CN-121996866-A - Fracture-cavity type carbonate reservoir dynamic reserve calculation method, calculation system and equipment

CN121996866ACN 121996866 ACN121996866 ACN 121996866ACN-121996866-A

Abstract

The invention provides a fracture-cavity type carbonate reservoir dynamic reserve calculation method, a calculation system and equipment, which comprise the steps of calculating and obtaining crude oil calculation parameters based on reservoir fluid property data, screening obtained oil well production data in a self-injection period based on obtained bubble point pressure to obtain historical cumulative pressure drop and historical cumulative oil, constructing and obtaining dynamic reserve characteristics based on the historical cumulative pressure drop data and the historical cumulative oil data, obtaining a current production curve based on fitting current cumulative oil pressure drop data and current cumulative oil data in a well opening production process after well-round water injection is obtained, obtaining elastic yield based on fitting of the current production curve, and calculating dynamic reserves of holes, seams and holes based on dynamic reserve characteristics reacted in the self-injection period and water injection oil replacement stage.

Inventors

YUAN XIAOMAN
ZHANG JIE
WANG HUAILONG
LU ZHONGYUAN
TIAN XINJIAN
WANG PENG
LIANG RUIHAN
LIU ZIWEI
Elishati Kudi

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241107

Claims (10)

1. The calculation method of the dynamic reserves of the fracture-cavity type carbonate reservoir is characterized by comprising the following steps of: Calculating crude oil calculation parameters based on reservoir fluid property data; Screening the obtained production data of the oil well in the self-injection period based on the obtained bubble point pressure to obtain historical cumulative pressure drop and historical cumulative oil, and constructing a characteristic type library based on the historical cumulative pressure drop data and the historical cumulative oil data; Fitting current accumulated oil pressure drop data and current accumulated oil production data in the well opening production process to obtain a current production curve based on the obtained oil well round water injection, and obtaining elastic yield based on the current production curve fitting; Determining dynamic reserve characteristics represented by the current production curve based on comparison of the characteristic type library with the current production curve; And respectively calculating the dynamic reserves of the holes, the seams and the holes based on the elastic yield, the crude oil calculation parameters and the dynamic reserve characteristics reflected in the self-injection period and the water injection oil-replacing stage.
2. The method of calculating dynamic reserves of a fracture-cavity carbonate reservoir of claim 1, wherein calculating the crude oil calculation parameters based on the reservoir fluid property data comprises: Obtaining a saturated oil pressure coefficient and a crude oil volume coefficient in an oil reservoir fluid property report of an open well or an adjacent well; obtaining a crude oil compression coefficient calculation formula based on saturated oil compression coefficient fitting, and obtaining a crude oil compression coefficient based on the obtained current stratum pressure value by using the crude oil compression coefficient calculation formula; and obtaining a crude oil volume coefficient calculation formula based on crude oil volume coefficient fitting, and obtaining the crude oil volume coefficient under the formation pressure by utilizing the crude oil volume coefficient calculation formula based on the obtained current formation pressure value.
3. The fracture-cavity type carbonate reservoir dynamic reserve calculation method according to claim 2, wherein the crude oil compression coefficient calculation formula is obtained based on saturated oil compression coefficient fitting, and comprises: Taking the saturated oil pressure coefficient as an ordinate, and taking a midpoint value of a stratum pressure range corresponding to the saturated oil pressure coefficient as an ordinate, fitting to obtain first coordinate point data; Fitting the first coordinate point data in a rectangular coordinate system to form a saturated oil compression coefficient curve; And calculating the fitting coefficient of each saturated oil compression coefficient curve, selecting a saturated oil compression coefficient curve with the fitting coefficient close to 1 as a crude oil compression coefficient fitting curve, and fitting to obtain a crude oil compression coefficient calculation formula.
4. The method for calculating the dynamic reserve of the fracture-cavity type carbonate reservoir according to claim 1, wherein the calculation formula for the crude oil volume coefficient is obtained based on fitting of the crude oil volume coefficient, and the calculation formula for the crude oil volume coefficient comprises the steps of fitting the crude oil volume coefficient with a midpoint value of a formation pressure range corresponding to the crude oil volume coefficient as an ordinate to obtain second coordinate point data; And fitting the second coordinate point data in a rectangular coordinate system to form a crude oil volume coefficient curve, and taking linear correlation to obtain a crude oil volume coefficient calculation formula.
5. The method for calculating dynamic reserves of a fracture-cavity carbonate reservoir according to claim 1, wherein obtaining the historical cumulative pressure drop and the historical cumulative oil based on the self-injection oil well production data obtained by the bubble point pressure screening comprises: And acquiring production data of the oil well in the self-injection period, comparing the oil pressure in the production data of the oil well in the self-injection period with the bubble point pressure, and reserving production cumulative pressure drop and production cumulative oil corresponding to the oil pressure greater than the bubble point pressure to obtain historical cumulative pressure drop and historical cumulative oil.
6. The method for calculating the dynamic reserves of the fracture-cavity type carbonate reservoir according to claim 1, wherein the constructing the characteristic type library based on the historical cumulative pressure drop data and the historical cumulative oil data comprises the following steps: Fitting based on the historical cumulative pressure drop data and the historical cumulative oil data to obtain a historical self-injection period characteristic curve; judging the linear relation of the characteristic curve of the historical self-spraying period; If the historical self-injection period characteristic curves are in a linear relationship, the historical self-injection period characteristic curves belong to the collective self-injection period characteristics of the cave and the hole type reservoir; if the historical self-injection period characteristic curve is in a nonlinear relation, representing that the far end of the reservoir body has liquid supply characteristics, and the characteristic of the reservoir body is a cave, a hole and a crack type reservoir body collective characteristic; And merging the collective features of the cave, the hole and the fracture type reservoir and the collective self-injection period features of the cave, the hole and the reservoir to obtain the feature type library.
7. The method for calculating the dynamic reserves of the fracture-cavity type carbonate reservoir according to claim 1, wherein the calculating process for calculating the dynamic reserves of the hole, the fracture and the cavity respectively based on the elastic yield, the crude oil calculating parameter and the dynamic reserves characteristics reflected by the self-injection period and the water injection and oil replacement stage comprises the following steps: ; Wherein, the M 3 is the current accumulated oil production; the volume coefficient of crude oil under formation pressure; Is a dynamic reserve; Is the volume coefficient under the original pressure; is the total compression coefficient of 1/MPa, wherein, The total pressure drop is MPa, , Original formation pressure-current formation pressure.
8. The method for calculating the dynamic reserves of the fracture-cavity type carbonate reservoir according to claim 7, wherein the calculating process for calculating the dynamic reserves of the hole, the fracture and the cavity respectively based on the elastic yield, the crude oil calculation parameters and the dynamic reserves characteristics reflected in the self-injection period and the water injection oil replacement period after the water injection of the oil well is as follows: ; Wherein, the Accumulated oil production m 3 for the ground; the volume coefficient of crude oil under formation pressure; Is a dynamic reserve; Is the volume coefficient under the original pressure; is 1/MPa of total compression coefficient; total pressure drop MPa; The compression coefficient of water and rock is 1/MPa; is the water volume coefficient under the original pressure; Is the seal water volume m 3 ; Accumulating water production for the ground; is the volume coefficient of water, and is equal to the volume coefficient of water, , Original formation pressure-current formation pressure; Total compression coefficient The calculation process of (1) is as follows: ; in the formula, Is the comprehensive compression coefficient; is the compression coefficient of crude oil; is the water compression coefficient; To irreducible water saturation; is the original oil saturation; is the rock compression coefficient.
9. The fracture-cavity type carbonate reservoir dynamic reserve calculation system is characterized in that the fracture-cavity type carbonate reservoir dynamic reserve calculation method based on any one of claims 1-8 comprises the following steps: The first processing unit is used for calculating crude oil calculation parameters based on the reservoir fluid property data; the characteristic processing unit is used for screening the acquired production data of the self-injection oil well based on the acquired bubble point pressure to obtain historical cumulative pressure drop and historical cumulative oil, and constructing a characteristic type library based on the historical cumulative pressure drop data and the historical cumulative oil data; the second processing unit is used for obtaining a current production curve based on fitting of current accumulated oil pressure drop data and current accumulated oil pressure data in the well opening production process after well wheel injection is obtained, and obtaining elastic yield based on fitting of the current production curve; The type judging unit is used for determining dynamic reserve characteristics represented by the current production curve based on comparison of the characteristic type library and the current production curve; The third processing unit is used for respectively calculating and obtaining the dynamic reserves of holes, slits and holes based on the elastic yield, the crude oil calculation parameters and the dynamic reserve characteristics reflected in the self-injection period and the water injection oil-replacement stage; And the output unit is used for outputting the calculated dynamic reserves of the holes, the slits and the holes.
10. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the computer program, carries out the steps of the method for calculating dynamic reserves of a fracture-cavity carbonate reservoir according to any one of claims 1 to 8.

Description

Fracture-cavity type carbonate reservoir dynamic reserve calculation method, calculation system and equipment Technical Field The invention belongs to the technical field of oil and gas reservoir development, and particularly relates to a calculation method, a calculation system and equipment for dynamic reserves of a fracture-cavity type carbonate reservoir. Background The fracture-cavity type carbonate reservoir has extremely strong heterogeneity, the reservoir space is mainly of three types of holes, cracks and holes, so that fluid distribution in the reservoir presents obvious separability, fluid flow characteristics are complex and changeable, the reservoir space, fluid distribution, oil-water interfaces and the like have various uncertainties, namely, the reservoir capacity of the holes and cavities is relatively strong, the fracture plays a role in communicating a plurality of reservoirs, has seepage-storing capacity, is an important seepage channel of fluid, further causes unclear knowledge of reservoir dynamic reserves, and brings great difficulty to calculation of the dynamic reserves. At present, the calculation of the dynamic reserves of the fracture-cavity type carbonate reservoir is mainly based on a calculation method of a material balance theory, wherein the method is based on divided fracture-cavity units, a single-well control area is determined by using a single-well recoverable reserve, then the single-well dynamic reserves are calculated by using a volumetric method, although the method can calculate the dynamic reserves in the single well, the single-well control area is gradually increased by the establishment of the single-well recoverable reserve along with the increase of drilling depth, and further the error of dynamic energy storage data obtained by calculation through the volumetric method is large, so that the development scheme is established in a non-conforming manner, and the development efficiency and economic benefit of the oil and gas reservoir are affected. Disclosure of Invention The invention provides a calculation method, a calculation system and equipment for the dynamic reserves of a fracture-cavity type carbonate reservoir, which are used for solving the problems of low development efficiency and high economic cost of the hydrocarbon reservoir caused by the fact that the error of the dynamic energy storage data obtained by calculation is greatly increased along with the increase of the development depth of the hydrocarbon reservoir. In order to achieve the above purpose, the present invention provides the following technical solutions: The invention provides a calculation method of dynamic reserves of a fracture-cavity carbonate reservoir, which comprises the following steps: Calculating crude oil calculation parameters based on reservoir fluid property data; Screening the obtained production data of the oil well in the self-injection period based on the obtained bubble point pressure to obtain historical cumulative pressure drop and historical cumulative oil, and constructing a characteristic type library based on the historical cumulative pressure drop data and the historical cumulative oil data; Fitting current accumulated oil pressure drop data and current accumulated oil production data in the well opening production process to obtain a current production curve based on the obtained oil well round water injection, and obtaining elastic yield based on the current production curve fitting; Determining dynamic reserve characteristics represented by the current production curve based on comparison of the characteristic type library with the current production curve; And respectively calculating the dynamic reserves of the holes, the seams and the holes based on the elastic yield, the crude oil calculation parameters and the dynamic reserve characteristics reflected in the self-injection period and the water injection oil-replacing stage. Preferably, the crude oil calculation parameters are calculated based on reservoir fluid property data, including: Obtaining a saturated oil pressure coefficient and a crude oil volume coefficient in an oil reservoir fluid property report of an open well or an adjacent well; obtaining a crude oil compression coefficient calculation formula based on saturated oil compression coefficient fitting, and obtaining a crude oil compression coefficient based on the obtained current stratum pressure value by using the crude oil compression coefficient calculation formula; and obtaining a crude oil volume coefficient calculation formula based on crude oil volume coefficient fitting, and obtaining the crude oil volume coefficient under the formation pressure by utilizing the crude oil volume coefficient calculation formula based on the obtained current formation pressure value. Preferably, the calculation formula of the crude oil compression coefficient based on the saturated oil compression coefficient fitting comprises the following steps: