CN103760081A - Gas pool prediction method and system of carbonate reservoir based on pore structure characteristics - Google Patents

Abstract

The invention provides a gas pool prediction method and system of a carbonate reservoir based on pore structure characteristics. The method comprises the following steps: collecting a rock sample of a target reservoir section of the carbonate reservoir; authenticating geological thin sheets of the rock sample so as to obtain rock basic parameters comprising the rock constituents, the pore shape, the surface porosity and the sedimentary phase belt; carrying out pore permeation measurement on the rock sample so as to obtain pore permeation basic parameters comprising the porosity, the permeation rate and the density; constructing a rock bare-bone model according to the rock basic parameters, the pore permeation basic parameters and a differential equivalent medium model; carrying out fluid replacement on the rock bare-bone model so as to generate a rock physical plate; acquiring prestack seismic inversion data of the carbonate reservoir; intersecting the prestack seismic inversion data and the rock physical plate, thereby obtaining the prediction results of the porosity and the gas saturation of the carbonate reservoir. The accurate quantitative gas pool prediction is realized.

Description

Gas reservoir Forecasting Methodology and the system of the carbonate reservoir based on pore structure characteristic

Technical field

The present invention, about oil-gas exploration technical field, particularly about the forecasting techniques of carbonate reservoir, is a kind of gas reservoir Forecasting Methodology and system of the carbonate reservoir based on pore structure characteristic concretely.

Background technology

According to USGS statistics in 2000, in global range, Marine Carbonate Rocks oil gas mining resources amount accounted for 72% of total oil gas mining resources amount, in leading position.Carbonatite oil and gas reserves to be verified is abundant more than petroclastic rock, and Exploration Potential is huge.Organic reef beach, as a kind of good carbonate reservoir, is the Focal point and difficult point of oil-gas exploration.

Carbonate reservoir complex pore structure, nonuniformity is strong, can have a huge impact seimic wave velocity.By research, find, the carbonate reservoir (such as hole hole, moldic pore, intergranular space, intergranular pore, intragranular pore etc.) of dividing by porosity type, speed reduces along with the increase of factor of porosity, but different porosity type does not show obvious regularity.Press the carbonate reservoir (such as acicular pores, flat hole, circular hole etc.) that pore texture is divided, speed reduces along with the increase of factor of porosity, and the velocity variations rule of different pore structures is obvious, the in the situation that of a given porosity value, speed difference can exceed 1500m/s.Therefore, the complicacy of carbonate reservoir pore texture can cause the greatest differences of rock elasticity feature, is a key factor that determines rock elasticity feature.

In the industrialization technology of petroleum exploration, the rock physics plate of the conventional gas-oil detecting method utilization based on rock physics analysis based on single pore morpholohy predicted the whole district, is mainly applicable to the reservoir that pore morpholohy is more single at present.Carbonate reservoir complex pore structure, nonuniformity is strong, and when reservoir pore space form horizontal change is remarkable, individual well rock physics is modeled in the whole district and has applicability problem.

Gassmann equation is at low frequency Imitating pore media elastic wave propagation, and when frequency is higher, the basis hypothesis of Gassmann equation is false, and can not describe the wave propagation in the pore media that comprises fluid.Biot has set up the basic motive theory of the elastic wave that comprises fluid rock, the essence of this theory is by the fluctuation characteristic that is full of fluid rock (speed and decay) and Rock Matrix, rock skeleton (dry rock) and fluid communication, is applicable to whole frequency range.The basic assumption of Biot theory comprises: the empty pore media of (1) rock (matrix and skeleton) is all even isotropic in macroscopic view; (2) all holes all interconnect, and particle size is just the same; (3) average-size of wavelength ratio rock particles is much bigger; (4) Darcy law is followed in the relative motion between Rock Matrix and pore fluid; (5) mutually there is not chemical action in pore fluid and Rock Matrix.Biot is theoretical when frequency goes to zero, basically identical with Gassmann equation.Thereafter in research, this theory is generalized to again anisotropic medium, but process is very complicated, and some are difficult to the parameter obtaining conventionally to require input, to such an extent as to there is no widespread use.

Traditional Biot-Gassmann theory is studied containing seismic wave propagation mechanism in the porous medium of fluid for hole, but main consideration is the homogeneous pore texture of saturated a kind of fluid, ignore the uneven distribution of mineralogical composition, solid particle, pore texture and the fluid components of rock interior, can not describe the complex situations of actual reservoir.The impact of the bubble that White etc. have analyzed the inner local distribution of waterstone on seismic wave propagation.Dutta etc. have improved White theory, and its velocity of longitudinal wave of predicting under low-frequency limit and classical Biot theoretical analysis result are matched.Johnson has proposed a kind of branch function method, has realized the simulation to unsaturated media ripple propagation law in different frequency range.M ü ller, Gurevich and Toms etc. think that the numerical simulation of one dimension and three-dimensional random unsaturated media also can provide rational description and prediction for the wave response of actual rock.Biot stream and the injection stream based on containing fluid rock interior such as Dvorkin, has proposed BISQ theory.Nie builds new grade and in BISQ model, has introduced the unsaturated situation of fluid.Nie Jianxin, Ba Jing etc. have studied the impact of fluid unsaturation on the medium wave propagation of BISQ model, but the supposed premise of this result is gas, water, completely evenly mix.Liu Jiong etc. have studied the seismic wave propagation rule in non-homogeneous, the unsaturated rock model that spherical patch and level replace stratiform, but calculate the loaded down with trivial details application that is unfavorable for.

In sum, in the scheme of prior art, mainly there is following problem:

(1) carbonate reservoir development area complex pore structure, in the whole district, there is applicability problem in the conventional petrophysical model based on single pore texture;

(2) carbonate reservoir nonuniformity is strong, and the conventional fluid substitution method mixing based on fluid well-distributing can not accurately be described the distribution of subsurface rock and fluid.

Summary of the invention

The problems referred to above that exist in order to overcome prior art, the invention provides a kind of gas reservoir Forecasting Methodology and system of the carbonate reservoir based on pore structure characteristic, the impact of petrophysical model being set up for carbonate reservoir rock pore structure, the different pore structures of growing for the different geology sedimentary facies belts of carbonatite, sets up respectively corresponding rock skeleton model; For the saturated situation of carbonate reservoir fluid section, by simulation hole homogeneous, the state of fluid non-uniform Distribution carries out fluid substitution, carries out accurate gas reservoir quantification prediction.

One of object of the present invention is, a kind of gas reservoir Forecasting Methodology of the carbonate reservoir based on pore structure characteristic is provided, and comprising: the rock specimens that gathers carbonate reservoir target reservoir section; Described rock specimens is carried out to the evaluation of geology thin slice, obtain rock basic parameter, described rock basic parameter comprises rock composition, pore shape, face rate and sedimentary facies belt; Described rock specimens is carried out to hole and ooze measurement, must arrive hole and ooze basic parameter, described hole is oozed basic parameter and is comprised factor of porosity, permeability and density; According to described pore shape and sedimentary facies belt, carry out pore Structure Analysis, according to described rock basic parameter, hole, ooze basic parameter and the dry skeleton pattern of differential EFFECTIVE MEDIUM model construction rock; The dry skeleton pattern of described rock is carried out to fluid substitution, generate rock physics plate; Obtain the pre-stack seismic inversion data of carbonate reservoir; Described pre-stack seismic inversion data and described rock physics plate are carried out to intersection, obtain the factor of porosity of described carbonate reservoir and predicting the outcome of gas saturation.

One of object of the present invention is, a kind of gas reservoir prognoses system of the carbonate reservoir based on pore structure characteristic is provided, and comprising: rock specimens harvester, for gathering the rock specimens of carbonate reservoir target reservoir section; Geology thin slice identification apparatus, carries out the evaluation of geology thin slice for the rock specimens to described, obtains rock basic parameter, and described rock basic parameter comprises rock composition, pore shape, face rate and sedimentary facies belt; Measurement mechanism is oozed in hole, carries out hole ooze measurement for the rock specimens to described, must arrive hole and ooze basic parameter, and described hole is oozed basic parameter and comprised factor of porosity, permeability and density; The dry skeleton member device of rock, for carrying out pore Structure Analysis according to described pore shape and sedimentary facies belt, oozes basic parameter and the dry skeleton pattern of differential EFFECTIVE MEDIUM model construction rock according to described rock basic parameter, hole; Rock physics plate generating apparatus, carries out fluid substitution for the dry skeleton pattern of the rock to described, generates rock physics plate; Pre-stack seismic inversion data acquisition facility, for obtaining the pre-stack seismic inversion data of carbonate reservoir; Gas saturation prediction unit, for described pre-stack seismic inversion data and described rock physics plate are carried out to intersection, obtains the factor of porosity of described carbonate reservoir and predicting the outcome of gas saturation.

Beneficial effect of the present invention is, a kind of gas reservoir Forecasting Methodology and system of the carbonate reservoir based on pore structure characteristic are provided, because carbonate reservoir nonuniformity is strong, rock physics modeling based on single pore texture can not take into account this nonuniformity preferably, for the modeling of carbonate reservoir rock physics and gas reservoir quantification forecasting problem, technical scheme of the present invention will solve the significant difficulties that prior art faces, and reaches following object:

1, take into full account the micropore structure of carbonate reservoir development area complexity, utilize the technological means such as the evaluation of geology thin slice and core experiment measurement, the division that is pore structure characteristic from geological analysis and experimental observation angle respectively provides foundation, and the different pore structures of growing for different sedimentary facies belts is set up respectively rock skeleton model.

2, the specific aim petrophysical model that analysis obtains based on pore structure characteristic, designs the fluid detection method of different sedimentary facies reservoirs.

For above and other object of the present invention, feature and advantage can be become apparent, preferred embodiment cited below particularly, and coordinate appended graphicly, be described in detail below.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.

The process flow diagram of the embodiment one of the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic that Fig. 1 provides for the embodiment of the present invention;

The process flow diagram of the embodiment two of the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic that Fig. 2 provides for the embodiment of the present invention;

The process flow diagram of the embodiment three of the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic that Fig. 3 provides for the embodiment of the present invention;

Fig. 4 is the particular flow sheet of the step S107 in Fig. 1;

The process flow diagram of the embodiment four of the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic that Fig. 5 provides for the embodiment of the present invention;

The structured flowchart of the embodiment one of the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Fig. 6 provides for the embodiment of the present invention;

The structured flowchart of the embodiment two of the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Fig. 7 provides for the embodiment of the present invention;

The structured flowchart of the embodiment three of the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Fig. 8 provides for the embodiment of the present invention;

The concrete structure block diagram of gas saturation prediction unit 700 in the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Fig. 9 provides for the embodiment of the present invention;

The structured flowchart of the embodiment four of the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Figure 10 provides for the embodiment of the present invention;

Figure 11 is Met22 well reservoir rock thin slice (dissolution pore) schematic diagram;

Figure 12 is Met21 well reservoir rock thin slice (crack) schematic diagram;

Figure 13 is the rock specimens schematic diagram of the carbonate reservoir target reservoir section of collection;

Figure 14 is the CT scan schematic diagram of the rock specimens of the carbonate reservoir target reservoir section of collection;

Figure 15 is factor of porosity and density relationship figure;

Figure 16 is factor of porosity and permeability graph of a relation;

Figure 17 is the schematic diagram of conventional ultrasound measuring system;

Figure 18 is the p-and s-wave velocity of rock under drying regime and the graph of a relation of factor of porosity;

Figure 19 is the p-and s-wave velocity of rock under water saturation state and the graph of a relation of factor of porosity;

Figure 20 is that core sample factor of porosity compares graph of a relation with p-and s-wave velocity;

Figure 21 is that core sample p-wave impedance compares graph of a relation with p-and s-wave velocity;

Figure 22 is the affect graph of a relation of reservoir rock pore texture on velocity of longitudinal wave;

Figure 23 is rock physics plate and the M22 well lie geological data X plot based on dissolution pore pore texture;

Figure 24 is rock physics plate and the M21 well lie geological data X plot based on fracture pore structure;

Figure 25 was Met22 and Met3 well two-dimensional line factor of porosity seismic inversion schematic diagram;

Figure 26 was Met22 and Met3 well two-dimensional line gas saturation seismic inversion schematic diagram;

Figure 27 is Met22 borehole logging tool porosity curve and gas testing interval schematic diagram;

Figure 28 is Met3 borehole logging tool porosity curve and gas testing interval schematic diagram;

Figure 29 was Zen21 and Met21 well two-dimensional line factor of porosity seismic inversion schematic diagram;

Figure 30 was Zen21 and Met21 well two-dimensional line gas saturation seismic inversion schematic diagram;

Figure 31 is Zen21 borehole logging tool porosity curve and gas testing interval schematic diagram;

Figure 32 is Met21 borehole logging tool porosity curve and gas testing interval schematic diagram.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Based on the embodiment in the present invention, those of ordinary skills, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.

Carbonate reservoir nonuniformity is strong, and the rock physics modeling based on single pore texture can not take into account this nonuniformity preferably.For the modeling of carbonate reservoir rock physics and gas reservoir quantification forecasting problem, gas reservoir Forecasting Methodology and the system of a kind of carbonate reservoir based on pore structure characteristic that the present invention proposes, Fig. 1 is the particular flow sheet of the method, and as shown in Figure 1, described method comprises:

S101: the rock specimens that gathers carbonate reservoir target reservoir section.In concrete embodiment, can adopt conventional method of seismic prospecting to gather the rock specimens of carbonate reservoir target reservoir section.

S102: described rock specimens is carried out to the evaluation of geology thin slice, obtain rock basic parameter, described rock basic parameter comprises rock composition, pore shape, face rate and sedimentary facies belt.It is the method for identifying rocks and minerals under polarizing microscope that geology thin slice is identified, that rock or mineral sample are ground to flakiness, at the Crystallization Characteristics of polarized light microscopy Microscopic observation mineral, measure its optical property, determine the mineralogical composition of rock, study its structure, structure, the genesis sequence of assaying, determine rock type and genetic feature thereof, carry out Rock Name.Thin slice identification method is the research means often using in geology oil prospecting gas finding work.

S103: described rock specimens is carried out to hole and ooze measurement, must arrive hole and ooze basic parameter, described hole is oozed basic parameter and comprised factor of porosity, permeability and density.The density of herein mentioning comprises dry rock density, water saturation sample rate and rock particles density of matrix, and rock density in general just refers to dry rock density.Density when dry rock density refers to and is air in blowhole, density when water saturation sample rate refers to and is full of water in blowhole, rock particles density of matrix refers to and does not comprise the density of hole at the particulate component of interior composition rock.

Core experiment measurement is to obtain reservoir rock information comparatively accurately by the underground rock core of direct measurement, comprises factor of porosity, permeability, mineralogical composition, density, p-and s-wave velocity etc.These information contribute to understand the relation between reservoir elastic characteristic and physical parameter, the foundation of guiding reservoir rock theoretical model.

It is the one that core experiment is measured that measurement is oozed in hole, and hole is oozed to measure and referred to that sample is put into vacuum oven does dry processing, with electronic balance, measures its quality, and error is in 0.01g.Utilize hole to ooze factor of porosity φ and the permeability κ of translocation system (helium method) measurement sample.Under gaging pressure, the porosity and permeability of sample all can change.Because mineral grain volume change is very little, after rock pressurized, the variation of volume can be approximately equal to the variation of volume of voids, when hole, presses when constant, and factor of porosity can be measured by hole hydraulic fluid with the variation of confined pressure.

Utilize diameter and the length of vernier caliper measurement rock core cylinder, volume calculated V _b, utilizing electronic balance to measure dry sample quality is W _dryso dry rock density is:

${\mathrm{\ρ}}_{\mathrm{dry}}=\frac{W_{\mathrm{dry}}}{V_b}$

Water saturation sample rate is:

ρ _wet=ρ _dry+φρ _w

Wherein, φ is rock porosity, ρ _wfor the density of water.

Rock particles density of matrix is:

${\mathrm{\ρ}}_m=\frac{{\mathrm{\ρ}}_{\mathrm{dry}}}{(1-\mathrm{\φ})}$

Porosity and permeability utilizes hole to ooze measurement equipment and measures by helium method, and helium is filled with in blowhole, and instrument can be measured the amount of being filled with, and calculates factor of porosity; The amount of passing through the gas of rock in unit interval, is permeability.

S104: carry out pore Structure Analysis according to described pore shape and sedimentary facies belt, ooze basic parameter and the dry skeleton pattern of differential EFFECTIVE MEDIUM model construction rock according to described rock basic parameter, hole.

In this step, first can carry out pore Structure Analysis according to described pore shape and sedimentary facies belt.When hole is more flat, aspect ratio <0.1, hole is slit formation hole, when the aspect ratio of hole is larger, is erodible hole.When given rock composition and pore space, differential EFFECTIVE MEDIUM model can be used to estimate the equivalent elastic modulus of rock skeleton, i.e. rock skeleton modeling.

Differential EFFECTIVE MEDIUM (DEM) theory is by adding gradually inclusion to carry out mutually simulated dual phase mixture toward solid mineral in mutually.Suppose that solid mineral is mutually 1, inclusion is mutually 2, and initial state is to only have mutually 1 not mutually 2, progressively adds afterwards mutually 2, until reach the each component content needing.Generally, with material 1, as principal phase the inclusion that adds gradually material 2 to form, and also add gradually compared with the inclusion that material 1 forms as principal phase with material 2, can produce different equivalent attributes.For multiple inclusion shape or multiple inclusion composition, its concrete moduli not only depends on the volume content of final each composition, also depends on the order that inclusion adds.Toward solid mineral, adding gradually the process of inclusion in is mutually a gedanken experiment, and the differentiation of occurring in nature rock porosity is very complicated.

The bulk modulus K of the dry skeleton pattern of rock building ^*with modulus of shearing μ ^*coupled differential group be:

$(1-y)\frac{{\mathrm{dK}}^{*}\left(y\right)}{\mathrm{dy}}=[K_2-K^{*}\left(y\right)]P^{(*2)}\left(y\right)$

$(1-y)\frac{{\mathrm{d\&mu;}}^{*}\left(y\right)}{\mathrm{dy}}=[{\mathrm{\&mu;}}_2-{\mathrm{\&mu;}}^{*}\left(y\right)]Q^{(*2)}\left(y\right)$

Wherein, K ₂for bulk modulus, the μ of hole ₂for the modulus of shearing of hole, y is the content of hole, and P, Q are geometry factor, starting condition K ^*(0)=K ₁, μ ^*(0)=μ ₁, K ₁for the bulk modulus of original mineral composition, μ ₁for the modulus of shearing of original mineral composition.K1 represents initial principal phase, i.e. virgin state; K2 represents the inclusion adding, and generally can think hole.For fluid inclusion and empty inclusion, y equals factor of porosity φ, and P and Q are the geometry factors of some inclusion shapes that table 1 is given, and subscript m and i refer to respectively background material and inclusion material.

Table 1

Wherein, $\mathrm{\&beta;}=\mathrm{\&mu;}\frac{3K+\mathrm{\&mu;}}{3K+4\mathrm{\&mu;}},\mathrm{\&gamma;}=\mathrm{\&mu;}\frac{3K+\mathrm{\&mu;}}{3K+7\mathrm{\&mu;}},\mathrm{\&zeta;}=\frac{\mathrm{\&mu;}}{6}\frac{9K+8\mathrm{\&mu;}}{K+2\mathrm{\&mu;}},$ α is hole aspect ratio.

The process of rock skeleton modeling of the present invention as mentioned above.Survey target reservoir rock information, comprises the basic parameters such as lithology, mineralogical composition, shale index, depth of burial, porosity type, Diagn, temperature and pressure.Utilize the technological means such as the evaluation of geology thin slice, log data and measured data of experiment (ultrasonic measurement, nanometer CT scan etc.) to obtain parameter of pore structure (face rate, hole aspect ratio, scale factor, percent continuity etc.).According to different pore textures, utilize differential EFFECTIVE MEDIUM model to set up respectively corresponding rock skeleton model.

In above technical scheme, it is important step of the present invention that the different pore structures of growing according to different sedimentary facies belts is set up respectively corresponding rock skeleton model.Wherein, geology thin slice identifies that measuring with core experiment the division that is pore texture from geology angle and experimental viewpoint respectively provides theoretical foundation and data reference.By the Microscopic observation of petrographic thin section, can determine micropore structure feature and the corresponding sedimentary facies belt of rock, by the ultrasonic measurement of core sample, can obtain the rock skeleton elastic parameter of reservoir, for the prediction of gas reservoir quantification provides important support.

S105: the dry skeleton pattern of described rock is carried out to fluid substitution, generate rock physics plate.In concrete embodiment, this step can realize by following step: the dry skeleton pattern of rock based on described, and utilize Biot-Rayleigh system of equations to carry out fluid substitution, generate the rock physics plate based on different pore structures.

2004, Pride, Berryman etc. have proposed double-porosity system theory (abbreviation double porosity media) and have analyzed elastic wave propagation and the attenuation law in unsaturated media, containing pore and containing water hole in the corresponding unsaturated rock of " diplopore " difference in this case.For a kind of form wave propagation equations succinct, that parameter is few, each parameter possesses physical realizability of further deriving meets practical application and commercial production needs, Ba Jing etc. are based on Biot theoretical frame, derive Biot-Rayleigh equation (being called for short B-R equation) of describing unsaturated rock seismic wave propagation rule, and be successfully applied to the engineering problem of actual gas reservoir exploration.

Ba Jing etc. adopt the local fluid of bubble in the lower unsaturated rock of Rayleigh theoretical description compressional wave excitation to flow, and have derived double-porosity system wave propagation equations, i.e. Biot-Rayleigh equation from the Hamilton principle of classical mechanics.This equation can be simulated the situation of a class fluid, two kinds of skeletons; Also the situation that can simulate a class skeleton, two class fluids, inclusion is in full accord with the solid skeletal of background phase, and main difference is gentle to the difference aspect density, elastic modulus and glutinousness from the water of pore space inside between the two.

Biot-Rayleigh equation is as follows:

Wherein, u=[u ₁, u ₂, u ₃], $U^{\left(1\right)}=[U_1^{\left(1\right)},U_2^{\left(1\right)},U_3^{\left(1\right)}],U^{\left(2\right)}=[U_1^{\left(2\right)},U_2^{\left(2\right)},U_3^{\left(2\right)}]$ Represent respectively the space vector displacement of three kinds of components, subscript 1,2,3 represents three directions of vector space,

represent the local fluid deformation increment producing in the seismic event process of motivation.

$e_{\mathrm{ij}}=\frac{1}{2}(\frac{{\&PartialD;u}_i}{\&PartialD;x_j}+\frac{{\&PartialD;u}_j}{{\&PartialD;x}_i}),{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(1\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(1\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(1\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(2\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(2\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(2\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},$

X ₁, x ₂with x ₃represent respectively the coordinate of three directions.φ ₁and φ ₂represent the absolute porosity of two class holes, the total porosity φ=φ of rock ₁+ φ ₂; φ ₁₀with φ ₂₀represent respectively the local factor of porosity in two regions, as rock interior only contains a kind of skeleton, saturated have two kinds of fluids, φ ₁₀=φ ₂₀=φ.ρ _f1and η ₁represent density and the viscosity of background phase fluid.R ₀represent bubble radius, κ ₁₀represent rock permeability.

A, N, Q ₁, R ₁, Q ₂, R ₂represent six Biot elastic parameters in double porosity media, can carry out explicit calculating and estimation by the petrophysical parameter on the bases such as the elastic modulus of the bulk modulus of the elastic modulus of rock skeleton, fluid, factor of porosity, solid matrix; ρ ₁₁, ρ ₁₂, ρ ₁₃, ρ ₂₂with ρ ₃₃represent five density parameters in double porosity media, at the single rock particles to rock interior, adopt under the prerequisite of spherical approximate hypothesis, these five density parameters also can carry out explicit calculating and estimation according to the component ratio of the density of the density of solid particle in rock, pore fluid, factor of porosity and different pore structures.The calculating of parameters and estimating and measuring method are known technology, and if the patent No. is the scheme of mentioning in 201310308550.5,201210335739.9 patent of invention, the present invention repeats no more.The solution procedure of Biot-Rayleigh equation is also documented in above-mentioned two patents, therefore repeats no more herein.In above formula, ξ is the displacement of fluid increment under seismic event extruding, and b represents Biot Dissipation Parameters,

wherein η, φ and κ represent respectively fluid viscosity, factor of porosity and permeability.For the pore media containing two-phase fluid, b ₁, b ₂represent respectively containing water hole, containing the Biot dissipation factor in pore, (the corresponding two class holes of subscript 1,2).

Such as adopting plane-wave analy-sis to solve after Biot-Rayleigh equation, can obtain velocity of longitudinal wave, shear wave velocity and density, based on these three parameters, can make various rock physics plates.The rock physics plate that this step generates based on Biot-Rayleigh equation has comprised the rock physics plate generating according to all kinds of sensitive parameters.All kinds of sensitive parameters of herein mentioning comprise: velocity of longitudinal wave, shear wave velocity, density, p-and s-wave velocity ratio, Poisson ratio, elastic parameter, Young modulus etc.

S106: the pre-stack seismic inversion data of obtaining carbonate reservoir;

S107: described pre-stack seismic inversion data and described rock physics plate are carried out to intersection, obtain the factor of porosity of described carbonate reservoir and predicting the outcome of gas saturation.Fig. 4 is the particular flow sheet of step S107, and as shown in Figure 4, this step specifically comprises:

S401: obtain p-wave impedance from described pre-stack seismic inversion data;

S402: using described p-wave impedance as transverse axis;

S403: obtain p-and s-wave velocity ratio from described pre-stack seismic inversion data;

S404: described p-and s-wave velocity is compared to the longitudinal axis;

S405: described rock physics plate is mapped in the coordinate system being comprised of described transverse axis, the longitudinal axis;

S406: adjust the coordinate of described rock physics plate, obtain the factor of porosity of target reservoir section and the predicting the outcome of gas saturation of described carbonate reservoir.

In concrete embodiment, rock physics plate and the loose point of pre-stack seismic inversion data are carried out to intersection, wherein, seismic inversion data are mainly p-wave impedance and p-and s-wave velocity compares data, p-wave impedance (X-axis)-p-and s-wave velocity than (Y-axis) coordinate system under, the grid ordinate representative prediction factor of porosity (becoming from right to left large) of rock physics plate, horizontal line represents gas saturation (becoming from top to bottom large), observe the matching degree of loose some mapping position and plate, adjust rock physics plate, and inverting target reservoir factor of porosity and gas saturation.

The process flow diagram of the embodiment two of the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic that Fig. 2 provides for the embodiment of the present invention, as shown in Figure 2, step S101 in Fig. 1 is identical to step S204 with step S201 in Fig. 2 to step S104, step S105 in Fig. 1 is identical to step S211 with step S209 in Fig. 2 to step S107, repeat no more, the method also comprises in embodiment two herein:

S205: the geologic report that obtains carbonate reservoir;

S206: the log data of obtaining carbonate reservoir;

S207: the logging data that obtains carbonate reservoir;

S208: the dry skeleton pattern of described rock is proofreaied and correct according to described geologic report, log data and logging data.Geologic report, log data and logging data can provide underground stratum age, reservoir information (the such as concrete station interval of lithology, mineralogical composition, gas-bearing formation and water layer etc.), it is generally acknowledged that these data are reliable.In the dry skeleton modeling process of rock, need to make model more rationally, more meet underground truth with reference to these data.Geologic report has provided the large-scale geological condition general introduction in work area, and log data has recorded well week lithology and the mineralogical composition of interior each formation rock among a small circle, in dry skeleton modeling, must input parameter be set according to these information.It is limestone that for example the present invention applies work area carbonate reservoir rock lithology, and its essential mineral composition is kalzit, attached containing a small amount of shale, so just with kalzit and shale, carries out dry skeleton modeling.Well-log information has recorded the information such as the speed, density, factor of porosity of formation rock, and these are all the references that input parameter must be inputted and proofread and correct to dry skeleton modeling.These data have reflected the information of subsurface rock intuitively, if there is no these information, just can not accurately set up dry skeleton pattern.

The process flow diagram of the embodiment three of the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic that Fig. 3 provides for the embodiment of the present invention, as shown in Figure 3, step S101 in Fig. 1 is identical to step S305 with step S301 in Fig. 3 to step S105, step S106 in Fig. 1 is identical to step S310 with step S309 in Fig. 3 to step S107, repeat no more, the method also comprises in embodiment three herein:

S306: described rock specimens is carried out to ultrasonic measurement, obtain measurement result, described measurement result comprises dry velocity of longitudinal wave, dry shear wave velocity, moisture velocity of longitudinal wave and moisture shear wave velocity.

Single fluid saturation experiments, is to make the saturated single fluid of rock specimens, measures rock p-and s-wave velocity under this state variation relation with pressure, temperature.

Ultrasonic measurement experimental facilities top pressure 20000psi, 150-200 degrees Celsius of maximum temperatures, are applicable to measuring multiple rock p-and s-wave velocity, anisotropy, the resistivity etc. such as sandstone, mud stone, carbonatite, oil-sand.Ultrasonic measurement system is by installation compositions such as digital oscilloscope, impulse ejection receiver, high temperature and high pressure containers, measuring sonde, digital mercury, temperature controllers.Figure 17 is conventional ultrasound measuring system schematic diagram, and as shown in Figure 17, except high temperature and high pressure containers, all the other equipment can be divided into four subsystems: signal acquiring system, hole pressing system, confined pressure system and heating and cooling system.Utilize the gum cover clearance hole of parcel core sample to press and confined pressure, the pore pressure and the reservoir pressure that can simulate formation condition rock be subject to.Heating and cooling system, for the temperature of Quality control, makes it reach formation temperature.

Adopt pulse through-transmission technique to carry out supersonic velocity measurement.The electric signal of impulse sender transmitting is converted into ultrasound wave through compressional wave transducer or shear wave transducer, and ultrasound wave penetrates rock core and received by another transducer, is finally sent to oscillograph and carries out signals collecting.Pick up compressional wave and the first arrival of shear wave signal, by whilst on tour, proofread and correct with conversion and can obtain p-and s-wave velocity.First arrival picking errors will be controlled in 0.03 μ s.

S307: the measurement result based on described is determined preferred sensitive parameter.Experiment measuring the rock parameter under dry and water saturation two states, the measurement result obtaining comprises dry velocity of longitudinal wave, dry shear wave velocity, moisture velocity of longitudinal wave and moisture shear wave velocity.These parameters are crossed mutually, if the data point under two states is distinguished obviously, illustrate that the parameter crossing is preferred sensitive parameter.As: the difference of supposing the dry velocity of longitudinal wave that measures and moisture velocity of longitudinal wave is larger, and velocity of longitudinal wave can be directly as preferred sensitive parameter, if difference is little, velocity of longitudinal wave not can be used as sensitive parameter; If the p-and s-wave velocity calculating based on measurement result differs greatly in dry and moisture situation than (or other certain elastic parameters), p-and s-wave velocity can be used as preferred sensitive parameter than (or other certain elastic parameters).

S308: pick out preferred rock physics plate according to described preferred sensitive parameter from described rock physics plate.The preferred sensitive parameter that experiment measuring obtains, can provide reference for the parameter of rock physics modeling, improves modeling accuracy.

In other embodiments of the present invention, utilize the given rock skeleton information of EFFECTIVE MEDIUM THEORY, according to known a kind of saturated with fluid or drying regime, Equivalent Elasticity parameter while calculating saturated other fluid of rock, preferably sensibility elasticity parameter.Utilize Biot-Rayleigh equation computing rock physics plate.

The process flow diagram of the embodiment four of the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic that Fig. 5 provides for the embodiment of the present invention, as shown in Figure 5, step S101 in Fig. 1 is identical to step S507 with step S501 in Fig. 5 to step S107, repeat no more, the method also comprises in embodiment four herein:

S508: the raw log data that obtains carbonate reservoir;

S509: determine well logging interpretation achievement according to described raw log data;

S510: predicting the outcome of described factor of porosity and gas saturation verified according to described well logging interpretation achievement.Gas-bearing formation position in gas-bearing formation position and well logging interpretation achievement that contrast predicts the outcome, if basically identical, illustrates that prediction accurately rationally.

Be as mentioned above the gas reservoir Forecasting Methodology of a kind of carbonate reservoir based on pore structure characteristic provided by the invention, by geologic report, log data, logging data, geology thin slice, identify and core experiment measurement result, obtain and comprise factor of porosity, permeability, mineral content, pore structure characteristic isolith stone basic parameter, generate the rock dry skeleton pattern corresponding with reservoir different pore structures; Based on the dry skeleton pattern of rock, utilize Biot-Rayleigh system of equations to carry out fluid substitution, generate the rock physics plate based on different pore structures; By the pre-stack seismic inversion data of different pore structures development belt and corresponding rock physics template intersection, utilize factor of porosity and the gas saturation of reflection method inverting target reservoir from rock physics template.

The gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that the present invention also proposes, Fig. 6 is the structured flowchart of the embodiment one of gas reservoir prognoses system, as shown in Figure 6, described system comprises:

Rock specimens harvester 100, for gathering the rock specimens of carbonate reservoir target reservoir section.In concrete embodiment, can adopt conventional method of seismic prospecting to gather the rock specimens of carbonate reservoir target reservoir section.

Geology thin slice identification apparatus 200, carries out the evaluation of geology thin slice for the rock specimens to described, obtains rock basic parameter, and described rock basic parameter comprises rock composition, pore shape, face rate and sedimentary facies belt.It is the method for identifying rocks and minerals under polarizing microscope that geology thin slice is identified, that rock or mineral sample are ground to flakiness, at the Crystallization Characteristics of polarized light microscopy Microscopic observation mineral, measure its optical property, determine the mineralogical composition of rock, study its structure, structure, the genesis sequence of assaying, determine rock type and genetic feature thereof, carry out Rock Name.Thin slice identification method is the research means often using in geology oil prospecting gas finding work.

Measurement mechanism 300 is oozed in hole, carries out hole ooze measurement for the rock specimens to described, must arrive hole and ooze basic parameter, and described hole is oozed basic parameter and comprised factor of porosity, permeability and density.The density of herein mentioning comprises dry rock density, water saturation sample rate and rock particles density of matrix, and rock density in general just refers to dry rock density.Density when dry rock density refers to and is air in blowhole, density when water saturation sample rate refers to and is full of water in blowhole, rock particles density of matrix refers to and does not comprise the density of hole at the particulate component of interior composition rock.

Core experiment measurement is to obtain reservoir rock information comparatively accurately by the underground rock core of direct measurement, comprises factor of porosity, permeability, mineralogical composition, density, p-and s-wave velocity etc.These information contribute to understand the relation between reservoir elastic characteristic and physical parameter, the foundation of guiding reservoir rock theoretical model.

It is the one that core experiment is measured that measurement is oozed in hole, and hole is oozed to measure and referred to that sample is put into vacuum oven does dry processing, with electronic balance, measures its quality, and error is in 0.01g.Utilize hole to ooze factor of porosity φ and the permeability κ of translocation system (helium method) measurement sample.Under gaging pressure, the porosity and permeability of sample all can change.Because mineral grain volume change is very little, after rock pressurized, the variation of volume can be approximately equal to the variation of volume of voids, when hole, presses when constant, and factor of porosity can be measured by hole hydraulic fluid with the variation of confined pressure.

Utilize diameter and the length of vernier caliper measurement rock core cylinder, volume calculated V _b, utilizing electronic balance to measure dry sample quality is W _dryso dry rock density is:

${\mathrm{\&rho;}}_{\mathrm{dry}}=\frac{W_{\mathrm{dry}}}{V_b}$

Water saturation sample rate is:

ρ _wet=ρ _dry+φρ _w

Wherein, φ is rock porosity, ρ _wfor the density of water.

Rock particles density of matrix is:

${\mathrm{\&rho;}}_m=\frac{{\mathrm{\&rho;}}_{\mathrm{dry}}}{(1-\mathrm{\&phi;})}$

Porosity and permeability utilizes hole to ooze measurement equipment and measures by helium method, and helium is filled with in blowhole, and instrument can be measured the amount of being filled with, and calculates factor of porosity; The amount of passing through the gas of rock in unit interval, is permeability.

The dry skeleton member device 400 of rock, for carrying out pore Structure Analysis according to described pore shape and sedimentary facies belt, oozes basic parameter and the dry skeleton pattern of differential EFFECTIVE MEDIUM model construction rock according to described rock basic parameter, hole.In this step, first can carry out pore Structure Analysis according to described pore shape and sedimentary facies belt.When hole is more flat, aspect ratio <0.1, hole is slit formation hole, when the aspect ratio of hole is larger, is erodible hole.When given rock composition and pore space, differential EFFECTIVE MEDIUM model can be used to estimate the equivalent elastic modulus of rock skeleton, i.e. rock skeleton modeling.

Differential EFFECTIVE MEDIUM (DEM) theory is by adding gradually inclusion to carry out mutually simulated dual phase mixture toward solid mineral in mutually.Suppose that solid mineral is mutually 1, inclusion is mutually 2, and initial state is to only have mutually 1 not mutually 2, progressively adds afterwards mutually 2, until reach the each component content needing.Generally, with material 1, as principal phase the inclusion that adds gradually material 2 to form, and also add gradually compared with the inclusion that material 1 forms as principal phase with material 2, can produce different equivalent attributes.For multiple inclusion shape or multiple inclusion composition, its concrete moduli not only depends on the volume content of final each composition, also depends on the order that inclusion adds.Toward solid mineral, adding gradually the process of inclusion in is mutually a gedanken experiment, and the differentiation of occurring in nature rock porosity is very complicated.

The bulk modulus K of the dry skeleton pattern of rock building ^*with modulus of shearing μ ^*coupled differential group be:

$(1-y)\frac{{\mathrm{dK}}^{*}\left(y\right)}{\mathrm{dy}}=[K_2-K^{*}\left(y\right)]P^{(*2)}\left(y\right)$

$(1-y)\frac{{\mathrm{d\&mu;}}^{*}\left(y\right)}{\mathrm{dy}}=[{\mathrm{\&mu;}}_2-{\mathrm{\&mu;}}^{*}\left(y\right)]Q^{(*2)}\left(y\right)$

Wherein, K ₂for bulk modulus, the μ of hole ₂for the modulus of shearing of hole, y is the content of hole, and P, Q are geometry factor, starting condition K ^*(0)=K ₁, μ ^*(0)=μ ₁, K ₁for the bulk modulus of original mineral composition, μ ₁for the modulus of shearing of original mineral composition.K1 represents initial principal phase, i.e. virgin state; K2 represents the inclusion adding, and generally can think hole.For fluid inclusion and empty inclusion, y equals factor of porosity φ, and P and Q are the geometry factors of some inclusion shapes that table 1 is given, and subscript m and i refer to respectively background material and inclusion material.

The process of rock skeleton modeling of the present invention as mentioned above.Survey target reservoir rock information, comprises the basic parameters such as lithology, mineralogical composition, shale index, depth of burial, porosity type, Diagn, temperature and pressure.Utilize the technological means such as the evaluation of geology thin slice, log data and measured data of experiment (ultrasonic measurement, nanometer CT scan etc.) to obtain parameter of pore structure (face rate, hole aspect ratio, scale factor, percent continuity etc.).According to different pore textures, utilize differential EFFECTIVE MEDIUM model to set up respectively corresponding rock skeleton model.

In above technical scheme, it is important step of the present invention that the different pore structures of growing according to different sedimentary facies belts is set up respectively corresponding rock skeleton model.Wherein, geology thin slice identifies that measuring with core experiment the division that is pore texture from geology angle and experimental viewpoint respectively provides theoretical foundation and data reference.By the Microscopic observation of petrographic thin section, can determine micropore structure feature and the corresponding sedimentary facies belt of rock, by the ultrasonic measurement of core sample, can obtain the rock skeleton elastic parameter of reservoir, for the prediction of gas reservoir quantification provides important support.

Rock physics plate generating apparatus 500, carries out fluid substitution for the dry skeleton pattern of the rock to described, generates rock physics plate.In concrete embodiment, this step can realize by following step: the dry skeleton pattern of rock based on described, and utilize Biot-Rayleigh system of equations to carry out fluid substitution, generate the rock physics plate based on different pore structures.

2004, Pride, Berryman etc. have proposed double-porosity system theory (abbreviation double porosity media) and have analyzed elastic wave propagation and the attenuation law in unsaturated media, containing pore and containing water hole in the corresponding unsaturated rock of " diplopore " difference in this case.For a kind of form wave propagation equations succinct, that parameter is few, each parameter possesses physical realizability of further deriving meets practical application and commercial production needs, Ba Jing etc. are based on Biot theoretical frame, derive Biot-Rayleigh equation (being called for short B-R equation) of describing unsaturated rock seismic wave propagation rule, and be successfully applied to the engineering problem of actual gas reservoir exploration.

Ba Jing etc. adopt the local fluid of bubble in the lower unsaturated rock of Rayleigh theoretical description compressional wave excitation to flow, and have derived double-porosity system wave propagation equations, i.e. Biot-Rayleigh equation from the Hamilton principle of classical mechanics.This equation can be simulated the situation of a class fluid, two kinds of skeletons; Also the situation that can simulate a class skeleton, two class fluids, inclusion is in full accord with the solid skeletal of background phase, and main difference is gentle to the difference aspect density, elastic modulus and glutinousness from the water of pore space inside between the two.

Biot-Rayleigh equation is as follows:

Wherein, u=[u ₁, u ₂, u ₃], $U^{\left(1\right)}=[U_1^{\left(1\right)},U_2^{\left(1\right)},U_3^{\left(1\right)}],U^{\left(2\right)}=[U_1^{\left(2\right)},U_2^{\left(2\right)},U_3^{\left(2\right)}]$ Represent respectively the space vector displacement of three kinds of components, subscript 1,2,3 represents three directions of vector space,

represent the local fluid deformation increment producing in the seismic event process of motivation.

$e_{\mathrm{ij}}=\frac{1}{2}(\frac{{\&PartialD;u}_i}{\&PartialD;x_j}+\frac{{\&PartialD;u}_j}{{\&PartialD;x}_i}),{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(1\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(1\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(1\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(2\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(2\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(2\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},$

X ₁, x ₂with x ₃represent respectively the coordinate of three directions.φ ₁and φ ₂represent the absolute porosity of two class holes, the total porosity φ=φ of rock ₁+ φ ₂; φ ₁₀with φ ₂₀represent respectively the local factor of porosity in two regions, as rock interior only contains a kind of skeleton, saturated have two kinds of fluids, φ ₁₀=φ ₂₀=φ.ρ _f1and η ₁represent density and the viscosity of background phase fluid.R ₀represent bubble radius, κ ₁₀represent rock permeability.

A, N, Q ₁, R ₁, Q ₂, R ₂represent six Biot elastic parameters in double porosity media, can carry out explicit calculating and estimation by the petrophysical parameter on the bases such as the elastic modulus of the bulk modulus of the elastic modulus of rock skeleton, fluid, factor of porosity, solid matrix; ρ ₁₁, ρ ₁₂, ρ ₁₃, ρ ₂₂with ρ ₃₃represent five density parameters in double porosity media, at the single rock particles to rock interior, adopt under the prerequisite of spherical approximate hypothesis, these five density parameters also can carry out explicit calculating and estimation according to the component ratio of the density of the density of solid particle in rock, pore fluid, factor of porosity and different pore structures.The calculating of parameters and estimating and measuring method are known technology, and if the patent No. is the scheme of mentioning in 201310308550.5,201210335739.9 patent of invention, the present invention repeats no more.The solution procedure of Biot-Rayleigh equation is also documented in above-mentioned two patents, therefore repeats no more herein.In above formula, ξ is the displacement of fluid increment under seismic event extruding, and b represents Biot Dissipation Parameters,

wherein η, φ and κ represent respectively fluid viscosity, factor of porosity and permeability.For the pore media containing two-phase fluid, b ₁, b ₂represent respectively containing water hole, containing the Biot dissipation factor in pore,

(the corresponding two class holes of subscript 1,2).

Such as adopting plane-wave analy-sis to solve after Biot-Rayleigh equation, can obtain velocity of longitudinal wave, shear wave velocity and density, based on these three parameters, can make various rock physics plates.The rock physics plate that this step generates based on Biot-Rayleigh equation has comprised the rock physics plate generating according to all kinds of sensitive parameters.All kinds of sensitive parameters of herein mentioning comprise: velocity of longitudinal wave, shear wave velocity, density, p-and s-wave velocity ratio, Poisson ratio, elastic parameter, Young modulus etc.

Pre-stack seismic inversion data acquisition facility 600, for obtaining the pre-stack seismic inversion data of carbonate reservoir;

Gas saturation prediction unit 700, for described pre-stack seismic inversion data and described rock physics plate are carried out to intersection, obtains the factor of porosity of described carbonate reservoir and predicting the outcome of gas saturation.Fig. 9 is the concrete structure block diagram of gas saturation prediction unit 700, and as shown in Figure 9, gas saturation prediction unit specifically comprises:

Total wave impedance acquisition module 701, obtains p-wave impedance for the pre-stack seismic inversion data from described;

Transverse axis arranges module 702, for using described p-wave impedance as transverse axis;

P-and s-wave velocity, than acquisition module 703, obtains p-and s-wave velocity ratio for the pre-stack seismic inversion data from described;

The longitudinal axis arranges module 704, for described p-and s-wave velocity is compared to the longitudinal axis;

Mapping block 705, for being mapped to by described rock physics plate the coordinate system being comprised of described transverse axis, the longitudinal axis;

Gas saturation prediction module 706, for adjusting the coordinate of described rock physics plate, obtains the factor of porosity of target reservoir section and the predicting the outcome of gas saturation of described carbonate reservoir.

In concrete embodiment, rock physics plate and the loose point of pre-stack seismic inversion data are carried out to intersection, wherein, seismic inversion data are mainly p-wave impedance and p-and s-wave velocity compares data, p-wave impedance (X-axis)-p-and s-wave velocity than (Y-axis) coordinate system under, the grid ordinate representative prediction factor of porosity (becoming from right to left large) of rock physics plate, horizontal line represents gas saturation (becoming from top to bottom large), observe the matching degree of loose some mapping position and plate, adjust rock physics plate, and inverting target reservoir factor of porosity and gas saturation.

The structured flowchart of the embodiment two of the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Fig. 7 provides for the embodiment of the present invention, as shown in Figure 7, this system also comprises in embodiment two:

Geologic report acquisition device 800, for obtaining the geologic report of carbonate reservoir;

Log data acquisition device 900, for obtaining the log data of carbonate reservoir;

Logging data acquisition device 1100, for obtaining the logging data of carbonate reservoir;

The dry skeleton pattern means for correcting 1200 of rock, for proofreading and correct the dry skeleton pattern of described rock according to described geologic report, log data and logging data.Geologic report, log data and logging data can provide underground stratum age, reservoir information (the such as concrete station interval of lithology, mineralogical composition, gas-bearing formation and water layer etc.), it is generally acknowledged that these data are reliable.In the dry skeleton modeling process of rock, need to make model more rationally, more meet underground truth with reference to these data.

Geologic report has provided the large-scale geological condition general introduction in work area, and log data has recorded well week lithology and the mineralogical composition of interior each formation rock among a small circle, in dry skeleton modeling, must input parameter be set according to these information.It is limestone that for example the present invention applies work area carbonate reservoir rock lithology, and its essential mineral composition is kalzit, attached containing a small amount of shale, so just with kalzit and shale, carries out dry skeleton modeling.Well-log information has recorded the information such as the speed, density, factor of porosity of formation rock, and these are all the references that input parameter must be inputted and proofread and correct to dry skeleton modeling.These data have reflected the information of subsurface rock intuitively, if there is no these information, just can not accurately set up dry skeleton pattern.

The structured flowchart of the embodiment three of the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Fig. 8 provides for the embodiment of the present invention, as shown in Figure 8, this system also comprises in embodiment three:

Ultrasonic measuring device 1300, carries out ultrasonic measurement for the rock specimens to described, obtains measurement result, and described measurement result comprises dry velocity of longitudinal wave, dry shear wave velocity, moisture velocity of longitudinal wave and moisture shear wave velocity.Single fluid saturation experiments, is to make the saturated single fluid of rock specimens, measures rock p-and s-wave velocity under this state variation relation with pressure, temperature.

Ultrasonic measurement experimental facilities top pressure 20000psi, 150-200 degrees Celsius of maximum temperatures, are applicable to measuring multiple rock p-and s-wave velocity, anisotropy, the resistivity etc. such as sandstone, mud stone, carbonatite, oil-sand.Ultrasonic measurement system is by installation compositions such as digital oscilloscope, impulse ejection receiver, high temperature and high pressure containers, measuring sonde, digital mercury, temperature controllers.Figure 17 is conventional ultrasound measuring system schematic diagram, and as shown in Figure 17, except high temperature and high pressure containers, all the other equipment can be divided into four subsystems: signal acquiring system, hole pressing system, confined pressure system and heating and cooling system.Utilize the gum cover clearance hole of parcel core sample to press and confined pressure, the pore pressure and the reservoir pressure that can simulate formation condition rock be subject to.Heating and cooling system, for the temperature of Quality control, makes it reach formation temperature.

Adopt pulse through-transmission technique to carry out supersonic velocity measurement.The electric signal of impulse sender transmitting is converted into ultrasound wave through compressional wave transducer or shear wave transducer, and ultrasound wave penetrates rock core and received by another transducer, is finally sent to oscillograph and carries out signals collecting.Pick up compressional wave and the first arrival of shear wave signal, by whilst on tour, proofread and correct with conversion and can obtain p-and s-wave velocity.First arrival picking errors will be controlled in 0.03 μ s.

Preferably sensitive parameter device for sorting 1400, determines preferred sensitive parameter for the measurement result based on described.Experiment measuring the rock parameter under dry and water saturation two states, the measurement result obtaining comprises dry velocity of longitudinal wave, dry shear wave velocity, moisture velocity of longitudinal wave and moisture shear wave velocity.These parameters are crossed mutually, if the data point under two states is distinguished obviously, illustrate that the parameter crossing is preferred sensitive parameter.As: the difference of supposing the dry velocity of longitudinal wave that measures and moisture velocity of longitudinal wave is larger, and velocity of longitudinal wave can be directly as preferred sensitive parameter, if difference is little, velocity of longitudinal wave not can be used as sensitive parameter; If the p-and s-wave velocity calculating based on measurement result differs greatly in dry and moisture situation than (or other certain elastic parameters), p-and s-wave velocity can be used as preferred sensitive parameter than (or other certain elastic parameters).

Rock physics plate device for sorting 1500, for picking out preferred rock physics plate according to described preferred sensitive parameter from described rock physics plate.The preferred sensitive parameter that experiment measuring obtains, can provide reference for the parameter of rock physics modeling, improves modeling accuracy.

In other embodiments of the present invention, utilize the given rock skeleton information of EFFECTIVE MEDIUM THEORY, according to known a kind of saturated with fluid or drying regime, Equivalent Elasticity parameter while calculating saturated other fluid of rock, preferably sensibility elasticity parameter.Utilize Biot-Rayleigh equation computing rock physics plate.

The structured flowchart of the embodiment four of the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic that Figure 10 provides for the embodiment of the present invention, as shown in Figure 10, this system also comprises in embodiment four:

Log data acquisition device 1600, for obtaining the raw log data of carbonate reservoir;

Well logging interpretation achievement determining device 1700, for determining well logging interpretation achievement according to described raw log data;

The demo plant 1800 that predicts the outcome, for verifying predicting the outcome of described factor of porosity and gas saturation according to described well logging interpretation achievement.Gas-bearing formation position in gas-bearing formation position and well logging interpretation achievement that contrast predicts the outcome, if basically identical, illustrates that prediction accurately rationally.

Be as mentioned above the gas reservoir prognoses system of a kind of carbonate reservoir based on pore structure characteristic provided by the invention, by geologic report, log data, logging data, geology thin slice, identify and core experiment measurement result, obtain and comprise factor of porosity, permeability, mineral content, pore structure characteristic isolith stone basic parameter, generate the rock dry skeleton pattern corresponding with reservoir different pore structures; Based on the dry skeleton pattern of rock, utilize Biot-Rayleigh system of equations to carry out fluid substitution, generate the rock physics plate based on different pore structures; By the pre-stack seismic inversion data of different pore structures development belt and corresponding rock physics template intersection, utilize factor of porosity and the gas saturation of reflection method inverting target reservoir from rock physics template.

Below in conjunction with specific embodiment, introduce in detail technical scheme of the present invention.Take the wheat victory of Amu Darya basin, allow formation of Jurassic carbonate gas reservoirs as goal in research.

(1) geology thin slice is identified

Figure 11 is qualification result under Met22 well reservoir rock thin slice mirror, as shown in Figure 11: and spar calcarenite, take medium sand as main, particle is thicker, and corrosion hole is grown better, and factor of porosity is higher, reservoir space is beneficial to the gathering of oil gas, comprehensively judges that its sedimentary facies belt is positioned at open platform facies;

Figure 12 is qualification result under Met21 well reservoir rock thin slice mirror, as shown in Figure 12: mud spar calcarenite, take fine sand as main, particle is thinner, and pores'growth is poor, kalzit filling most hole and crack, grow build joint, factor of porosity is lower, and reservoir space is unfavorable for the gathering of oil gas, comprehensively judges that its sedimentary facies belt is positioned at restrcted platform facies.

In sum, two mouthfuls of well reservoir rocks are grown and are adhered to different sedimentary facies belts separately, and open platform facies is grown corrosion hole, and restrcted platform facies is grown build joint, and pore texture difference is obvious.

(2) core experiment is measured

The rock specimens schematic diagram of the carbonate reservoir target reservoir section that Figure 13 gathers, as shown in Figure 13, experiment measuring core sample is 15, wherein 13, Met22 well, 2, Met21 well.Core sample all drills through perpendicular to stratum direction, through being processed into the right cylinder of length 50mm, diameter 38mm.At the bottom of top with sand paper polishing rock core cylinder, make it level and smooth and parallel, length variations is less than 0.1mm.The essential mineral composition of sample comprises kalzit, a small amount of rauhkalk, grain thickness inequality.

Figure 14 is core sample nanometer CT scan result, and wherein black represents hole, and grey represents limestone matrix, and white represents stuff kalzit.

Figure 15 is factor of porosity and the density relationship figure of core sample, and the factor of porosity of two samples of Met21 well is all less than 2%, and density is all greater than 2.6g/cm ³, dense, and the sample factor of porosity of Met22 well is all greater than 2%, sample rate all reduces along with the increase of factor of porosity, and has good linear relationship.

Figure 16 is factor of porosity and the permeability graph of a relation of core sample, and two sample permeabilities of Met21 well are all poor, and Met22 well only has two sample permeabilities poor, and all the other sample factor of porosity are higher, and permeability is also better, and factor of porosity and permeability have good correlativity.

In 20 ℃ of temperature, hole, press 22MPa, under the condition of confined pressure 52MPa, core sample is carried out to ultrasonic measurement, Figure 17 is multifunction ultrasonic measuring system.

Figure 18 is the p-and s-wave velocity of rock under drying regime and the graph of a relation of factor of porosity, and p-and s-wave velocity all reduces along with the increase of factor of porosity, and velocity of longitudinal wave changes to 5.145km/s from 6.199km/s, and shear wave velocity changes to 2.872km/s from 3.266km/s.

Figure 19 is the p-and s-wave velocity of rock under water saturation state and the graph of a relation of factor of porosity, and p-and s-wave velocity all reduces along with the increase of factor of porosity, and velocity of longitudinal wave changes to 5.458km/s from 6.323km/s, and shear wave velocity changes to 2.833km/s from 3.264km/s.

Figure 20 is that core sample factor of porosity compares graph of a relation with p-and s-wave velocity.

Figure 21 is that core sample p-wave impedance compares graph of a relation with p-and s-wave velocity.The Vp/Vs of drying regime core sample is substantially between 1.8-1.9, the Vp/Vs of water saturation state core sample is substantially between 1.9-2.0, than the obvious increase of drying regime, and the size (from low-porosity to high porosity) of factor of porosity on the Changing Pattern of Vp/Vs without obvious impact, illustrate that Vp/Vs can effectively distinguish the saturated with fluid state in rock, can be used as the sensitive parameter of fluid detection.

Figure 22 is the affect graph of a relation of reservoir core sample well gap structure on velocity of longitudinal wave, and along with the increase of factor of porosity, dissolution pore and crack all can have a huge impact seimic wave velocity, but dissolution pore is more slow on the impact of speed, and crack is more responsive on the impact of speed.

(3) rock physics modeling and the prediction of gas reservoir quantification

The petrophysical parameter that rock physics modeling adopts is: kalzit bulk modulus 76.8GPa, modulus of shearing 32GPa, water volume modulus 2.51GPa, gas bulk modulus 1.44 × 10 ⁵pa, water viscosity 0.001Pa*s, gas viscosity 0.000022Pa*s, limestone matrix average density 2.7g/cm ³, water-mass density 1.04g/cm ³, air tightness 0.01g/cm ³, average bubble size 2mm.Dissolution pore aspect ratio 0.62, crack aspect ratio 0.02.

Figure 23 is rock physics plate and the M22 well lie geological data X plot based on dissolution pore pore texture, and wherein the loose point of square represents gas-bearing formation, and the loose point of rhombus represents water layer, and the loose point of triangle represents non-reservoir.The loose point of square drops between plate prediction factor of porosity 6%-14% with the loose point of rhombus, and the loose point of triangle is predicting that factor of porosity is below 6%, consistent with fetched data interval geological analysis result; The loose point of square basic set is distributed in the bottom of plate, predicts the position that gas saturation is higher, and the loose point of rhombus basic set, in the top of plate, is predicted the position that water saturation is higher.

Figure 24 is rock physics plate and the M21 well lie geological data X plot based on fracture pore structure.The loose point of square drops between plate prediction factor of porosity 7%-13% with the loose point of rhombus, and the loose point of triangle is predicting that factor of porosity is below 7%, consistent with geological analysis result; The loose point of square basic set, in the bottom of plate, is predicted the position that gas saturation is higher, and the loose point of rhombus basic set, on the top of plate, is predicted the position that water saturation is higher.

Figure 25 was factor of porosity based on dissolution pore model of Met22 and Met3 well two-dimensional line seismic data and the gas saturation schematic diagram that predicts the outcome, Figure 26 was that Met22 and the gas saturation of Met3 well two-dimensional line seismic data based on dissolution pore model predict the outcome, Met22 well factor of porosity between 1860ms-1880ms reaches 10%, and gas saturation is higher.Met3 well factor of porosity between 1870ms-1890ms reaches 8%, and gas saturation is higher.

Figure 27 is Met22 borehole logging tool porosity curve and gas testing interval, Figure 28 is Met3 borehole logging tool porosity curve and gas testing interval, Met22 well is 67.5 ten thousand side/skies in the gas testing result of 2670-2679m interval, corresponding logging trace 1863-1867ms interval average pore is 12%, and result of log interpretation is gas-bearing formation.Met3 well is 76.5 ten thousand side/skies in the gas testing result of 2710-2730m interval, and corresponding logging trace 1879-1887ms interval average pore is 10%, and result of log interpretation is gas-bearing formation.The well logging factor of porosity of two mouthfuls of wells matches with prediction factor of porosity, and gas testing interval is all in prediction interval segment limit, and gas testing result matches with prediction gas saturation.

Figure 29 was Zen21 and the porosity prediction result of Met21 well two-dimensional line seismic data based on fractured model, Figure 30 was that Zen21 and the gas saturation of Met21 well two-dimensional line seismic data based on fractured model predict the outcome, Zen21 well factor of porosity between 1920ms-1940ms reaches 12%, only in zone of interest upper end, see that gassiness shows, gas saturation is lower.Met21 well factor of porosity between 1815ms-1845ms reaches 8%, has no gassiness and shows.

Figure 31 is Zen21 borehole logging tool porosity curve and gas testing interval, Figure 32 is Met21 borehole logging tool porosity curve and gas testing interval, Zen21 well is 0.96 ten thousand side/sky in the gas testing result of 2785-2805m interval, corresponding logging trace 1924-1932ms interval average pore is 13%, and result of log interpretation is air water layer.The well logging factor of porosity of this well matches with prediction factor of porosity, and gas testing interval is in prediction interval segment limit, and gas testing result matches with prediction gas saturation.Met21 well is dry layer in the gas testing result of 2730-2789m interval, and corresponding logging trace 1820-1840ms interval average pore is 5%, and result of log interpretation is poor gas-bearing formation.The well logging factor of porosity of this well is slightly less than prediction factor of porosity, and gas testing interval is in prediction interval segment limit, and gas testing result matches with prediction gas saturation.

In sum, gas reservoir Forecasting Methodology and the system of a kind of carbonate reservoir based on pore structure characteristic provided by the invention, set up petrophysical model have more conclusive, have more feature targetedly, can solve rock physics modeling and the gas saturation forecasting problem of different pore structures development belt in same study area.This scheme is the important expansion to existing rock physics modeling method, and its beneficial effect is mainly reflected in following aspect:

1, in rock skeleton modeling process, consider first the different pore structures of different sedimentary facies belt reservoir developments in same study area, for different pore structures development belt, set up respectively corresponding rock skeleton model.The conventional rock physics modeling method based on single pore texture is only applicable to pore texture and changes unconspicuous work area, and for the carbonate reservoir development area of strong nonuniformity, conventional modeling method exists applicability problem.

2, from geology thin slice, identify (geology angle) and core experiment measurement (experimental viewpoint) two aspects, for the division of pore structure characteristic provides foundation.Thin slice is identified the micropore structure feature that can observe directly rock from mirror; Core experiment can directly be measured contacting of physical properties of rock, fluid and wave response, and preferably sensitive parameter, for the prediction of gas reservoir quantification provides reliable basis.

One of ordinary skill in the art will appreciate that all or part of flow process realizing in above-described embodiment method, can carry out the hardware that instruction is relevant by computer program completes, described program can be stored in general computer read/write memory medium, this program, when carrying out, can comprise as the flow process of the embodiment of above-mentioned each side method.Wherein, described storage medium can be magnetic disc, CD, read-only store-memory body (Read-Only Memory, ROM) or random store-memory body (Random Access Memory, RAM) etc.

Those skilled in the art can also recognize that the various functions that the embodiment of the present invention is listed are to realize by hardware or software the designing requirement of depending on specific application and whole system.Those skilled in the art can, for every kind of specific application, can make in all sorts of ways and realize described function, but this realization should not be understood to exceed the scope of embodiment of the present invention protection.

In the present invention, applied specific embodiment principle of the present invention and embodiment are set forth, the explanation of above embodiment is just for helping to understand method of the present invention and core concept thereof; , for one of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention meanwhile.

Claims (16)

1. a gas reservoir Forecasting Methodology for the carbonate reservoir based on pore structure characteristic, is characterized in that, described method specifically comprises:

Gather the rock specimens of carbonate reservoir target reservoir section;

Described rock specimens is carried out to the evaluation of geology thin slice, obtain rock basic parameter, described rock basic parameter comprises rock composition, pore shape, face rate and sedimentary facies belt;

Described rock specimens is carried out to hole and ooze measurement, must arrive hole and ooze basic parameter, described hole is oozed basic parameter and is comprised factor of porosity, permeability and density;

According to described pore shape and sedimentary facies belt, carry out pore Structure Analysis, according to described rock basic parameter, hole, ooze basic parameter and the dry skeleton pattern of differential EFFECTIVE MEDIUM model construction rock;

The dry skeleton pattern of described rock is carried out to fluid substitution, generate rock physics plate;

Obtain the pre-stack seismic inversion data of carbonate reservoir;

Described pre-stack seismic inversion data and described rock physics plate are carried out to intersection, obtain the factor of porosity of described carbonate reservoir and predicting the outcome of gas saturation.

2. method according to claim 1, is characterized in that, the dry skeleton pattern of rock that oozes basic parameter and differential EFFECTIVE MEDIUM model construction according to described rock basic parameter, hole is:

$(1-y)\frac{{\mathrm{dK}}^{*}\left(y\right)}{\mathrm{dy}}=[K_2-K^{*}\left(y\right)]P^{(*2)}\left(y\right)$

$(1-y)\frac{{\mathrm{d\&mu;}}^{*}\left(y\right)}{\mathrm{dy}}=[{\mathrm{\&mu;}}_2-{\mathrm{\&mu;}}^{*}\left(y\right)]Q^{(*2)}\left(y\right)$

Wherein, K ₂for bulk modulus, the μ of hole ₂for the modulus of shearing of hole, y is the content of hole, and P, Q are geometry factor, starting condition K ^*(0)=K ₁, μ ^*(0)=μ ₁, K ₁for the bulk modulus of original mineral composition, μ ₁for the modulus of shearing of original mineral composition, K ^*for the bulk modulus of the dry skeleton pattern of rock, μ ^*for the modulus of shearing of the dry skeleton pattern of rock.

3. method according to claim 2, is characterized in that, described method also comprises:

Obtain the geologic report of carbonate reservoir;

Obtain the log data of carbonate reservoir;

Obtain the logging data of carbonate reservoir;

According to described geologic report, log data and logging data, the dry skeleton pattern of described rock is proofreaied and correct.

4. according to the method described in claim 1 or 3, it is characterized in that, the dry skeleton pattern of described rock carried out to fluid substitution, generate rock physics plate and specifically comprise:

The dry skeleton pattern of rock based on described, utilizes Biot-Rayleigh system of equations to carry out fluid substitution, generates the rock physics plate based on different pore structures.

5. method according to claim 4, is characterized in that, described Biot-Rayleigh system of equations is:

Wherein, u=[u ₁, u ₂, u ₃], $U^{\left(1\right)}=[U_1^{\left(1\right)},U_2^{\left(1\right)},U_3^{\left(1\right)}],U^{\left(2\right)}=[U_1^{\left(2\right)},U_2^{\left(2\right)},U_3^{\left(2\right)}]$ Represent respectively the space vector displacement of three kinds of components, subscript 1,2,3 represents three directions of vector space,

represent the local fluid deformation increment producing in the seismic event process of motivation, ξ is the displacement of fluid increment under seismic event extruding, b ₁, b ₂represent respectively containing water hole, containing the Biot dissipation factor in pore;

$e_{\mathrm{ij}}=\frac{1}{2}(\frac{{\&PartialD;u}_i}{\&PartialD;x_j}+\frac{{\&PartialD;u}_j}{{\&PartialD;x}_i}),{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(1\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(1\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(1\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(2\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(2\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(2\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},$

X ₁, x ₂with x ₃represent respectively the coordinate of three directions, φ ₁, φ ₂represent the absolute porosity of two class holes, the total porosity φ=φ of rock ₁+ φ ₂, φ ₁₀with φ ₂₀represent respectively the local factor of porosity in two regions, rock interior only contains a kind of skeleton, and saturated have two kinds of fluids, φ ₁₀=φ ₂₀=φ, ρ _f1and η ₁represent density and the viscosity of background phase fluid, R ₀represent bubble radius, κ ₁₀represent rock permeability, A, N, Q ₁, R ₁, Q ₂, R ₂for six Biot elastic parameters in double porosity media, ρ ₁₁, ρ ₁₂, ρ ₁₃, ρ ₂₂with ρ ₃₃represent five density parameters in double porosity media.

6. method according to claim 5, is characterized in that, described method also comprises:

Described rock specimens is carried out to ultrasonic measurement, obtain measurement result, described measurement result comprises dry velocity of longitudinal wave, dry shear wave velocity, moisture velocity of longitudinal wave and moisture shear wave velocity;

Measurement result based on described is determined preferred sensitive parameter;

According to described preferred sensitive parameter, from described rock physics plate, pick out preferred rock physics plate.

7. according to the method described in claim 1 or 6, it is characterized in that, described pre-stack seismic inversion data and described rock physics plate are carried out to intersection, and the factor of porosity and the predicting the outcome of gas saturation that obtain described carbonate reservoir specifically comprise:

From described pre-stack seismic inversion data, obtain p-wave impedance;

Using described p-wave impedance as transverse axis;

From described pre-stack seismic inversion data, obtain p-and s-wave velocity ratio;

Described p-and s-wave velocity is compared to the longitudinal axis;

Described rock physics plate is mapped in the coordinate system being comprised of described transverse axis, the longitudinal axis;

Adjust the coordinate of described rock physics plate, obtain the factor of porosity of target reservoir section and the predicting the outcome of gas saturation of described carbonate reservoir.

8. method according to claim 7, is characterized in that, described method also comprises:

Obtain the raw log data of carbonate reservoir;

According to described raw log data, determine well logging interpretation achievement;

According to described well logging interpretation achievement, predicting the outcome of described factor of porosity and gas saturation verified.

9. a gas reservoir prognoses system for the carbonate reservoir based on pore structure characteristic, is characterized in that, described system specifically comprises:

Rock specimens harvester, for gathering the rock specimens of carbonate reservoir target reservoir section;

Geology thin slice identification apparatus, carries out the evaluation of geology thin slice for the rock specimens to described, obtains rock basic parameter, and described rock basic parameter comprises rock composition, pore shape, face rate and sedimentary facies belt;

Measurement mechanism is oozed in hole, carries out hole ooze measurement for the rock specimens to described, must arrive hole and ooze basic parameter, and described hole is oozed basic parameter and comprised factor of porosity, permeability and density;

The dry skeleton member device of rock, for carrying out pore Structure Analysis according to described pore shape and sedimentary facies belt, oozes basic parameter and the dry skeleton pattern of differential EFFECTIVE MEDIUM model construction rock according to described rock basic parameter, hole;

Rock physics plate generating apparatus, carries out fluid substitution for the dry skeleton pattern of the rock to described, generates rock physics plate;

Pre-stack seismic inversion data acquisition facility, for obtaining the pre-stack seismic inversion data of carbonate reservoir;

Gas saturation prediction unit, for described pre-stack seismic inversion data and described rock physics plate are carried out to intersection, obtains the factor of porosity of described carbonate reservoir and predicting the outcome of gas saturation.

10. system according to claim 9, is characterized in that, the dry skeleton pattern of rock that the dry skeleton member device of described rock builds is:

$(1-y)\frac{{\mathrm{dK}}^{*}\left(y\right)}{\mathrm{dy}}=[K_2-K^{*}\left(y\right)]P^{(*2)}\left(y\right)$

$(1-y)\frac{{\mathrm{d\&mu;}}^{*}\left(y\right)}{\mathrm{dy}}=[{\mathrm{\&mu;}}_2-{\mathrm{\&mu;}}^{*}\left(y\right)]Q^{(*2)}\left(y\right)$

Wherein, K ₂for bulk modulus, the μ of hole ₂for the modulus of shearing of hole, y is the content of hole, and P, Q are geometry factor, starting condition K ^*(0)=K ₁, μ ^*(0)=μ ₁, K ₁for the bulk modulus of original mineral composition, μ ₁for the modulus of shearing of original mineral composition, K ^*for the bulk modulus of the dry skeleton pattern of rock, μ ^*for the modulus of shearing of the dry skeleton pattern of rock.

11. systems according to claim 10, is characterized in that, described system also comprises:

Geologic report acquisition device, for obtaining the geologic report of carbonate reservoir;

Log data acquisition device, for obtaining the log data of carbonate reservoir;

Logging data acquisition device, for obtaining the logging data of carbonate reservoir;

The dry skeleton pattern means for correcting of rock, for proofreading and correct the dry skeleton pattern of described rock according to described geologic report, log data and logging data.

12. according to the system described in claim 9 or 11, it is characterized in that, described rock physics plate generating apparatus specifically for:

The dry skeleton pattern of rock based on described, utilizes Biot-Rayleigh system of equations to carry out fluid substitution, generates the rock physics plate based on different pore structures.

13. systems according to claim 12, is characterized in that, described Biot-Rayleigh system of equations is:

Wherein, u=[u ₁, u ₂, u ₃], $U^{\left(1\right)}=[U_1^{\left(1\right)},U_2^{\left(1\right)},U_3^{\left(1\right)}],U^{\left(2\right)}=[U_1^{\left(2\right)},U_2^{\left(2\right)},U_3^{\left(2\right)}]$ Represent respectively the space vector displacement of three kinds of components, subscript 1,2,3 represents three directions of vector space,

represent the local fluid deformation increment producing in the seismic event process of motivation, ξ is the displacement of fluid increment under seismic event extruding, b ₁, b ₂represent respectively containing water hole, containing the Biot dissipation factor in pore;

$e_{\mathrm{ij}}=\frac{1}{2}(\frac{{\&PartialD;u}_i}{\&PartialD;x_j}+\frac{{\&PartialD;u}_j}{{\&PartialD;x}_i}),{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(1\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(1\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(1\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},{\mathrm{\&xi;}}_{\mathrm{ij}}^{\left(2\right)}=\frac{1}{2}(\frac{\&PartialD;U_i^{\left(2\right)}}{{\&PartialD;x}_j}+\frac{\&PartialD;U_j^{\left(2\right)}}{{\&PartialD;x}_i}){\mathrm{\&delta;}}_{\mathrm{ij}},$

X ₁, x ₂with x ₃represent respectively the coordinate of three directions, φ ₁, φ ₂represent the absolute porosity of two class holes, the total porosity φ=φ of rock ₁+ φ ₂, φ ₁₀with φ ₂₀represent respectively the local factor of porosity in two regions, rock interior only contains a kind of skeleton, and saturated have two kinds of fluids, φ ₁₀=φ ₂₀=φ, ρ _f1and η ₁represent density and the viscosity of background phase fluid, R ₀represent bubble radius, κ ₁₀represent rock permeability, A, N, Q ₁, R ₁, Q ₂, R ₂for six Biot elastic parameters in double porosity media, ρ ₁₁, ρ ₁₂, ρ ₁₃, ρ ₂₂with ρ ₃₃represent five density parameters in double porosity media.

14. systems according to claim 13, is characterized in that, described system also comprises:

Ultrasonic measuring device, carries out ultrasonic measurement for the rock specimens to described, measurement result, and described measurement result comprises dry velocity of longitudinal wave, dry shear wave velocity, moisture velocity of longitudinal wave and moisture shear wave velocity;

Preferably sensitive parameter device for sorting, determines preferred sensitive parameter for the measurement result based on described;

Rock physics plate device for sorting, for picking out preferred rock physics plate according to described preferred sensitive parameter from described rock physics plate.

15. according to the system described in claim 9 or 14, it is characterized in that, described gas saturation prediction unit specifically comprises:

Total wave impedance acquisition module, obtains p-wave impedance for the pre-stack seismic inversion data from described;

Transverse axis arranges module, for using described p-wave impedance as transverse axis;

P-and s-wave velocity, than acquisition module, obtains p-and s-wave velocity ratio for the pre-stack seismic inversion data from described;

The longitudinal axis arranges module, for described p-and s-wave velocity is compared to the longitudinal axis;

Mapping block, for being mapped to by described rock physics plate the coordinate system being comprised of described transverse axis, the longitudinal axis;

Gas saturation prediction module, for adjusting the coordinate of described rock physics plate, obtains the factor of porosity of target reservoir section and the predicting the outcome of gas saturation of described carbonate reservoir.

16. systems according to claim 15, is characterized in that, described system also comprises:

Log data acquisition device, for obtaining the raw log data of carbonate reservoir;

Well logging interpretation achievement determining device, for determining well logging interpretation achievement according to described raw log data;

The demo plant that predicts the outcome, for verifying predicting the outcome of described factor of porosity and gas saturation according to described well logging interpretation achievement.

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