CN-116774294-B - Fluid identification method and system by saturated hydrogen index comparison method

CN116774294BCN 116774294 BCN116774294 BCN 116774294BCN-116774294-B

Abstract

The invention discloses a fluid identification method and a fluid identification system for a full-water hydrogen index contrast method, which are used for calculating porosity of a reservoir matrix, calculating porosity of rock cracks by combining electric imaging with bilateral data, summing total porosity with the porosity of the matrix, assuming full-water of the porosity of the reservoir matrix, selecting dynamic skeleton intermediate values of a compact layer section with the lowest porosity and high resistivity as fixed skeleton values, calculating intermediate values of a target layer dynamic skeleton by combining the total porosity, calculating the full-water hydrogen index of a research layer section according to the intermediate values of the dynamic skeleton, comparing the full-water hydrogen index with an actual neutron logging value to calculate neutron difference value, and analyzing the change relation between acoustic wave time difference and neutron difference value and the porosity of the matrix and neutron difference value by utilizing the neutron difference value to obtain a relation chart for quantitatively identifying a gas-water layer. The method removes the influence of anisotropy, crack occurrence and the like of bedrock lithology, highlights the characteristics of reservoir gas layers, and can more accurately identify the properties of reservoir fluids.

Inventors

LI NA
HAN XUE
WU YOUBIN
WANG ZHONGDONG
ZHANG XIAOWEI
GUO YI
YANG YUHANG
WANG HUIBO
ZHANG HAINING
LIU CHUNLEI
LI JUN
SUI XIUYING
GAO YANWU
TIAN CONGCONG
ZHANG CHENGEN
XU YONGFA

Assignees

中国石油天然气股份有限公司
中国石油集团测井有限公司

Dates

Publication Date: 20260512
Application Date: 20220311

Claims (8)

1.A method of fluid identification by comparison of a saturated hydrogen index, comprising the steps of: Acquiring the porosity of a reservoir matrix in a research work area, acquiring the porosity of a rock crack according to the porosity of the matrix, the electric imaging and the bilateral data, and acquiring the total porosity of the rock according to the porosity of the rock crack and the porosity of the matrix; obtaining a target layer dynamic skeleton sub-value according to the rock physical volume model and the total porosity of the rock; Acquiring a saturated water hydrogen index of the research interval according to the dynamic skeleton intermediate value and the petrophysical volume model; Comparing the hydrogen index saturated with water with the actual neutron logging value to obtain a neutron difference value; Analyzing the change relation between the acoustic wave time difference and the neutron difference value and the change relation between the matrix porosity and the neutron difference value by combining the gas test and the neutron difference value to obtain a relation chart for quantitatively identifying a gas-water layer; The method for obtaining the porosity of the rock cracks and the total porosity of the rock comprises the following steps of calculating the porosity of the rock cracks by a crack density calibration coring section electric imaging logging crack pick-up method described by a rock core; target layer dynamic skeleton intermediate value Is calculated as formula Wherein, the method comprises the steps of, The dynamic skeleton is a child value, and the unit is; is the theoretical hydrogen index of water, in units of, Is the total porosity of the rock.
2. The fluid identification method of saturated aqueous hydrogen index contrast of claim 1, wherein the calculation method of studying reservoir matrix porosity in a work area comprises the steps of: Determining the mineral percentage of each mineral in the reservoir rock; Multiplying the mineral percentage content of each mineral by the mineral theoretical acoustic wave value corresponding to the mineral and summing to obtain a rock matrix mineral skeleton acoustic wave time difference value; bringing the difference value of the acoustic wave of the mineral skeleton of the rock matrix into a rock physical volume model to obtain the porosity of the matrix; Porosity of the matrix The calculation of (2) is shown in the formula (1): (1) Wherein, the The porosity of the matrix is expressed in units of; the unit is us/ft which is the difference value of logging sound waves; is the difference in fluid acoustic wave time in us/ft; The difference in acoustic wave time is expressed as us/ft for the mineral framework of the rock matrix.
3. The fluid identification method of saturated aqueous hydrogen index contrast of claim 1, wherein dynamic skeletal mesovalues of the dense interval are selected as fixed skeletal values 。
4. The fluid identification method of saturated aqueous hydrogen index contrast of claim 1, wherein the interval saturated aqueous hydrogen index is studied The calculation of (2) is shown in the formula (3): (3) Wherein, the Is the total porosity of the rock and, Is the porosity of the stratum water neutrons, Is a seed value in the rock dynamic skeleton.
5. The fluid identification method of saturated aqueous hydrogen index contrast of claim 4, wherein the neutron difference value The calculation of (2) is shown in formula (4): (4) Wherein, the Is the actual well logging value of neutrons.
6. A system employing the fluid identification method of the hydrogen saturation index contrast method of any one of claims 1 to 5, comprising: The porosity acquisition module is used for acquiring the porosity of the reservoir matrix in the research work area, acquiring the porosity of the rock fracture according to the porosity of the matrix, the electric imaging and the bilateral data, and acquiring the total porosity of the rock according to the porosity of the rock fracture and the porosity of the matrix; the dynamic skeleton neutron value acquisition module is used for acquiring a target layer dynamic skeleton neutron value according to the rock physical volume model and the total porosity of the rock; The saturated water hydrogen index acquisition module is used for acquiring the saturated water hydrogen index of the research layer section according to the sub-value in the dynamic skeleton and the petrophysical volume model; The neutron difference value acquisition module is used for comparing the saturated water hydrogen index with the neutron actual logging value to acquire a neutron difference value; And the gas-water layer relation chart acquisition module is used for combining the gas test data and the neutron difference value, analyzing the change relation between the acoustic wave time difference and the neutron difference value and between the matrix porosity and the neutron difference value, and acquiring the relation chart for quantitatively identifying the gas-water layer.
7. A computer device comprising a memory and a processor, said memory storing a computer program, characterized in that, the processor, when executing a computer program, performs the steps of the fluid identification method of the hydrogen saturation index contrast method of any one of claims 1 to 5.
8. A computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the steps of the fluid identification method of the hydrogen saturation index contrast method of any one of claims 1 to 5.

Description

Fluid identification method and system by saturated hydrogen index comparison method Technical Field The invention belongs to the field of reservoir fluid property evaluation, and relates to a fluid identification method and system by a saturated hydrogen index comparison method. Background The gas layer identification method mainly comprises a three-porosity intersection method, a three-porosity difference ratio method, an aspect ratio method, a apparent elastic modulus coefficient method, a nuclear magnetic difference spectrum method, a shift spectrum method and the like. As most of the reservoirs in the prior oil fields have the characteristics of complex lithology, low pore hypotonic property, low maturity, strong heterogeneity, complex pore structure and the like. The signals that result in the properties of the resistivity-reactive fluid are weak, and it is difficult to accurately discern the reservoir gas content, and there is a strong need for a method for forming an electrically non-effective gas layer identification. Disclosure of Invention The invention aims to solve the problems in the prior art, provides a fluid identification method and a fluid identification system for a saturated hydrogen index comparison method, and aims to solve the technical problems that the signals of resistivity reaction fluid properties are weak, and the defect that the reservoir gas-containing property is difficult to accurately distinguish in the prior art. In order to achieve the purpose, the invention is realized by adopting the following technical scheme: The invention provides a fluid identification method of a saturated hydrogen index comparison method, which is characterized by comprising the following steps of: Acquiring the porosity of a reservoir matrix in a research work area, acquiring the porosity of a rock crack according to the porosity of the matrix, the electric imaging and the bilateral data, and acquiring the total porosity of the rock according to the porosity of the rock crack and the porosity of the matrix; obtaining a target layer dynamic skeleton sub-value according to the rock physical volume model and the total porosity of the rock; Acquiring a saturated water hydrogen index of the research interval according to the dynamic skeleton intermediate value and the petrophysical volume model; Comparing the hydrogen index saturated with water with the actual neutron logging value to obtain a neutron difference value; And analyzing the change relation between the acoustic wave time difference and the neutron difference and between the matrix porosity and the neutron difference by combining the gas test and the neutron difference to obtain a relation chart for quantitatively identifying the gas-water layer. Preferably, the method of calculating porosity of a reservoir matrix in a research work area comprises the steps of: Determining the mineral percentage of each mineral in the reservoir rock; Multiplying the mineral percentage content of each mineral by the mineral theoretical acoustic wave value corresponding to the mineral and summing to obtain a rock matrix mineral skeleton acoustic wave time difference value; Bringing the difference value of the acoustic wave of the mineral skeleton of the rock matrix into a rock physical volume model to obtain the porosity of the matrix, wherein the calculation of the porosity phi Substrate of the matrix is shown as a formula (1): wherein phi Substrate is the matrix porosity in units of%Deltat Measurement of is the difference in units of us/ft in the case of logging sound waves, deltat Fluid body is the difference in units of us/ft in the case of fluid sound waves, and Deltat Mixing ma is the difference in units of us/ft in the case of rock matrix mineral skeleton sound waves. Preferably, the rock fracture porosity and the total porosity of the rock are obtained as follows: Calculating the porosity of the rock cracks by using a crack density calibration coring section electric imaging logging crack pick-up method described by the rock core; and summing the porosity of the rock cracks and the porosity of the matrix to obtain the total porosity of the rock. Preferably, the destination layer dynamic skeleton is a child valueThe calculation of (2) is as shown in formula (2): Wherein, the The dynamic skeleton is a child value, and the unit is; Is the theoretical hydrogen index of water, in units of, Is the total porosity of the rock. Preferably, dynamic skeleton mid-values of the dense interval are selected as fixed skeleton values Preferably, the interval saturation hydrogen index is studiedThe calculation of (2) is shown in the formula (3): Wherein, the Is the total porosity of the rock and,Is the porosity of the stratum water neutrons,Is a seed value in the rock dynamic skeleton. Preferably, neutron differenceThe calculation of (2) is shown in formula (4): Wherein, the Is the actual well logging value of neutrons. The invention provides a system for