37 results about "Cross-plot" patented technology

This invention discloses a method utilizing nuclear magnetic resonance double-T E The method for classifying water flooding levels in well logging is as follows: First, the transverse relaxation rate of nuclear magnetic resonance (NMR), the geometric mean of the mobile fluid portion of the T2 spectrum, and the double T2 spectrum are calculated sequentially using NMR logging data. E The geometric mean difference of the mobile fluid portion of the T2 spectrum was measured. Then, the porosity of different components was obtained by inversion of echo data under long waiting times and short echo intervals. Finally, the percentage content of macroporous components in the total porosity was plotted against the T2 spectrum. E Cross plot of geometric mean difference of the mobile fluid portion of T2 spectrum and plotting of array induced resistivity AT90 and double T E The cross plot of the geometric mean difference of the mobile fluid portion of the T2 spectrum is measured to identify the flooding level of the flooded layer: unflooded layer, low flooded layer, medium flooded layer, and high flooded layer.

The invention provides a method and device for predicting a thin reservoir based on seismic data, and relates to the technical field of oil-gas exploration and development, and the method comprises the steps: S1, obtaining actual drilling data, seismic data and geological comprehensive analysis data of a target interval; s2, extracting a wavelet dominant frequency of seismic data of a target layer section, establishing a cross-correlation function of two signals of a seismic record waveform and a synthetic record waveform, obtaining synthetic record drift time, calculating an attenuation coefficient Qf by using the record drift time and the seismic record time, and completing high-precision synthetic record calibration based on a time-frequency attenuation relationship rule; and S3, drawing a cross plot of the sand body thickness and the impedance value, determining a wave impedance identification threshold, and outputting a seismic wave impedance inversion profile of the target layer and a sand body thickness map through threshold value constraint. According to the method, reservoir plane distribution and spatial distribution rules can be depicted finely, thin reservoir sandstone prediction precision and accuracy are improved, and risks caused by drilling are reduced.

The invention discloses a deep coal seam coal phase type division method considering industrial component contents, and relates to the technical field of unconventional reservoir exploration and development. The method comprises the following steps: obtaining a target coal sample in a research area, respectively carrying out industrial component testing and submicroscopic component identification and determination on the target coal sample, and calculating coal phase parameters according to the actual submicroscopic component content; performing correlation analysis on the coal phase parameters, and discussing the repeatability of representing the coal phase characteristics under different coal phase parameters; key coal phase parameters are screened out through correlation among the coal phase parameters, and coal phase basic types are divided out through a coal phase parameter cross plot; finally, the content difference of ash, moisture, volatile components and fixed carbon in industrial components in the coal phase and the influence on micropores are considered, the type of the coal phase is further refined, subsequent construction of a deep coal seam coal phase type division method is facilitated, and a good data basis and a type division thought are provided for the deep coal seam coal phase type division method.

The invention belongs to the technical field of oil exploration and development, and discloses a method for identifying volcanic rock weathering crust and interior periods based on multiple seismic attributes, which comprises the following steps: determining a logging chart division boundary; a seismic data volume corresponding to the logging data is read, a cross plot is drawn, and a seismic data volume correction formula is obtained through linear fitting; correcting the seismic data volume of the research area; dividing the corrected data volume through a logging plate division boundary to obtain a first probability volume P1; determining an impedance plate division boundary; performing inversion to obtain an inversion resistance body; dividing the inversion impedance body according to an impedance plate division boundary to obtain a second probability body P2; performing weighted calculation on the P1 and the P2 to obtain a volcanic rock interior period identification parameter body P3; and establishing a recognition plate by using the P3, and determining a division boundary of the recognition plate to obtain a volcanic rock interior period recognition probability body P4. According to the method, well-seismic data unification is realized, and the weathering crust and the inner curtain period can be effectively identified in combination with an impedance inversion data body prediction result.

The invention provides a method and device for predicting the total organic carbon content of shale, and the method comprises the steps: selecting shale samples from a plurality of wells for testing, obtaining the total organic carbon content and the wave impedance value of the shale, carrying out the correlation analysis of the total organic carbon content and the wave impedance value, and selecting a target well with the correlation greater than a preset threshold value; in the target well, shale total organic carbon content and wave impedance data from wells in different layers in different blocks are obtained; drawing a cross plot of the total organic carbon content and the wave impedance of different layers of different blocks; constructing a quantitative relational expression between the total organic carbon content and the wave impedance of different blocks and different layers on the basis of the cross plot; acquiring wave impedance data of a to-be-predicted well, and predicting shale distribution according to the wave impedance data; and substituting the wave impedance data of the shale distribution area into a quantitative relational expression corresponding to the block and the horizon of the shale distribution area, and predicting the total organic carbon content of the shale. According to the method, the total organic carbon content of the shale can be predicted more accurately.

The invention provides a reservoir natural commissioning capability qualitative evaluation method and device, and solves the problem that whether a reservoir can be naturally commissioned or not cannot be judged by using logging data. Comprising the following steps: acquiring logging curves and logging gas logging data of all logging wells in a target area; drawing a cross plot based on the logging curve of the logging well, and dividing a first area where a reservoir capable of being put into production naturally is located in the cross plot; a first chart is drawn based on logging gas logging data of logging, and a second area where a reservoir capable of being put into production naturally is located is counted in the first chart; obtaining a first seepage capacity parameter and a first oil-gas-bearing property parameter based on a logging curve of the reservoir to be evaluated, plumbing the seepage capacity parameter and the oil-gas-bearing property parameter into the cross plot, and judging whether the plumbing point is located in the first area or not; and if yes, drawing a second chart based on the gas logging data of the to-be-evaluated reservoir, judging whether a preset number of data points in the second chart fall in the second area, and if yes, determining that the to-be-evaluated reservoir is a reservoir capable of being put into production naturally.

The invention discloses an earthquake comprehensive prediction method for shallow complex oil and gas type identification, and the method comprises the steps: building a rock physical model suitable for a research region for fluid replacement through the statistics of drilled well data in the research region on the basis of an AVO technology; then, a P-G cross plot is made by using a reflection coefficient approximation formula in combination with the logging data and the fluid replacement data; performing linear fitting on the discrete sample points according to different fluid types, determining the positions of a waterline, an oil line and a gas line, and defining the fluid types in different areas; and finally, qualitatively determining the fluid property according to the position distribution of the target layer sample points in the research area on the template. According to the method, seismic data and logging data are comprehensively utilized, the AVO template suitable for a research area is established, the requirement for logging data is lowered, fluid types can be rapidly identified before drilling only through elastic information of strata, meanwhile, the transverse and longitudinal distribution range of oil and gas is predicted, efficiency and identification accuracy are greatly improved, and the method is suitable for popularization and application. And meanwhile, the production cost is greatly reduced.

Provided are a fluid identification method and system, a terminal device, and a machine-readable storage medium, belonging to the field of petroleum exploration. The method comprises: determining a study sample logging curve, a gas logging curve and drilling detection parameters; on the basis of the study sample logging curve, establishing a shallow resistivity and deep resistivity cross plot, and identifying water from among unknown fluids; using the gas logging curve to establish a derived parameter cross plot; using the study sample logging curve and the drilling detection parameters to establish a semi-quantitative evaluation chart of CO2 content based on density porosity and neutron porosity, and a semi-quantitative evaluation chart of CO2 content based on density porosity and porosity difference; on the basis of the derived parameter cross plot, the semi-quantitative evaluation chart of CO2 content based on density porosity and neutron porosity, and the semi-quantitative evaluation chart of CO2 content based on density porosity and porosity difference, identifying CO2, condensate gas and oil in the unknown fluids. By means of the provided method, unknown fluids can be accurately identified, and logging interpretation evaluation accuracy is improved.

The invention relates to a shale lithofacies identification method based on a three-dimensional cross plot of multiple logging parameters. The method mainly solves the problem that shale lithofacies are difficult to identify by using a conventional logging curve. The method comprises the following steps: step 1, dividing shale lithofacies types in a target interval of a research area; 2, selecting a standard lithofacies sample; according to the logging response characteristics of the shale lithofacies in the target interval of the research area, a logging curve sensitive to the shale lithofacies is preliminarily selected; a Wilks criterion is utilized to screen a logging curve suitable for shale lithofacies identification; and 3, based on the screened logging curve, processing logging data participating in shale lithofacies division by utilizing a Fisher discrimination method, and determining the distribution range of various shale lithofacies in a three-dimensional space by utilizing a three-dimensional intersection method, so as to perform logging identification on the shale lithofacies. The method is wide in application range and high in applicability, and has important significance on shale oil reservoir evaluation.

The invention belongs to the technical field of formation pore pressure acquisition, and discloses a pore pressure acquisition method and system based on a depth trend line and formation factors, and the method comprises the steps: collecting well leakage, gas cut and overflow in a drilling process, and re-pressing and static pressure data in an oil testing process, and fitting a regression pressure trend line; drawing an engineering pore pressure geological factor interpretation read map, reading interval transit time and density logging values, and calculating formation factors; forming a pressure factor linearly related to the formation pore pressure by combining the regression pressure trend line and the formation factor; and drawing a formation pore pressure-pressure factor cross plot, carrying out linear regression fitting, and calculating the equivalent density of the formation pore pressure. According to the method, various pressure data (such as well leakage, gas cut, overflow and re-pressure and static pressure data in the oil testing process) in the drilling process are collected, the data are used for logarithmic regression fitting, and the obtained pressure trend line can more accurately reflect the change trend of the formation pore pressure along with the depth.

The invention discloses a method for calculating the effective carbon dioxide storage capacity of a constant-volume depleted gas reservoir. The method comprises the following steps: collecting original geological reserves of a target gas reservoir, production dynamic data, original formation pressure and temperature of the gas reservoir, high-pressure physical property analysis and constant-volume depletion test data; establishing a relational expression between the pseudo-pressure and the accumulated natural gas equivalent yield in the corresponding period, then drawing a cross plot of the material balance relationship in the production stage of the target gas reservoir, and if the accumulated natural gas equivalent yield when the pseudo-pressure is equal to 0 is consistent with the original formation natural gas reserves, determining that the gas reservoir is a constant-volume depleted gas reservoir; inquiring a CO2 deviation factor under the pressure and temperature of the original formation of the gas reservoir from CO2 injection, and calculating a mixed gas deviation factor under the pressure of the original formation of the gas reservoir from CO2 injection by utilizing the final recovery degree of the gas reservoir; calculating the injectable amount of CO2 injected from the exhausted gas reservoir to the original formation pressure of the gas reservoir; and calculating the CO2 effective storage capacity of the depleted gas reservoir. According to the method, the effective carbon dioxide storage capacity of the constant-volume exhausted gas reservoir can be reliably calculated.

The invention relates to the technical field of oil exploration, and discloses an inter-coal oil-bearing reservoir prediction method and device, a medium and computing equipment. The method comprises the steps that single well curve characteristic analysis is carried out, qualitative analysis is carried out on curves of sound waves, resistivity, porosity and natural potential, and the characteristics of the oil-bearing reservoir are determined; carrying out quantitative analysis on the density and the gamma curve, and carrying out curve fitting; the fitted curve is optimized, and the influence of the coal seam is eliminated; establishing a favorable reservoir indication curve and a sound wave time difference cross plot, carrying out quantitative analysis on the oil-bearing reservoir, and dividing the interval of the oil-bearing reservoir to distinguish the oil-bearing reservoir; well-seismic calibration is carried out, and a coal seam oil-bearing reservoir removal initial model is established based on the favorable reservoir indication curve; and based on the coal seam-removed oil-bearing reservoir initial model, carrying out oil-bearing reservoir prediction, and drawing an oil-bearing reservoir planar graph and an oil-bearing reservoir profile graph. According to the method, the influence of the coal seam is eliminated, the applicability to the oil-containing reservoir between the coal is improved, and the distribution condition of the oil-containing reservoir is conveniently and accurately predicted.

The invention provides a sandstone reservoir identification method based on common constraint of three elements. The sandstone reservoir identification method comprises the following steps: establishing an isochronous stratigraphic framework according to a seismic interpretation profile, a drilling lithology comprehensive histogram and logging curve data of a research area; under the isochronous stratigraphic framework, sedimentary microfacies identification mark establishment and sedimentary microfacies division are carried out according to drilling core data and logging curve data, and the sedimentary microfacies distribution range of a research area is determined; in the sedimentary microfacies distribution range, according to well drilling core data, well logging curve data and well drilling coring data, sand body types are identified, and sand body distribution conditions are determined; drawing a cross plot according to various logging curves; establishing a sedimentary microfacies-sand body distribution-logging intersection identification sandstone reservoir scheme; and counting the thickness of the sandstone reservoir according to the sandstone reservoir, and drawing a thickness contour map of the sandstone reservoir. The sandstone reservoir can be identified more efficiently and clearly, and the prediction method has universality.

This invention relates to the technical field of reservoir oil-bearing evaluation methods, and discloses a qualitative evaluation method and system for the oil-bearing properties of heterogeneous reservoirs. The qualitative evaluation method for the oil-bearing properties of heterogeneous reservoirs introduces the natural gamma coefficient of variation V. GR This method characterizes the heterogeneity of reservoirs caused by mudstone interlayers. By combining arrayed induced resistivity (RT) and natural gamma (GR) to establish cross plots, the impact of reservoir heterogeneity on oil-bearing evaluation is reduced to some extent, thereby improving the reliability of oil-bearing evaluation for heterogeneous reservoirs. In addition, through actual data statistics and cross plot analysis, combined with well types and sand body structure models, this method establishes an oil-bearing evaluation standard table, making the method highly operable and practical in actual applications. This improves the reliability of oil-bearing evaluation for heterogeneous reservoirs and provides methodological support for reservoir development and reserve upgrading.

The invention relates to the technical field of geophysical well logging interpretation, in particular to a compact sandstone reservoir complex fluid self-adaptive identification method and device, and the method comprises the steps: analyzing the relation between different fluid types and lithology, physical property, pore structure and brittle reservoir characteristic parameters in a histogram and cross plot mode, and qualitatively determining the main control elements of the fluid type difference; constructing required quantization parameters according to the main control elements; performing normalization processing on the logging curve and the quantization parameters; selecting sensitive parameters from the existing logging curve and the constructed quantization parameters by using a spider diagram; fusing the multiple parameters by using a principal component analysis method, and constructing fluid type master control elements; establishing a label database according to the constructed index and the corresponding fluid type; and training and self-adaptive explanation of a complex fluid identification model are carried out. According to the method, the recognition precision of the complex fluid of the compact sandstone reservoir is improved, and a geological foundation is laid for subsequent dessert evaluation and target optimization.

The invention provides an oil source comparison method and equipment based on multivariate statistical analysis, and relates to the technical field of petroleum geological prospecting, and the method comprises the steps: carrying out the secondary change analysis of an oil source type set, and obtaining a rejected oil source type set; selecting a biomarker compound parameter set according to the removed oil source type set; obtaining a clustering pedigree diagram through the biomarker compound parameter set; obtaining a principal component load diagram through the biomarker compound parameter set; a key parameter set is obtained through the principal component load graph, factor scores are obtained through calculation of the key parameter set, and a factor score cross plot is constructed through the factor scores; and constructing a discriminant analysis chart through the clustering pedigree chart and the factor score cross plot. According to the method, the relation among the indexes in the main components is fully analyzed, the oil source relation is analyzed in a multi-dimensional mode, effective oil source comparison can be carried out under the complex background of development of multiple sets of hydrocarbon source rocks, and the method has the advantages of being high in comparison analysis efficiency, convenient to use and high in precision.

The invention relates to a clastic rock high-quality reservoir identification method based on rotation coordinate transformation. The clastic rock high-quality reservoir identification method comprises the following steps: S1, collecting reservoir characteristic parameters of a clastic rock reservoir and a multi-index data set of a logging curve; s2, according to the multi-index data set, selecting a combination of a plurality of indexes to construct an identification index variable; s3, based on the constructed identification index variables, constructing a core index set by using a main factor analysis method; s4, according to indexes in the core index set, initial rotation coordinates are constructed; s5, based on a rotation coordinate conversion equation, converting the numerical values of the indexes in the original coordinate system into numerical values in a new coordinate system; s6, constructing a secondary cross plot according to the original coordinate system and the new coordinate system; s7, evaluating the secondary cross plot, carrying out discrimination analysis on the discrimination effect, and adjusting the rotation coordinates according to the discrimination analysis result; and S8, according to the finally adjusted secondary cross plot, dividing the reservoir type and the spatial distribution range of the clastic rock reservoir.

The invention relates to a method for qualitatively identifying geological sweet spots of a shale reservoir, and belongs to the technical field of oil and gas development. The method specifically comprises the following steps: selecting a standard well in a research area, and describing dessert characteristics through special logging data and test analysis data of geochemical logging in combination with formation testing, yield and rock core display; for coring wells with complete logging series in a research area, a sensitive curve cross plot is formed by combining special logging data, test analysis data, oil testing, yield and rock core display description with common scale conventional logging curves, and sweet spot conventional curve response characteristics are qualitatively described through the sensitive curve cross plot; and constructing a dessert factor, analyzing logging response characteristics to establish a dessert standard, selecting key coring wells with complete logging series in a research area for verification, and determining the goodness of fit of the method. The method solves the problem that shale reservoir dessert recognition is difficult, the whole method is high in operability, and the method has important scientific guiding significance in old well review, unconventional oil and gas resource exploration and the like.

The application discloses a stratum boundary identification method and device, electronic equipment and a storage medium. The stratum boundary identification method comprises the following steps: determining a target survey area, obtaining historical logging data corresponding to the target survey area, correcting the historical logging data to obtain corrected logging data, wherein the corrected logging data comprises corrected phosphorus content data; determining a boundary depth range based on the corrected phosphorus content data, and determining a target survey value corresponding to each candidate boundary depth in the boundary depth range; determining a target cross plot based on the target survey value, and determining a target stratum boundary based on the target cross plot. Based on the technical scheme of the embodiment of the application, the stratum boundary identification efficiency can be improved and the stratum boundary identification cost can be reduced on the basis of accurately identifying the stratum interface. Based on the technical scheme of the embodiment of the application, the efficiency and accuracy of the stratum boundary identification are improved, and the cost of the stratum boundary identification is reduced.

The invention belongs to the technical field of rock mass detection, and provides a basement granite distribution range prediction method, system and device and a medium, and the method comprises the steps: obtaining the logging data of a basement layer section of a research area; establishing a lithology identification graph according to the obtained logging data of the substrate layer section of the research area; the lithology identification graph is an MN cross plot, and M is the slope of a straight line on the sound wave and density cross plot; n is the slope of a straight line on the neutron and density cross plot; determining M value and N value ranges of granite; in the MN cross plot, the area belonging to the range of the M value and the N value of the granite is the granite distribution area.

The invention discloses a porous carbonate reservoir evaluation method, system, equipment and medium, and the evaluation method constructs a reservoir elasticity factor K and a quality factor F which can reflect the quality of a carbonate reservoir, draws a cross plot through the reservoir elasticity factor K and the quality factor F, determines the value range of the reservoir, and obtains the value of the carbonate reservoir. Using a power formula fitting method to obtain expressions of the reservoir quality factor formula about speed and density, finally substituting the expressions into a reservoir quality factor data volume and a reservoir elastic factor data volume, and finally performing assignment to obtain a high-quality reservoir for predicting distribution of the high-quality reservoir in the seismic work area; the invention further comprises a system, equipment and a medium for implementing the method. According to the method, the reservoir quality of the porous carbonate rock can be quantitatively evaluated, and then a high-quality exploration and development target is optimized.

The invention relates to the technical field of oil-gas exploration and development, and particularly discloses a seismic-electric fusion reservoir fluid identification method, which comprises the following steps of: firstly, obtaining a three-dimensional seismic horizon, further obtaining a geological framework of a work area according to the three-dimensional seismic horizon, and inverting electromagnetic data to obtain an inversion resistivity profile; and the inversion resistivity of the target stratum of the work area is obtained by combining the geological framework and the inversion resistivity profile. And based on the resistivity fluid type cross plot, the fluid type of the target layer can be identified by the inversion resistivity of the target layer. Compared with a traditional fluid identification technology, the reservoir fluid identification method integrates the spatial distribution depiction advantage of well-to-seismic combination and the advantage that an electrical method is sensitive to fluid, is not limited to identification of the fluid at the drilling position, can accurately identify the fluid of each reservoir in a work area, and is high in fluid identification accuracy, large in identification range and easy to operate.

The invention discloses a shale lithofacies recognition method, device and equipment based on a cross plot technology and a medium, and relates to the technical field of petroleum and natural gas exploration and development, and the method comprises the steps: obtaining natural gamma data, resistivity data and interval transit time data of a to-be-recognized shale lithofacies; drawing a lithology intersection curve based on the natural gamma data and the resistivity data by adopting a cross plot technology, and analyzing the lithology intersection curve to obtain shale lithology; drawing and analyzing a shale organic characteristic intersection curve and a shale structure intersection curve based on the resistivity data and the interval transit time data to obtain shale organic characteristics and a shale structure; comprehensively analyzing the shale lithology, the shale organic characteristics and the shale structure by utilizing the lithology intersection curve, the shale organic characteristic intersection curve and the shale structure intersection curve to obtain an analysis result; and identifying the shale lithofacies to be identified according to the analysis result to obtain a shale lithofacies identification result. The shale lithofacies can be comprehensively identified, and the shale lithofacies identification accuracy and efficiency are improved.

The invention discloses a sand-to-ground ratio prediction method and system for constructing a virtual well optimization variation function by using seismic attributes, and the method comprises the steps: determining a lithology division critical value based on the intersection analysis of a gamma curve and a density curve of a real drilling well, carrying out the statistics of the accumulated thickness of sandstone and mudstone of each layer section, and calculating the sand-to-ground ratio data of the real drilling well; extracting seismic attributes from the seismic data of the target area to generate a seismic attribute plane graph; associating well point sand-to-ground ratio data with seismic attribute values to draw a cross plot, constructing a linear regression relational expression, calculating a sand-to-ground ratio determination coefficient of seismic attributes, and screening to obtain sensitive seismic attributes; designing a virtual well network based on the sensitive seismic attributes and assigning the sensitive seismic attributes to form a virtual well data set; on the basis of the virtual well data set, variation function graphs under different well distances are drawn, and optimized variation function parameters are obtained through variation function graph statistics; and based on the optimized variation function parameters, adopting a Gaussian random function algorithm to generate a sand-to-ground ratio plane distribution diagram. Accurate prediction of the sand-to-land ratio of the reservoir is realized.

The invention provides an oil layer dessert identification method and device fusing wavelet time-frequency analysis and deep learning and a medium, and belongs to the field of oil-gas exploration and development. Comprising the following steps that logging data are collected, measurement data of logging curves changing along with the depth and an oil testing and production testing result data set of corresponding layers are established, standardized preprocessing is conducted on original logging data, and a cross plot of different logging curves is drawn; carrying out sensitivity analysis on the logging curve by utilizing the cross plot, carrying out wavelet decomposition after carrying out normalization processing on the sensitive logging curve, and determining an optimal wavelet function and an optimal decomposition scale; a BiLSTM-FCNN oil layer sweet spot recognition model is constructed and trained, sensitive logging curve data is processed by adopting the determined optimal wavelet function and the optimal decomposition scale and then input to the trained model, and an oil layer sweet spot recognition result is output; according to the method, the problem of separation of noise and effective features in original data signals is solved, and the generalization ability of the model under complex geological conditions is improved.

The invention discloses a formation volume density prediction method based on lithology identification, and relates to the technical field of petroleum drilling and completion, and the method comprises the following steps: S1, collecting well logging data of a drilled well in a target work area; s2, obtaining a porosity difference value between the density porosity and the neutron porosity by using the logging data; s3, drawing a cross plot of the logging stratum volume density and the porosity difference value, and identifying the lithology of sandstone and mudstone by using the cross plot; s4, drawing a logarithmic cross plot according to sandstone and mudstone lithology identification results, and fitting on the logarithmic cross plot to obtain a sandstone and mudstone volume density prediction formula logarithmic form; s5, obtaining a sandstone and mudstone volume density prediction formula according to the logarithmic form of the sandstone and mudstone volume density prediction formula; and S6, predicting the sandstone and mudstone volume density of a subsequent new drilled well in the target work area by using a sandstone and mudstone volume density prediction formula. The stratum density prediction precision is improved, and the method has important practical significance on physical property analysis of a subsequent new drilling well stratum in a target work area.

The invention belongs to the technical field of exploration, and particularly relates to a bedrock lithology identification method based on conventional logging and element logging multi-parameter fusion, which fully considers the response characteristics of a conventional logging curve and an element logging curve of a bedrock, comprehensively constructs a lithology conventional curve identification index LITHcom through natural gamma, density, neutrons and the like, and identifies the lithology of the bedrock according to the lithology conventional curve identification index LITHcom. The method comprises the following steps: comprehensively constructing a lithologic element identification index LITHECS by using four element curves of calcium, iron, silicon and titanium, establishing a cross plot by using the two constructed lithologic element identification indexes, and establishing a bedrock lithologic identification standard in combination with rock core analysis and imaging data. Through verification of core analysis data, fusion parameters are introduced for bedrock lithology identification, accurate identification of the whole well section of the bedrock is realized, the lithology identification precision of the bedrock is improved, and the lithology of the dominant reservoir of the bedrock can be determined in combination with a gas test result.

The invention relates to a method for optimizing the reasonable oil pipe size of an injection-production well of a weak water drive sandstone oil and gas reservoir, which comprises the following steps of: 1, determining binomial productivity equation coefficients A and B of a gas well, and establishing a productivity equation; and 2, analyzing and determining the critical sand production pressure difference during gas production of the injection-production well of the target gas storage. And 3, establishing a binomial function relationship between the formation pressure and the accumulative gas production amount. 4, according to the established binomial function relationship, calculating the formation pressure of the target gas storage in the peak peak of peak regulation and gas production in winter; 5, performing dynamic modeling by adopting a node analysis method, and calculating the productivity of different oil pipe sizes under different formation pressures and production pressure differences; and 6, by taking the productivity under the formation pressure in the peak period as a core basis and drawing a cross plot, quantifying and preferably selecting a reasonable oil pipe size according to the conditions that the productivity amplification is 10% and the critical sand production pressure difference is smaller than 3MPa. The blindness of oil pipe type selection is remarkably reduced, and the gas supply capacity and reliability of the gas storage in the peak regulation critical period are ensured.

The invention relates to a method for correcting physical property parameters of a multi-scale crack. The method comprises the following steps: measuring related parameters of the multi-scale crack, measuring opening degrees of cracks with different scales, measuring lengths of the cracks, analyzing a crack group system, and measuring sampling areas of samples with different scales. Preparing a rock sample, and calculating and correcting the crack opening; calculating fracture densities of different scales; the calculated fracture densities of different scales and the corrected fracture opening degrees of the corresponding scales are put into the cross plot, a multi-scale corrected fracture opening degree and fracture density relation chart is obtained, the relation between the multi-scale fracture densities and the corrected fracture opening degrees is established, and the multi-scale fracture development relation is established; multi-scale fracture density correction is carried out; and corrected multi-scale physical property parameters are calculated. Rock samples under different pressure conditions are selected, the fracture forming state is simulated, the multi-scale fracture development relation is established, the porosity and permeability of the corrected fractures of different scales are calculated, and more accurate data support can be provided for evaluation of contribution of the fractures to the reservoir.

A saturation correction method based on oil-water loss equivalent belongs to the technical field of petroleum and natural gas exploration and development and comprises the following steps: step 1, acquiring a core sample of a research area under the same conditions of pressure, temperature and coring process of a coring well section, and performing an oil-water saturation experiment on the core sample to obtain a core sample; obtaining the oil-water saturation of the experimental measurement rock core sample, and dotting the actually measured oil-water saturation value into the cross plot; and 2, correcting the actually measured oil-water saturation based on the oil-water loss equivalent of the research area to obtain an underground actual oil-water saturation value. Compared with the conventional method for correcting the oil saturation by singly utilizing a projection method, the method has the advantages that the oil saturation is corrected by considering the influence of different oil-water volatilization loss amounts, and the method is not limited to closed coring data and is simple to operate and good in correction effect.