# Method for geophysical prospecting for determining hydraulic conductivity and capacity of oil and gas productive porous collectors in three-dimensional inter-well space

FIELD: oil and gas industry.

SUBSTANCE: method includes performing three-dimensional seismic prospecting operations, drilling wells with taking of core, electric, radioactive, acoustic and seismic logging, testing of wells. On basis of drilling data and geophysical well research standard modeling seismic and well spectral-time images of oil-productive deposits and their spectral-time attributes are determined. On basis of data of surface three-dimensional seismic prospecting in area of wells standard experimental spectral-time images of oil and gas productive porous collectors and their volumetric spectral seismic attributes are determined on basis of use of spectral-time analysis of seismic prospecting data in goal range of recording and numeric estimation of its results. Following mutual correlation of values of hydraulic conductivity and capacity is performed on basis of drilling geophysical well research data with standard modeling seismic, well time-spectral attributes and volumetric spectral time attributes on basis of seismic prospecting data from area of wells. Optimal volumetric spectral seismic attributes are selected with greatest mutual correlation coefficients. Regression dependencies of optimal spectral seismic attribute are built, or same for complex attribute, with values of hydraulic conductivity and oil and gas productive porous collectors capacity according to drilling and geophysical well research data. Along all tracks of seismic time cube spectral-time analysis is performed and its numeric spectral-time parameterization on basis of optimal volumetric spectral seismic attribute, or complex attribute, with construction of attribute cubes and their following recalculation according to regression dependencies to hydraulic conductivity cubes and capacity cubes.

EFFECT: higher reliability, higher precision.

The invention relates to petroleum Geology and can be used for optimization of inception of exploration and production wells in the studied sites in areas of elevated values of hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs in complex three-dimensional data onshore 3D seismic survey, geophysical surveys and test wells, the study of the core.

There is a method of geophysical prospecting to determine reservoir properties neftegazoperspektivnyh deposits in the inter-well space, is selected as the closest analogue (Patent for invention №2210094), including drilling with coring, electrical, radioactive, acoustic and seismic logging, a study core, the conducting surface of the two-dimensional 2D seismic survey, as well as subsequent processing of the received information to determine the permeability and storage capacity of the target sediments according to the drilling and geophysical research wells (GIS), modeling of seismic reference spectral-temporal images (NWO) neftegazopromyslovogo interval of the section and their spectral-temporal parameters (SVP), experimental seismic reference in ITS district wells and SVP on the basis of spectral analysis (TFA) of seismic data, and if the natural enemy evaluation of its results, determined by the ratio of the energy spectra of high frequencies and large times to the energy spectra of low frequencies and smaller times, as well as product specific frequency and time spectral densities of the energy spectra in the frequency and time highs, with subsequent cross-correlation values of permeability and storage capacity by drilling data with reference SVP by seismic data in the area of wells, selection of optimal SVP with the highest cross-correlation coefficients (ICC) and building regression dependencies optimal SVP with values of permeability and storage capacity, followed by all seismic profiles continuously in the target interval recording SWANN, a determination of the optimal SVP their subsequent conversion by the regression dependences in the values of permeability and storage capacity at any point in the interwell space and mapping the contours of permeability and storage capacity, i.e. acquiring the two-dimensional result on a horizontal plane.

The disadvantages of this method are:

- conducting surface seismic profiles, i.e. two-dimensional 2D seismic data which do not take into account possible spatial seismic demolition and are characterized by a lack of detail, especially in complex environments and exploitation the m phase of drilling oil and gas facilities;

- loss of precision work happens at the stage of mapping the SVP, the permeability and storage capacity, because of the contour of great importance interpolation values SVP, permeability and storage capacity between profiles, the distance between which is almost always correlated with intervals of changes in filtration-capacitive properties of the target sediments;

- correlation between SVP and permeability is not always characterized acceptable CVR and stability.

There is also known a method of geophysical prospecting to determine the productivity of the oil reservoir in the interwell space (Patent for invention №2098851). In the known method, the productivity of the oil reservoir is determined on the basis of its correlation with water permeability, which, in turn, is determined using the average, constant values of the radius of the pore channels for each type of geologic section, and the effective specific capacity. Types of geologic section are identified and mapped on the basis of the SWAN seismic records, proatherogenic on drilling data and GIS (Patent for invention №2183335). The capacity of the reservoir, which is the product of the coefficient of porosity on the effective thickness is determined on the basis of its correlation from psevdoakusticheskuyu speeds on dannymasterson (Kopelevich E.A. and other parameter Definition the specific capacity of the reservoir in the interwell space. Geology of oil and gas, No. 8, M., 1988; Kopelevich E.A. Change the velocity of propagation of longitudinal waves in communication with the capacitive properties of the reservoir. Geology of oil and gas, No. 10, M, 1995).

The main disadvantages of the known methods are:

- the neglect of spatial seismic drift and lack of detail of 2D seismic;

- the assumption of the constancy of the radius of the pore channels in the development zones of the same type geological section;

- insufficient accuracy psevdoakusticheskuyu speeds, especially in environments with a low thickness neftegazoperspektivnyh sediments (<30 m);

- limited resolution and consequently the opportunity of application of the method only in case of significant differences psevdoakusticheskuyu speeds (>300-400 m/s).

Due to the above disadvantages can be errors in determining permeability, hydroconductivity and capacity neftegazoperspektivnyh layers and, as a consequence, optimal placement of wells and the increase in development costs of objects.

Technical problem on which this invention is directed, is to improve the accuracy, reliability and validity of the geological conditions of laying razvedok the s and production wells based on the definition of hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs in the three-dimensional inter-well space.

Method of geophysical prospecting to determine the hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs in the three-dimensional interwell space includes drilling with coring, electrical, radioactive, acoustic and seismic logging, the study of the core and the test wells, the subsequent conduct of the three-dimensional seismic survey 3D longitudinal waves by the method of common-depth-point (CDP).

On set of drilling data and GIS to determine the water permeability and the capacity neftegazoperspektivnyh porous reservoirs using well-known methods.

According to acoustic, seismic, radioactive logging, laboratory core studies are stiffness model of the target section in the wells, are computed synthetic seismic trace which are SWAN determine the model of the NWO and their spectral-temporal attributes (EAS). According to GIS define ITS target interval curves GIS and their borehole (vertical) IAS (Patent for invention №2201606).

According to the three-dimensional 3D seismic on the basis of the SWAN determine the reference experimental NWO and their volumetric spectral seismic attributes (OSS) in the area of the wells, corresponding to the time interval of the productive deposits.

Model, skvazhina the CBA and experimental OSS should be the same with CVR> of 0.75, which indicates a reasonable definition of NWO and the OSS according to the 3D seismic. At the higher CVR choose the best for a specific geologic conditions, the most reliable OSS.

ITS seismic data 3D - temporal cube, i.e. the dependence of seismic amplitudes from the three coordinates x, y, t - A=f(x,y,t) is a four-dimensional dependence of seismic amplitudes from the coordinates x, y, ƒ , t, or two cube dependencies A=f(x,ƒ ,t) and A=f(y,ƒ ,t), where ƒ - variable Central frequency spectra of seismic recording; t - axis times; x, y spatial coordinates.

ITS characterized quantitatively using OSS for each of the two cubes, with six cubes of OSS, i.e. three-dimensional dependence of OSS from three coordinates - OCCA=f(x,y,t).

The OSS in the amount of six attributes are determined by the energy (frequency along the frequency axis f) and temporary (on-axis time - t) spectra of the three-dimensional results, the SWAN cubes NWO.

OSSA along the frequency axis:

where

S(A^{2})(t) is the spectral density of the frequency power spectrum is proportional to the square of the amplitude of seismic records in the target time interval (Δ t);

ƒ_{n}- the initial (low) frequency spectrum at the level of 10% of its maximum;

ƒ_{to}- the final (high the frequency spectrum at the level of 10% of its maximum;

Thus, the OSS_{1}is the ratio of the energy of the high frequencies to the energy of low frequency energy of the frequency spectrum.

where Δ ƒ =ƒ_{to}-ƒ_{n};- weighted average frequency.

Thus, the OSS_{2}is the product of the specific power spectral density of the frequency spectrum by the average frequency.

where ƒ^{max}maximum frequency energy of a frequency spectrum at the level of 30-70% of its maximum.

Thus, the OSS_{3}is the product of the specific power spectral density of the frequency spectrum at the maximum frequency with the level selection (30-70%) of its definition.

OSSA-axis times:

where S(A^{2})(ƒ ), t_{n}, t_{to}that Δ t, t_{cp},- the same parameters of the energy spectrum, only along the axis of time (t).

Values of OSS axis t are determined by the target shift time interval (Δ t) on a constant selected value.

Thus, of the two cubes ITS possible to get a six cubes OCCA_{1-6}in the coordinates x, y, t.

All OSS are initially classified according to their structure in accordance with the principles of structurn the-structural interpretation (Structural-structural interpretation of seismic data. Mushin I.A., Fords LU, Kozlov E.A., Fatianov FI M.: Nedra, 1990).

Structure OCCA_{1}is that its main purpose is to identify and commit sequestrations ranks in the analyzed interval of the section and the assessment ratio on dynamic expressiveness, i.e. the shape of the signal, and consequently, its spectrum and OSSA, reflecting the combination of physical properties of the target interval of the section, due to including the structure of pore space or the size of the sectional area of the channels of the porous medium, which is filtered fluid, which is known to characterize the permeability and water permeability, but mainly the total porous volume, i.e. water permeability -

To_{CR}the permeability coefficient

h_{eff}effective thickness of the reservoir,

μ - viscosity fluid, the value for the field is constant.

The structure of the symmetric OCCA_{1}along the axis of the times - OSS_{4}- you can count on the detection of the direction of sedimentation, i.e. to assess the degree of progressivity or regressivity of the analyzed interval of the section, and hence the nature of changes in permeability and hydroconductivity collectors in depth.

OSS_{2}and the OSS_{3}characterize the analyzed online the tearing incision mainly on integral types of stratification and its severity,
i.e. the macro-, MIDI-, thin-layering, types of periodicity, rhythm, which is directly related to the volume of the void space or capacity.

OSS_{5}and the OSS_{6}having the same structure as that of the OCCA_{2}The OSS_{3}but defined by the axis of the times, can characterize the propagation characteristics of the layering (capacity) for the analyzed interval of the section.

Thus, the OSS by its physical and geological fact can be used to determine the hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs in the three-dimensional inter-well space.

The optimal, most reliable experimental reference of OSS in the area of wells, or integrated OSS representing convolution optimal OSS by famous modern algorithms cokriging or artificial neural networks, are correlated with the values of hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs by drilling data and GIS plotting of OSS^{opt}=f(K_{CR}·_{}h_{eff}and the OSS^{opt}=f(K_{p}·_{}h_{eff}), where K_{p}the porosity coefficient.

When values of CVR>0.75 in Cuba optimal or comprehensive OSS translated into cubes values hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs in the coordinates x, y, t.

Still the way this proposal allows to determine the water permeability and the capacity neftegazoperspektivnyh porous reservoirs at any point in the three-dimensional inter-well space.

This provides a sharp decline in the cost of subsequent drilling exploration and production wells.

Method of geophysical prospecting to determine the hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs in the three-dimensional inter-well space, including land seismic surveys, drilling with coring, electrical, radioactive, acoustic, seismic, logging, well testing, and judgment on the received data hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs, characterized in that the inter-well space spend three-dimensional 3D seismic work, drilling data and GIW define a reference model of seismic and borehole spectral-temporal images neftegazoperspektivnyh collectors and their spectral-temporal attributes, and according to the three-dimensional 3D seismic in the area of wells determine the reference experimental spectral-temporal images neftegazoperspektivnyh porous reservoirs and their volumetric spectral seismic attributes based on the application of SP is Strelna-temporal analysis of 3D seismic data and geophysical studies of wells in the target recording interval and quantitative evaluation of its results, represents the ratio of the energy spectra of high frequencies and large times to the energy spectra of low frequency and small times, and also product specific frequency spectral energy densities of the frequency spectrum on average and maximum rate and product specific time spectral densities temporary energy spectrum on the average and maximum time, with subsequent cross-correlation values of hydroconductivity and capacity according to the drilling and geophysical surveys of the wells with the standard model of seismic and borehole spectral-temporal attributes and three-dimensional spectral seismic attributes on 3D seismic data in the area of wells; the choice of the optimal volumetric spectral seismic attributes with the highest values of the coefficients cross-correlation and building regression dependencies of the optimal reference volumetric spectral seismic attributes, or complex attribute, with values of hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs by drilling data and well logging; then all the routes temporary seismic cube in the target recording interval hold time-frequency analysis and its quantitative spectral-temporal is parametrization optimal volumetric spectral seismic attributes, or complex attribute, build cubes attributes and their subsequent conversion by the established regression dependencies in Cuba the hydroconductivity and capacity, i.e. the definition of hydroconductivity and capacity neftegazoperspektivnyh porous reservoirs at any point in the three-dimensional inter-well space.

**Same patents:**

FIELD: oil and gas industry.

SUBSTANCE: method includes performing three-dimensional seismic prospecting operations, drilling wells with taking of core, electric, radioactive, acoustic and seismic logging, testing of wells. On basis of drilling data and geophysical well research standard modeling seismic and well spectral-time images of oil-productive deposits and their spectral-time attributes are determined. On basis of data of surface three-dimensional seismic prospecting in area of wells standard experimental spectral-time images of oil and gas productive porous collectors and their volumetric spectral seismic attributes are determined on basis of use of spectral-time analysis of seismic prospecting data in goal range of recording and numeric estimation of its results. Following mutual correlation of values of hydraulic conductivity and capacity is performed on basis of drilling geophysical well research data with standard modeling seismic, well time-spectral attributes and volumetric spectral time attributes on basis of seismic prospecting data from area of wells. Optimal volumetric spectral seismic attributes are selected with greatest mutual correlation coefficients. Regression dependencies of optimal spectral seismic attribute are built, or same for complex attribute, with values of hydraulic conductivity and oil and gas productive porous collectors capacity according to drilling and geophysical well research data. Along all tracks of seismic time cube spectral-time analysis is performed and its numeric spectral-time parameterization on basis of optimal volumetric spectral seismic attribute, or complex attribute, with construction of attribute cubes and their following recalculation according to regression dependencies to hydraulic conductivity cubes and capacity cubes.

EFFECT: higher reliability, higher precision.

FIELD: oil and gas industry.

SUBSTANCE: method includes performing three-dimensional seismic prospecting operations, drilling wells with taking of core, electric, radioactive, acoustic and seismic logging, testing of wells. In inter-well space seismic prospecting operations are performed by three-dimensional longitudinal waves according to deep point method. On basis of drilling data and geophysical well research standard modeling seismic and well spectral-time images of oil-productive deposits and their spectral-time attributes are determined. On basis of data of surface three-dimensional seismic prospecting in area of wells standard experimental spectral-time images and their volumetric spectral seismic attributes are determined on basis of use of spectral-time analysis of seismic prospecting data in goal range of recording and numeric estimation of its results. Following mutual correlation of values of hydraulic conductivity and coefficients of oil productiveness is performed on basis of drilling geophysical well research data with standard modeling seismic, well time-spectral attributes and volumetric spectral time attributes on basis of seismic prospecting data. Optimal volumetric spectral seismic attribute is selected with greatest mutual correlation coefficient. Regression dependencies of optimal spectral seismic attribute are built, or same for complex attribute, with value s of hydraulic conductivity and oil-productiveness coefficient of porous collectors according to drilling and geophysical well research data. Along all tracks of seismic time cube spectral-time analysis is performed and its numeric spectral-time parameterization on basis of optimal volumetric spectral seismic attribute, or complex attribute, with construction of attribute cube and its following recalculation according to regression dependencies to hydraulic conductivity cubes and oil productiveness cubes.

EFFECT: higher reliability, higher precision.

FIELD: oil and gas industry.

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EFFECT: higher reliability, higher precision, higher efficiency.

FIELD: oil and gas industry.

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EFFECT: higher reliability, higher precision.

FIELD: oil and gas industry.

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EFFECT: higher reliability, higher precision.

FIELD: oil and gas industry.

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EFFECT: higher reliability, higher precision, higher trustworthiness, higher efficiency.

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SUBSTANCE: method comprises exciting seismic vibration by means of a seismic source, generating simultaneously electric field by means of at least two electrodes, recording seismic vibration at least once when current is supplied to the electrodes and at least once when electric power is not supplied to them, producing the difference of seismic records obtained in the presence and absence of electric field, and detecting anomalous phenomena from the variation of the amplitude of reflected waves of seismic and seismic-electric fields.

EFFECT: enhanced precision and reduced cost of prospecting.

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SUBSTANCE: method involves performing seismic exploration; drilling wells; determining reflection horizon seam depth on the base of drilling data; obtaining dependence of above seam depth as a function of relief altitude and determining interval velocity of upper non-uniform layer for following subsurface geologic imaging.

EFFECT: increased accuracy.

FIELD: geophysics.

SUBSTANCE: in accordance to method by transformation of excited and registered wave fields, amplitude-frequency and transfer characteristics of deposits of hydrocarbon resources are formed along lateral line and below face of control well, which are used to determine position and depth of oil-gas deposits. After transformation and comparison of frequency characteristics of longitudinal and transverse resilient oscillations, character of saturation and filtering-capacity properties of oil-gas deposits are determined.

EFFECT: higher efficiency, higher trustworthiness.

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EFFECT: increased efficiency of aerial deposit extend and age prediction.

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