embodiments of this disclosure, the recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all producing wells and the future drilling sequence, including:

[0017] Predict the future production decline rate of production wells of the corresponding well type based on the aforementioned production capacity parameters;

[0018] The recoverable reserves of the oil and gas reservoir are predicted based on the production decline rate and the future drilling sequence.

[0019] Secondly, this disclosure provides a device for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, comprising:

[0020] The prediction frequency determination module is used to determine the prediction frequency of the recoverable reserves of the oil and gas reservoir based on the production stability of the production wells in the oil and gas reservoir.

[0021] The production loss prediction module is used to predict the production loss of the production well based on the historical production impact data and future production impact data of the production well.

[0022] The production capacity parameter determination module is used to determine the corresponding production capacity parameters based on the current actual output of the production well and the output loss, according to the current prediction frequency and well type.

[0023] The recoverable reserves prediction module is used to predict the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the reservoir and the future drilling sequence.

[0024] In some embodiments of this disclosure, the production stability of the production well includes: an increasing production state, a stable production state, and a decreasing production state; wherein the decreasing state includes: an early decreasing state, a middle decreasing state, and a late decreasing state.

[0025] In some embodiments of this disclosure, when the production stability of the production well is in a decreasing state, the recoverable reserves of the oil and gas reservoir are predicted once a year.

[0026] In some embodiments of this disclosure, the historical production impact data includes: well workover, well shut-in, and production restriction;

[0027] The data on future production impacts include: anticipated well workovers, well shutdowns, production cuts, and equipment depreciation.

[0028] In some embodiments of this disclosure, the production capacity parameter determination module includes:

[0029] A production capacity parameter determination unit is used to determine the production capacity parameters of all production wells of each well type based on the current actual output of the production wells and the output loss at the current prediction frequency; wherein the output stability of multiple production wells corresponding to the current prediction frequency is the same.

[0030] In some embodiments of this disclosure, the recoverable reserves prediction module includes:

[0031] The production decline rate prediction unit is used to predict the future production decline rate of production wells of the corresponding well type based on the production capacity parameters.

[0032] A recoverable reserves prediction unit is used to predict the recoverable reserves of the oil and gas reservoir based on the production decline rate and the future drilling sequence.

[0033] Thirdly, this disclosure provides a computer device including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in the foregoing aspects.

[0034] Fourthly, this disclosure provides a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps of the methods described in the above aspects.

[0035] Fifthly, this disclosure provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of the methods described in the foregoing aspects.

[0036] This disclosure provides a method, apparatus, equipment, storage medium, and computer program for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors. The corresponding method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors includes: first, determining the prediction frequency of recoverable reserves of the oil and gas reservoir based on the production stability of the production wells; next, predicting the production loss of the production wells based on historical production impact data and future production impact data; determining the corresponding production capacity parameters based on the current actual production and production loss of the production wells according to the current prediction frequency and well type; and finally, predicting the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the oil and gas reservoir and the future drilling sequence.

[0037] In summary, the method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors provided in this disclosure improves the prediction accuracy of the decline law of various production wells by introducing production loss. At the same time, by analyzing the uncertainty that may occur in the future of each key parameter, different schemes for predicting recoverable reserves are obtained, which can be effectively applied to various oil and gas reservoirs. Attached Figure Description

[0038] The present disclosure will be described in more detail below based on embodiments and with reference to the accompanying drawings:

[0039] Figure 1 This is a schematic flowchart illustrating a method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, provided in an embodiment of this disclosure.

[0040] Figure 2 This is a flowchart illustrating step 300 of a method for predicting recoverable oil and gas reservoir reserves based on uncertain factors, provided in an embodiment of this disclosure.

[0041] Figure 3 This is a flowchart illustrating step 400 of a method for predicting recoverable oil and gas reservoir reserves based on uncertain factors, provided in an embodiment of this disclosure.

[0042] Figure 4 This is a flowchart illustrating a method for predicting recoverable oil and gas reservoir reserves based on uncertain factors, provided as an application example of this disclosure.

[0043] Figure 5 A logic diagram of a method for predicting recoverable oil and gas reservoir reserves based on uncertain factors, provided as an application example of this disclosure.

[0044] Figure 6The chart showing the historical production efficiency trend of reservoir A, provided as an application example in this public disclosure.

[0045] Figure 7 The chart showing the IPC variation trend of wells put into production in reservoir A over the years, provided as an application example in this public disclosure.

[0046] Figure 8 A block diagram of an apparatus for predicting recoverable oil and gas reservoir reserves based on uncertain factors, provided in an embodiment of this disclosure.

[0047] In the accompanying drawings, the same parts are referred to by the same reference numerals, and the drawings are not drawn to scale. Detailed Implementation

[0048] To enable those skilled in the art to better understand the technical solutions of this disclosure, and to fully understand and implement the process of how this disclosure applies technical means to solve technical problems and achieve corresponding technical effects, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, not all embodiments. The embodiments of this disclosure and the various features within them can be combined with each other without conflict, and the resulting technical solutions are all within the protection scope of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort should fall within the protection scope of this disclosure.

[0049] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0050] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0051] Example 1

[0052] This disclosure provides a method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors. Figure 1 This is a flowchart illustrating a method for predicting recoverable oil and gas reservoir reserves based on uncertainties, provided as an embodiment of this disclosure. Figure 1 As shown, a method for predicting recoverable reserves of oil and gas reservoirs based on uncertainties includes:

[0053] Step 100: Determine the prediction frequency of the recoverable reserves of the oil and gas reservoir based on the production stability of the production wells in the oil and gas reservoir.

[0054] Step 200: Predict the production loss of the production well based on the historical production impact data and future production impact data of the production well;

[0055] Step 300: Based on the current prediction frequency and well type, determine the corresponding production capacity parameters according to the current actual production of the production well and the production loss.

[0056] Step 400: Predict the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the reservoir and the future drilling sequence.

[0057] This disclosure provides a method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, comprising: first, determining the prediction frequency of recoverable reserves of the oil and gas reservoir based on the production stability of the production wells; next, predicting the production loss of the production wells based on historical production impact data and future production impact data; determining the corresponding production capacity parameters based on the current actual production and production loss of the production wells according to the current prediction frequency and well type; and finally, predicting the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the oil and gas reservoir and the future drilling sequence.

[0058] As described above, this disclosure establishes a method for predicting the recoverable reserves of oil and gas reservoirs that considers production uncertainty. Based on a relatively accurate prediction of recoverable reserves, it can simultaneously obtain different prediction schemes for recoverable reserves according to possible future scenarios. This method is applicable to various types of oil and gas reservoirs. This invention is simple, practical, and suitable for large-scale application.

[0059] Example 2

[0060] The prediction frequency in step 100 refers to how often the recoverable reserves of an oil and gas reservoir are predicted. For example, recoverable reserves are predicted once a year, once every two years, and so on.

[0061] Furthermore, the stability of oil and gas well production refers to the ability of an oil and gas well to maintain a relatively constant production rate and pressure over a certain period of time, ensuring a continuous and effective oil and gas recovery process. Production stability is a crucial indicator in oil and gas field management and development, directly impacting the economic benefits, operating costs, and long-term production planning of the entire oilfield. Factors affecting the production stability of oil and gas wells include, but are not limited to, the following:

[0062] Formation pressure*: Maintaining formation pressure is crucial for ensuring the stability of oil and gas well production. If formation pressure drops too rapidly, it can lead to a rapid decline in production and may even cause blowouts or lost circulation. To maintain pressure, measures such as water injection or gas injection are often employed.

[0063] Reservoir properties: The permeability, porosity, rock type, and physical properties of oil and gas (such as viscosity and gas-oil ratio) of the reservoir all affect the flow of oil and gas in the reservoir. If the reservoir has poor homogeneity or natural fractures, it may lead to large fluctuations in production and affect the stability of production.

[0064] Production methods: The choice of production method (such as natural flow, artificial lift, fracturing, etc.) directly affects the productivity and stability of oil and gas wells. A suitable production method can slow down the rate of decline and maintain a relatively stable production level.

[0065] Mechanical equipment and wellbore conditions: The condition and maintenance of downhole equipment (such as pumping units, pumps, pipelines, etc.) affect the continuity and stability of production. The integrity of the wellbore (such as intact well walls and no leakage) is also crucial to the stability of production.

[0066] External conditions: Natural factors such as earthquakes and climate change, or external damage to pipelines and equipment, can affect the production stability of oil and gas wells.

[0067] To ensure the long-term stable production of oil and gas wells, the following measures can be taken:

[0068] Maintaining formation pressure: Formation pressure is maintained through techniques such as water injection, gas injection, and polymer injection to prevent a rapid drop in pressure that could lead to unstable production.

[0069] Optimize production parameters: Adjust production parameters (such as oil pressure, flow rate, gas-oil ratio, etc.) according to actual production conditions to optimize output. Avoid excessively fast oil extraction rates to prevent the "cone" phenomenon, which leads to increased water cut and a sharp drop in production.

[0070] Regular maintenance of downhole equipment: Regularly inspect and maintain downhole equipment, replace aging or damaged equipment in a timely manner, ensure normal operation of equipment, and avoid production interruptions due to equipment failure.

[0071] Implement production enhancement measures: When production begins to decline, implement production enhancement measures such as fracturing and acidizing to reactivate the reservoir and maintain stable production.

[0072] Monitoring and Data Analysis: Real-time monitoring of downhole production status through advanced downhole monitoring equipment (such as flow meters, pressure gauges, etc.), combined with big data analysis, to promptly identify potential problems and take proactive countermeasures.

[0073] For step 200, the production losses caused by human factors such as well repair, well shutdown, and production restriction in each historical month are statistically analyzed. Based on the historical production loss trend and in combination with the possible future scheduled well repair, well shutdown, and production restriction factors, future production losses are predicted.

[0074] Preferably, to simplify calculations, the predicted production loss can be calculated based on the average of previous production losses.

[0075] For step 300, for each production well in each category, the production capacity parameter (in barrels or tons) of that production well is calculated by summing the actual output and the output loss.

[0076] For step 400, the drilling sequence of the oil and gas field plan refers to the reasonable arrangement of the drilling order of each oil and gas well during the development of the oil and gas field, based on factors such as geological reservoir distribution, production targets, economic benefits and technical feasibility.

[0077] Determining the drilling sequence can be considered from the following perspectives:

[0078] Geological conditions include reservoir distribution, oil and gas content and quality, formation pressure, permeability, and porosity. A thorough understanding of geological conditions helps determine priority drilling areas and target strata.

[0079] Production planning: Drilling sequences need to be arranged according to the overall development plan and production targets of the oil and gas field. Priority is usually given to developing blocks with higher production potential and economic value.

[0080] Economic benefits: The economic benefits of development must be considered, including initial investment, operating costs, and oil and gas sales revenue. Drilling is typically prioritized in areas where costs can be recovered quickly and yield higher returns.

[0081] Technical feasibility: The feasibility of drilling technology is also an important factor. For some geologically complex blocks or those with technical challenges, it may be necessary to adjust the drilling sequence or adopt special technologies.

[0082] Infrastructure and Logistics: The drilling sequence also needs to consider existing infrastructure (such as roads, pipelines, production facilities, etc.) and logistics conditions to ensure the efficient operation of drilling activities.

[0083] A reasonable drilling sequence design should follow these principles:

[0084] The principle of gradual advancement: Drilling activities will be advanced gradually according to the development stage of the oil and gas field. Initial drilling will focus on areas with better geological conditions and higher production potential, and later it will gradually expand to areas with more complex geological conditions.

[0085] The principle of balanced development: Maintain a balance in production across different development blocks, avoid over-exploitation or a sharp drop in production in a single area, and ensure the long-term stable production of the entire oil and gas field.

[0086] Zoning development principle: Based on the geological characteristics of the oil and gas field, the field is divided into several development blocks, and drilling is carried out step by step according to the blocks. This can effectively control the development pace and optimize resource allocation.

[0087] Flexible adjustment principle: In the actual development process, the drilling sequence is flexibly adjusted according to production data and market conditions to ensure the best economic benefits.

[0088] Example 3

[0089] Based on the above embodiments, the production stability of the production well includes: an increasing production state, a stable production state, and a decreasing production state; wherein, the decreasing state includes: an early decreasing state, a middle decreasing state, and a late decreasing state.

[0090] In some embodiments of this disclosure, when the production stability of the production well is in the state of increasing production and stable production, numerical simulation prediction results are used. For those without numerical simulation results or with poor historical fitting effect of numerical models, the stable production time and decline law of similar reservoirs in the surrounding area are used for comparison. It is assumed that they have the same stable production time and decline law, that is, the same decline rate Di and b, for prediction.

[0091] In some embodiments of this disclosure, when the production stability of the production well is in a declining state, the production decline method is used to predict the decline for each well using Arps decline. The Arps decline equation is as follows:

[0092] q t =q i (1+bD i t) -1 / b

[0093]

[0094] In the formula, qt is the output at time t, Np is the cumulative output at time t, qi is the initial output of the declining prediction, b is the declining parameter, and Di is the declining rate.

[0095] In some embodiments of this disclosure, when the production stability of the production well is in a declining state, if a reservoir has a stable decline in the number of wells except for one or two wells with abnormal decline, and the number of wells with stable decline is greater than the number of wells with abnormal decline, the reservoir can be treated as a whole and the production decline method can be used for prediction. Generally speaking, the simpler Arps decline method should be used as much as possible when predicting decline. Only when Arps decline is difficult to predict or the prediction results have obvious problems, such as when the reservoir is analyzed as an unconventional reservoir with adsorption and desorption characteristics, the SEPC or Duong method should be used for decline prediction.

[0096] In some embodiments of this disclosure, when the production output of the production well is unstable and difficult to classify into specific states, i.e., it is impossible to find a production well with a stable production system and a clear decline segment on the production curve that can be used for Arps decline analysis, the relationship between daily production and time in the decline analysis can be changed to the relationship between cumulative production and well opening time for Arps decline analysis. If there are production wells with stable production segments and reliable decline analysis results in the same or similar reservoirs, an analogy method can be used to refer to the key Arps decline parameters Di and b predicted by stable declining production wells in the same or similar reservoirs. The average production of the unstable production well over the past month (for wells with low well opening time rates, this can be extended to the average production of the past three months) is taken as the initial production for decline pattern prediction.

[0097] The increasing production stage refers to the initial production phase of an oil and gas well, where, due to sufficient reservoir energy and high downhole pressure, oil and gas can flow smoothly from the formation to the wellbore, resulting in a gradual increase in wellhead production. During this stage, the oil and gas well exhibits the following characteristics:

[0098] High pressure: Formation pressure remains at a high level, providing sufficient energy to drive oil and gas flow.

[0099] Increased flow rate: As production time progresses, the flow channel gradually expands, the oil and gas flow rate increases, and the output gradually increases.

[0100] Extraction potential: At this stage, oil and gas wells are generally considered to have significant extraction potential.

[0101] A stable production state refers to a situation where, during the production process of an oil and gas well, the production rate reaches a relatively stable level and remains unchanged for a certain period of time. In this stage, downhole conditions (such as pressure and flow rate) are relatively balanced, and the producing well exhibits the following characteristics:

[0102] Equilibrium state: Reservoir pressure and wellbore flow resistance reach equilibrium, and production is maintained at a relatively stable level.

[0103] Stable production: At this time, oil and gas production is relatively stable and will not fluctuate significantly, making it the golden period for oil and gas field development.

[0104] Duration: The duration of stable production depends on factors such as reservoir conditions, production methods, and reservoir management strategies.

[0105] The production decline phase refers to the period after a stable production phase in oil and gas wells, during which production gradually decreases due to declining formation pressure and insufficient driving energy. The production decline phase is divided into three stages:

[0106] Early stage of the declining state:

[0107] Production begins to decline: Wellbore production gradually decreases, but the decline is relatively slow.

[0108] Reservoir energy depletion: Although formation pressure remains high, energy supply has begun to become insufficient, leading to a decline in production.

[0109] Adjustment phase: In this phase, by optimizing production parameters or taking measures to increase production, the rate of decline in output can be partially slowed down.

[0110] Mid-stage of the declining state:

[0111] Significant decline in output: The rate of decline in output accelerates, and the curve becomes steeper.

[0112] Significantly reduced pressure: Formation pressure drops significantly, resulting in insufficient energy to drive oil and gas flow.

[0113] Reduced profitability: Due to declining production, the economic benefits of oil and gas wells have begun to decrease significantly.

[0114] End of the declining state:

[0115] Production declines sharply: Production is nearing depletion, the rate of decline is slowing, and it is approaching the economic limit.

[0116] Inefficient production: At this stage, production is often inefficient, and the cost of maintaining production gradually exceeds the revenue. Typically, at this stage, oil and gas wells will face closure or conversion into auxiliary wells (such as water injection wells or gas injection wells) to support other production wells.

[0117] Based on the above embodiments, when the production stability of the production well is in a decreasing state, the recoverable reserves of the oil and gas reservoir are predicted once a year.

[0118] Based on the above embodiments, the historical production impact data includes: well workover, well shut-in, and production restriction;

[0119] The data on future production impact includes anticipated well workovers, well shutdowns, production restrictions, and equipment depreciation. When predicting future production impact data, historical production losses due to well workovers, well shutdowns, and production restrictions in the same or similar reservoirs are statistically analyzed, and the proportion of these losses to the current year's production is calculated to obtain the average historical production loss percentage for each reservoir. For wells that have been in production for less than 5 years, the average of the statistical results can be used for production losses in the next 3 years; for wells that have been in production for more than 5 years, the average of the statistical results can be used for production losses in the next 2 years. For production losses exceeding these ranges, a 3% increase in production loss every 3 years can be used for calculation. If neighboring similar reservoirs have a longer production history, the increase in production losses in similar reservoirs can be statistically analyzed for comparison.

[0120] Well workover refers to a series of operations performed during oil and gas well production to repair, clean, or improve the wellbore or formation due to wellbore problems, equipment malfunctions, changes in formation conditions, or the need for enhanced production operations. These operations include the following:

[0121] Wellbore cleaning: Removing sediments, impurities, or wax from the wellbore to restore the smooth flow of the wellbore.

[0122] Downhole equipment maintenance: Replacement or repair of downhole equipment, such as sucker rods, pumps, packers, etc., to ensure normal operation of the equipment.

[0123] Acidizing and fracturing: Acidizing or fracturing operations are performed on the reservoir to increase formation permeability and improve oil and gas flow.

[0124] Repairing well leaks: Repairing well leaks or sealing non-productive layers to prevent formation fluid loss and maintain stable production.

[0125] Well shut-in refers to the temporary or permanent cessation of production from an oil or gas well. Well shut-in can be for a variety of reasons, including:

[0126] Production adjustment: Oil and gas wells need to be temporarily shut down for well workover operations or equipment maintenance.

[0127] Market factors: When oil and gas prices are low, wells are shut down to reduce losses and wait for the market to recover.

[0128] Reservoir protection: To prevent excessive drop in formation pressure or water flooding, the wellhead is temporarily closed to maintain reservoir stability.

[0129] Termination of production: When the production of an oil and gas well drops to a level that makes it uneconomical to extract, the well may be permanently shut down.

[0130] Production restriction refers to limiting oil and gas production by adjusting the production parameters of oil and gas wells (such as production flow rate, water injection rate, etc.).

[0131] Equipment depreciation refers to the process by which the value of production equipment gradually decreases over time during oil and gas field production. Equipment depreciation reflects the equipment's useful life and its diminishing value in accounting. Common depreciation methods include the straight-line method, the double-declining balance method, and the sum-of-the-years'-digits method. Different methods affect how depreciation expenses are calculated.

[0132] The calculation of depreciation is affected by factors such as the initial investment in the equipment, its estimated useful life, residual value, and workload. Equipment depreciation expense is treated as a fixed cost in accounting, affecting a company's profit calculation and tax burden.

[0133] Example 4

[0134] Based on the above embodiments, see Figure 2 Step 300 includes:

[0135] Step 301: Under the current prediction frequency, determine the production capacity parameters of all production wells of each well type based on the current actual production of the production wells and the production loss; wherein, the production stability of multiple production wells corresponding to the current prediction frequency is the same.

[0136] First, wells are classified into three types according to their shape: vertical wells, deviated wells, and horizontal wells. Vertical wells are those where the wellbore is drilled roughly vertically downwards from the surface to the target oil and gas reservoir. Deviated wells are those where the wellbore gradually changes direction after drilling downwards from the surface, eventually entering the target reservoir at a certain angle. Horizontal wells are those where the wellbore continues to change direction from its vertical or deviated trajectory, ultimately drilling parallel to the formation within the target oil and gas reservoir.

[0137] For reservoirs where dynamic analysis shows little difference between deviated and horizontal wells, they can be divided into two categories: vertical wells and deviated wells.

[0138] Next, for each production well in each category, the production capacity (IPC) of the production well is calculated by summing the actual production and the production loss, and the recoverable reserves are predicted using the production capacity (IPC).

[0139] Specifically, for the identified stable production wells, the analogy method is used to refer to old wells with similar reservoir conditions in the same or similar reservoirs for prediction.

[0140] Specifically, for production wells with a steady decline in monthly production capacity (IPC), the production decline method is used to predict the production of each well separately, or the production wells of this type are predicted as a whole.

[0141] Specifically, for production wells with unstable monthly production capacity (IPC), the analogy method is used to refer to stable declining production wells in the same or similar reservoirs for prediction.

[0142] Specifically, for new wells with short operating times and unclear decline patterns, predictions can be made by referring to the production patterns of new wells in the same reservoir in the past, or by using the analogy method to refer to old wells in the same or similar reservoirs with similar reservoir conditions.

[0143] Specifically, while analyzing the decline patterns of various production wells, and combining reservoir management planning and production dynamics analysis, we predict possible future decline rate changes, and use the different decline rate prediction results as prediction results for different schemes.

[0144] Based on the above embodiments, see Figure 3 Step 400 includes:

[0145] Step 401: Predict the future production decline rate of the corresponding well type based on the production capacity parameters;

[0146] While analyzing the decline patterns of various production wells, and combining reservoir management planning and production dynamics analysis, we predict possible future decline rate changes, and use the different decline rate prediction results as prediction results for different schemes.

[0147] Step 402: Predict the recoverable reserves of the oil and gas reservoir based on the production decline rate and the future drilling sequence.

[0148] For wells to be drilled in the future, the numerical simulation results during the drilling design will be used as the basic prediction results. At the same time, the differences between the historical production effects of new wells and the prediction results will be considered, and the production allocation and decline rate of different new wells will be optimized as the prediction results of different schemes.

[0149] In steps 401 and 402, for each type of production well, the IPC (Incremental Production Capacity) is calculated by summing the actual production and production loss, and production is predicted using the IPC. Next, the production launch time of new wells not yet in production is determined by combining the latest drilling sequence, and the numerical simulation results from the drilling design are used as the basis for the prediction results. Finally, the production prediction results for each type of production well and the production prediction results for the wells to be drilled are added together to obtain multiple schemes for the final prediction of the cumulative recoverable reserves of the reservoir.

[0150] Based on the above embodiments, the specific implementation of step 100 is as follows: For each well type (vertical well, deviated well, and horizontal well), the assessment year is reasonably divided according to the actual production situation of each well, based on the stability of production, whether it is in a declining phase, and whether it is in the early / middle or late stage of the declining phase. This ensures that all wells are in the same declining phase within the same assessment year. Wells with unstable production or a declining phase different from other wells within the same year are classified separately. For reservoirs with a small number of producing wells or complex production characteristics, an assessment can be conducted annually. Subsequently, each well is further classified according to the actual production years and the assessment year.

[0151] Based on the reservoir intervention planning and production dynamic analysis, different outcomes under different schemes are predicted. This requires conducting production dynamic analysis on the studied reservoir to screen wells that may undergo future reservoir interventions. Specifically, this includes production wells with a current water cut greater than 70%, multiple small layers developed, or long vertical perforation lengths, which may have the potential for water shut-off; production wells with long production times, multiple declining segments with different patterns, and each declining segment showing a significant increase in the decline rate Di or a decrease in the b-value, possibly due to an increase in the bottomhole skin coefficient, indicating potential acidization; and wells whose future production characteristics may deteriorate, specifically including wells that currently have no water or low water cut, with production characteristics indicating the water drive front is about to reach production, and a potential rapid increase in water cut; production wells with continuously decreasing formation pressure, which, based on the current downward trend, may lead to insufficient formation pressure in the future; and production wells with geological characteristics indicating the possibility of sand production.

[0152] For production wells with the potential for future water shut-off, numerical simulation is used to predict the production characteristics after water shut-off, replacing the current declining production prediction as the high-stakes prediction result. If no numerical simulation study is conducted, the changes in initial production, decline rate, and b-value before and after water shut-off can be compared with those of production wells in the same or similar reservoirs with similar reservoir conditions. If no comparable object is available, the same decline rate and b-value can be used, assuming that the production will increase to the level before water breakthrough, to predict the decline pattern after water shut-off.

[0153] For production wells with the potential for future acidizing, numerical simulation is used to predict the production characteristics after acidizing, replacing the current declining production predictions as the high-stakes prediction results. If no numerical simulation study is conducted, the changes in initial production, decline rate, and b-value before and after acidizing in production wells with similar reservoir conditions or similar reservoirs can be compared to predict the same proportions. If no comparable object is available, the decline rules Di and b of the first decline segment can be used, and the current production rate can still be used as the initial decline production rate to predict the decline rules after acidizing.

[0154] For wells where the water drive front is about to reach production, numerical simulation is used to predict the production characteristics after water breakthrough, replacing the current declining production prediction as the low-stakes prediction result. If no numerical simulation study is conducted, the change ratio of the decline rate and b-value after water breakthrough in production wells in the same or similar reservoirs with similar reservoir conditions can be used to make the same proportion change. If there is no comparable object, the decline rate after water breakthrough can be predicted by reducing b in the decline law to 0.

[0155] For production wells with continuously decreasing formation pressure, numerical simulation can be used to predict the production characteristics after the pressure drops to the abandonment pressure, replacing the current declining production prediction characteristics as the low-stakes prediction result. If no numerical simulation study has been conducted, the decline rate and b-value of production wells after the pressure drops to the abandonment pressure can be compared with the changes in the same proportion in reservoirs with similar reservoir conditions or similar reservoirs. If there is no comparable object, the decline rate and b-value in the decline law can be reduced to 0 to predict the decline law after the pressure drops to the abandonment pressure.

[0156] This disclosure provides a method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, comprising: first, determining the prediction frequency of recoverable reserves of the oil and gas reservoir based on the production stability of the production wells; next, predicting the production loss of the production wells based on historical production impact data and future production impact data; determining the corresponding production capacity parameters based on the current actual production and production loss of the production wells according to the current prediction frequency and well type; and finally, predicting the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the oil and gas reservoir and the future drilling sequence.

[0157] This disclosure further reduces output changes caused by factors such as artificial production restrictions and short-term measures by introducing output loss parameters, thereby improving the accuracy of output forecasting. At the same time, it conducts uncertainty analysis on the output forecast results, analyzes possible future scenarios, makes forecasts for each scenario, obtains output forecast results under various possibilities, and finally obtains different output forecasting schemes.

[0158] Example 5

[0159] To further illustrate the solution, based on the above embodiments, this embodiment takes offshore reservoir A as an example, see [link to example]. Figure 4 as well as Figure 5 This paper provides an application example to further explain a method for predicting recoverable reserves of oil and gas reservoirs based on uncertainties.

[0160] The purpose of this disclosure is to more accurately predict the recoverable reserves of oil reservoirs, and to obtain different schemes for predicting recoverable reserves based on possible future scenarios.

[0161] S1: Based on the overall dynamic analysis results of the reservoir, existing production wells are classified and their prediction frequencies are determined.

[0162] Specifically, wells are primarily classified into three types based on their well shape: vertical wells, deviated wells, and horizontal wells. For reservoirs where dynamic analysis shows little difference between deviated and horizontal wells, they can be classified into two types: vertical wells and deviated wells.

[0163] Specifically, for each well type, the assessment year is rationally divided based on the actual production situation of each well, considering factors such as production stability, whether it is in a declining phase, and whether it is in the early / middle or late stage of the declining phase. This ensures that all wells are in the same declining phase within the same assessment year. Wells with unstable production or a declining phase different from other wells within the same year are classified separately. For reservoirs with a small number of producing wells or complex production characteristics, an annual assessment can be conducted. Subsequently, each well is further classified according to the actual production years and the assessment year.

[0164] Statistical analysis of actual production data from Reservoir A shows that it began production in 2018 and currently has 29 producing wells, all of which are directional wells. Therefore, it is only necessary to divide the wells into assessment years and classify them accordingly. Considering that Reservoir A is developed offshore and adopts a strategy of high production with few wells and rapid extraction, the production wells enter the decline phase and the decline pattern changes rapidly. Therefore, wells entering the decline phase are classified annually based on the year they started production.

[0165] S2: Statistically analyze the production losses caused by human factors such as well repair, well shutdown, and production restrictions in each historical month, and predict future production losses based on the historical production loss trend and in combination with possible future scheduled well repair, well shutdown, and production restrictions.

[0166] Specifically, while predicting the production loss of each well, the possibility of future increases or decreases in production loss is analyzed based on historical well workover, well shut-in, production restriction characteristics, and depreciation of other reservoir equipment. Based on experience and actual changes in other reservoirs, different production loss values ​​are given.

[0167] See Figure 6 The on-site statistical parameter for reservoir A is production efficiency, which is numerically (1 - production loss). Therefore, based on the historical trend of production efficiency changes, the average value of the past four years (97%), which has remained relatively stable, is taken as the production efficiency for the next few years, i.e., a production loss of 3%. However, considering that with the aging of equipment over time, the production loss may not be able to maintain 3% in the long term, and taking the actual production characteristics of other surrounding reservoirs as a reference, the following options are selected: a high scenario where the production loss increases to 5% after 5 years; a medium scenario where the production loss increases to 5% after 3 years; and a low scenario where the production loss increases to 10% after 3 years.

[0168] S3: For each type of production well identified in step S1, calculate the IPC of that type by summing the actual output and the output loss, and use the IPC to predict the output respectively.

[0169] Specifically, for the identified stable production wells, the analogy method is used to refer to old wells with similar reservoir conditions in the same or similar reservoirs for prediction.

[0170] Specifically, for production wells with a steady decline in monthly production capacity (IPC), the production decline method is used to predict the production of each well separately, or the production wells of this type are predicted as a whole.

[0171] Specifically, for production wells with unstable monthly production capacity (IPC), the analogy method is used to refer to stable declining production wells in the same or similar reservoirs for prediction.

[0172] Specifically, for new wells with short operating times and unclear decline patterns, predictions can be made by referring to the production patterns of new wells in the same reservoir in the past, or by using the analogy method to refer to old wells in the same or similar reservoirs with similar reservoir conditions.

[0173] Specifically, while analyzing the decline patterns of various production wells, and combining reservoir management planning and production dynamics analysis, we predict possible future decline rate changes, and use the different decline rate prediction results as prediction results for different schemes.

[0174] See Figure 7 According to step S3, the well production decline rate in 2018 was 3.7%; the well production decline rate in 2019 was 1.2%; and wells that did not enter the decline phase after 2020 were predicted using the analogy method.

[0175] S4: For wells to be drilled in the future, the numerical simulation results during the drilling design will be used as the basic scheme prediction results. At the same time, the differences between the historical production effect of new wells and the prediction results will be considered, and the production allocation and decline rate of different new wells will be optimized as the prediction results of different schemes.

[0176] Based on the latest drilling sequence, the commissioning time of new wells not yet in production is determined. The numerical simulation results during drilling design are used as the prediction results of the basic scheme. Considering that the commissioning time of new wells in the past two years has been slower than the expected drilling sequence, and the initial production after commissioning has been lower than the predicted results, the following schemes are selected: Low scheme: new well commissioning is delayed by 2 months, and the initial production after commissioning is 80% of the design value; Medium scheme: new well commissioning is delayed by 1 month, and the initial production after commissioning is 80% of the design value; High scheme: new well commissioning is delayed by 1 month, and the initial production after commissioning is 100% of the design value.

[0177] S5: Add the predicted recoverable reserves of various production wells and the predicted recoverable reserves of wells to be drilled for each scheme to obtain the final prediction result for each scheme.

[0178] The production forecasts for each type of production well and the production forecasts for the wells to be drilled under each scheme are added together to obtain the final predicted cumulative recoverable reserves of reservoir A: 431 mmb for the low scheme, 576 mmb for the medium scheme, and 646 mmb for the high scheme.

[0179] As described above, the application example of this disclosure provides a method for predicting the recoverable reserves of oil and gas reservoirs based on uncertain factors. First, the prediction frequency of the recoverable reserves of the oil and gas reservoir is determined based on the production stability of the production wells. Next, the production loss of the production wells is predicted based on the historical production impact data and future production impact data. According to the current prediction frequency and well type, the corresponding production capacity parameters are determined based on the current actual production and production loss of the production wells. Finally, the recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all production wells in the oil and gas reservoir and the future drilling sequence.

[0180] The method for predicting recoverable reserves of oil and gas reservoirs that considers production uncertainty, as disclosed in this paper, can obtain different prediction schemes for recoverable reserves based on possible future scenarios, while accurately predicting the recoverable reserves of oil reservoirs.

[0181] Example 6

[0182] Based on the same inventive concept, this application also provides an apparatus for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, which can be used to implement the method described in the above embodiments, as shown in the following embodiments. Since the principle of the apparatus for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors is similar to that of the method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, the implementation of the apparatus for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors can refer to the implementation of the method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, and will not be repeated. As used below, the terms "unit" or "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the system described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0183] This invention provides a specific implementation of an apparatus for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, capable of implementing a method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors. See also... Figure 8 A device for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors includes:

[0184] The prediction frequency determination module 10 is used to determine the prediction frequency of the recoverable reserves of the oil and gas reservoir based on the production stability of the production wells in the oil and gas reservoir.

[0185] The production loss prediction module 20 is used to predict the production loss of the production well based on the historical production impact data and future production impact data of the production well.

[0186] The production capacity parameter determination module 30 is used to determine the corresponding production capacity parameters based on the current actual output of the production well and the output loss, according to the current prediction frequency and well type.

[0187] The recoverable reserves prediction module 40 is used to predict the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the oil and gas reservoir and the future drilling sequence.

[0188] In some embodiments of this disclosure, the production stability of the production well includes: an increasing production state, a stable production state, and a decreasing production state; wherein the decreasing state includes: an early decreasing state, a middle decreasing state, and a late decreasing state.

[0189] In some embodiments of this disclosure, when the production stability of the production well is in a decreasing state, the recoverable reserves of the oil and gas reservoir are predicted once a year.

[0190] In some embodiments of this disclosure, the historical production impact data includes: well workover, well shut-in, and production restriction;

[0191] The data on future production impacts include: anticipated well workovers, well shutdowns, production cuts, and equipment depreciation.

[0192] In some embodiments of this disclosure, the production capacity parameter determination module includes:

[0193] A production capacity parameter determination unit is used to determine the production capacity parameters of all production wells of each well type based on the current actual output of the production wells and the output loss at the current prediction frequency; wherein the output stability of multiple production wells corresponding to the current prediction frequency is the same.

[0194] In some embodiments of this disclosure, the recoverable reserves prediction module includes:

[0195] The production decline rate prediction unit is used to predict the future production decline rate of production wells of the corresponding well type based on the production capacity parameters.

[0196] A recoverable reserves prediction unit is used to predict the recoverable reserves of the oil and gas reservoir based on the production decline rate and the future drilling sequence.

[0197] This disclosure provides an apparatus for predicting recoverable reserves of an oil and gas reservoir based on uncertain factors, comprising: a prediction frequency determination module for determining the prediction frequency of recoverable reserves of the oil and gas reservoir based on the production stability of the production wells; a production loss prediction module for predicting the production loss of the production wells based on historical production impact data and future production impact data; a production capacity parameter determination module for determining the corresponding production capacity parameters based on the current actual production and production loss of the production wells according to the current prediction frequency and well type; and a recoverable reserves prediction module for predicting the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the oil and gas reservoir and the future drilling sequence.

[0198] In summary, the oil and gas reservoir recoverable reserve prediction device based on uncertain factors provided in this disclosure improves the prediction accuracy of various production well decline patterns by introducing production loss. At the same time, by analyzing the uncertainties that may occur in the future of key parameters, different schemes for recoverable reserve prediction are obtained, which can be effectively applied to various oil and gas reservoirs.

[0199] Example 7

[0200] Based on the above embodiments, this embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in the above embodiments.

[0201] In some embodiments of this example, a computer-readable storage medium is provided, on which a computer program is stored. When executed by a processor, the computer program implements the steps of the method described in the above embodiments, specifically including the following:

[0202] The frequency of predicting the recoverable reserves of an oil and gas reservoir is determined based on the production stability of its production wells.

[0203] The production loss of the production well is predicted based on the historical production impact data and future production impact data of the production well;

[0204] Based on the current forecast frequency and well type, determine the corresponding production capacity parameters according to the current actual output of the production well and the output loss.

[0205] The recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all producing wells and the future drilling sequence.

[0206] In some embodiments of this disclosure, the production stability of the production well includes: an increasing production state, a stable production state, and a decreasing production state; wherein the decreasing state includes: an early decreasing state, a middle decreasing state, and a late decreasing state.

[0207] In some embodiments of this disclosure, when the production stability of the production well is in a decreasing state, the recoverable reserves of the oil and gas reservoir are predicted once a year.

[0208] In some embodiments of this disclosure, the historical production impact data includes: well workover, well shut-in, and production restriction;

[0209] The data on future production impacts include: anticipated well workovers, well shutdowns, production cuts, and equipment depreciation.

[0210] In some embodiments of this disclosure, determining the corresponding production capacity parameters based on the current actual production of the production well and the production loss, according to the current prediction frequency and well type, includes:

[0211] At the current prediction frequency, the production capacity parameters of all production wells of each well type are determined based on the current actual production of the production wells and the production loss; wherein, the production stability of multiple production wells corresponding to the current prediction frequency is the same.

[0212] In some embodiments of this disclosure, the recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all producing wells and the future drilling sequence, including:

[0213] Predict the future production decline rate of production wells of the corresponding well type based on the aforementioned production capacity parameters;

[0214] The recoverable reserves of the oil and gas reservoir are predicted based on the production decline rate and the future drilling sequence.

[0215] In some embodiments of this example, a computer program product is provided, including a computer program / instructions, which, when executed by a processor, implements the steps of the method described in the above embodiments, specifically including the following:

[0216] The frequency of predicting the recoverable reserves of an oil and gas reservoir is determined based on the production stability of its production wells.

[0217] The production loss of the production well is predicted based on the historical production impact data and future production impact data of the production well;

[0218] Based on the current forecast frequency and well type, determine the corresponding production capacity parameters according to the current actual output of the production well and the output loss.

[0219] The recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all producing wells and the future drilling sequence.

[0220] In some embodiments of this disclosure, the production stability of the production well includes: an increasing production state, a stable production state, and a decreasing production state; wherein the decreasing state includes: an early decreasing state, a middle decreasing state, and a late decreasing state.

[0221] In some embodiments of this disclosure, when the production stability of the production well is in a decreasing state, the recoverable reserves of the oil and gas reservoir are predicted once a year.

[0222] In some embodiments of this disclosure, the historical production impact data includes: well workover, well shut-in, and production restriction;

[0223] The data on future production impacts include: anticipated well workovers, well shutdowns, production cuts, and equipment depreciation.

[0224] In some embodiments of this disclosure, determining the corresponding production capacity parameters based on the current actual production of the production well and the production loss, according to the current prediction frequency and well type, includes:

[0225] At the current prediction frequency, the production capacity parameters of all production wells of each well type are determined based on the current actual production of the production wells and the production loss; wherein, the production stability of multiple production wells corresponding to the current prediction frequency is the same.

[0226] In some embodiments of this disclosure, the recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all producing wells and the future drilling sequence, including:

[0227] Predict the future production decline rate of production wells of the corresponding well type based on the aforementioned production capacity parameters;

[0228] The recoverable reserves of the oil and gas reservoir are predicted based on the production decline rate and the future drilling sequence.

[0229] The processor may include, but is not limited to, one or more processors or microprocessors. Each processor may be implemented as an Application Specific Integrated Circuit (ASIC), Digital Signal Processor (DSP), Digital Signal Processing Device (DSPD), Programmable Logic Device (PLD), Field Programmable Gate Array (FPGA), controller, microcontroller, microprocessor, or other electronic component, for executing the methods in the above embodiments.

[0230] Computer-readable storage media can be implemented by any type of volatile or non-volatile storage device or a combination thereof. Computer-readable storage media may include, but are not limited to, random access memory (RAM), read-only memory (ROM), flash memory, EPROM memory, EEPROM memory, registers, and computer storage media (e.g., hard disks, floppy disks, solid-state drives, removable disks, CD-ROMs, DVD-ROMs, Blu-ray discs, etc.).

[0231] Computer-readable storage media may also store at least one computer-executable program / instruction, such as computer-readable instructions. Computer-readable storage media include, but are not limited to, volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Computer-readable storage media may include, for example, read-only memory (ROM), hard disk, flash memory, etc. For example, a non-transitory computer-readable storage medium may be connected to a computing device such as a computer, and then, when the computing device executes the computer-readable instructions stored on the computer-readable storage medium, the various methods described above can be performed.

[0232] In addition, the computer device may include (but is not limited to) a data bus, an input / output (I / O) bus, a display, and input / output devices (e.g., keyboard, mouse, speakers, etc.).

[0233] The processor can communicate with external devices via the I / O bus through wired or wireless networks.

[0234] In one embodiment, the at least one computer-executable instruction may also be compiled into or comprise a software product / computer program product, wherein one or more computer-executable instructions are executed by a processor to perform the steps of the various functions and / or methods in the embodiments described herein.

[0235] In the embodiments provided in this disclosure, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0236] It should be noted that, in this disclosure, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element limited by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0237] While the embodiments disclosed herein are as described above, the foregoing content is merely for the purpose of facilitating understanding of this disclosure and is not intended to limit this disclosure. Any person skilled in the art to which this disclosure pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope of this disclosure; however, the scope of patent protection of this disclosure shall still be determined by the scope defined in the appended claims.

Claims

1. A method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, characterized in that, include: The frequency of predicting the recoverable reserves of an oil and gas reservoir is determined based on the production stability of its production wells. The production loss of the production well is predicted based on the historical production impact data and future production impact data of the production well; Based on the current forecast frequency and well type, determine the corresponding production capacity parameters according to the current actual output of the production well and the output loss. The recoverable reserves of the oil and gas reservoir are predicted based on the production capacity parameters of all producing wells and the future drilling sequence.

2. The method for predicting recoverable reserves of oil and gas reservoirs according to claim 1, characterized in that, The production stability of the production well includes: an increasing production state, a stable production state, and a decreasing production state; wherein, the decreasing state includes: the early stage of the decreasing state, the middle stage of the decreasing state, and the late stage of the decreasing state.

3. The method for predicting recoverable reserves of oil and gas reservoirs according to claim 2, characterized in that, When the production stability of the production well is in a decreasing state, the recoverable reserves of the oil and gas reservoir are predicted once a year.

4. The method for predicting recoverable reserves of oil and gas reservoirs according to claim 1, characterized in that, The historical production impact data includes: well workovers, well shut-ins, and production restrictions; The data on future production impacts include: anticipated well workovers, well shut-ins, production cuts, and equipment depreciation.

5. The method for predicting recoverable reserves of oil and gas reservoirs according to any one of claims 1 to 4, characterized in that, The step of determining the corresponding production capacity parameters based on the current actual production of the production well and the production loss, according to the current prediction frequency and well type, includes: At the current prediction frequency, the production capacity parameters of all production wells of each well type are determined based on the current actual production of the production wells and the production loss; wherein, the production stability of multiple production wells corresponding to the current prediction frequency is the same.

6. The method for predicting recoverable reserves of oil and gas reservoirs according to claim 1, characterized in that, Based on the production capacity parameters of all producing wells in the oil and gas reservoir and the future drilling sequence, the recoverable reserves of the oil and gas reservoir are predicted, including: Predict the future production decline rate of production wells of the corresponding well type based on the aforementioned production capacity parameters; The recoverable reserves of the oil and gas reservoir are predicted based on the production decline rate and the future drilling sequence.

7. A device for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors, characterized in that, include: The prediction frequency determination module is used to determine the prediction frequency of the recoverable reserves of the oil and gas reservoir based on the production stability of the production wells in the oil and gas reservoir. The production loss prediction module is used to predict the production loss of the production well based on the historical production impact data and future production impact data of the production well. The production capacity parameter determination module is used to determine the corresponding production capacity parameters based on the current actual output of the production well and the output loss, according to the current prediction frequency and well type. The recoverable reserves prediction module is used to predict the recoverable reserves of the oil and gas reservoir based on the production capacity parameters of all production wells in the reservoir and the future drilling sequence.

8. A computer device, comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the method for predicting recoverable oil and gas reservoir reserves based on uncertain factors as described in any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the steps of the method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the steps of the method for predicting recoverable reserves of oil and gas reservoirs based on uncertain factors as described in any one of claims 1 to 6.

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