147 results about "Clastic rock" patented technology

The present invention belongs to the technical field of geological exploration deep Earth. The system of the present invention is configured to: collect seismic data, and preprocess original seismic data to obtain standardized gamma ray logging parameters; extract features from the standardized gamma ray logging parameters to obtain a variance attribute curve while drilling; obtaining a formation thickness prediction model of each set based on the variance attribute curve while drilling; acquire frequency-division seismic data based on the standardized seismic data by means of a frequency-division processing method based on wavelet transform; acquire optimal seismic frequency band information based on a predicted formation thickness value of each set; establish a geological prediction model of the current formation based on the frequency-division seismic data, the optimal seismic frequency band information, historical gamma ray logging parameters and the standardized gamma ray logging parameters.

The invention provides a deep complex volcaniclastic rock identification method based on a neural network. The method comprises the following steps: extracting feature data; performing label coding and data normalization processing on the logging data sample; establishing a deep complex volcaniclastic rock recognition model based on the neural network; and optimizing the deep complex volcaniclastic rock recognition model of the neural network. According to the deep complex volcaniclastic rock identification method based on the neural network, a Dropout mechanism of a multi-dimensional activation function and a hierarchical prediction method are introduced into the BP neural network model, and an over-fitting phenomenon is avoided by reducing the complexity of the neural network model and refining a step-by-step prediction standard; a new prediction model is established for deep complex volcaniclastic rock reservoir lithology identification, and the lithology identification method and system which are more accurate, objective, high in feasibility and credibility and lower in economic cost are obtained.

The invention discloses a comprehensive source discrimination method suitable for a complex clastic rock system, and relates to the technical field of petroleum and natural gas exploration and development. According to the method, the space imaging advantage of three-dimensional seismic data of a research work area on an underground geologic body is fully utilized, and the material source of a complex clastic rock system is comprehensively judged by recognizing the carrying process of sedimentary substances and combining the datum plane cycle, logging facies and rock facies achievements. According to the method, the carrying process of the sediment can be more effectively highlighted, and interpretation personnel can be helped to more effectively clarify a material source system. The method disclosed by the invention is suitable for comprehensive distinguishing research on the material sources of the complex clastic rock system, and is expected to be applied to lithofacies paleogeography recovery and mineral resource development of a multi-material-source system basin.

The invention relates to the technical field of geophysical logging, in particular to an XGBoost algorithm-based clastic rock reservoir granularity median inversion lithology identification method, which comprises the following steps of S1, constructing a granularity median M-logging multivariable data set; s2, dividing the granularity median M in the data set into a plurality of granularity types; s3, establishing a granularity type identification model, and then judging the granularity type to which the unknown depth point on the shaft section belongs; and S4, establishing a granularity median logging intelligent calculation model based on an XGBoost algorithm under granularity classification, then calculating a continuous granularity median curve, and then identifying the lithology of the clastic rock reservoir according to the corresponding relationship between the lithology and the granularity median. According to the method, granularity analysis and conventional logging information are fully mined, geological significance is combined, the granularity samples are classified, then the calculation model of the granularity median is established through the XGBoost algorithm, low-cost and high-precision granularity median continuous calculation can be achieved, and therefore low-cost and high-precision identification of the lithology of the clastic rock reservoir is achieved.

The invention is suitable for the field of oil and gas field exploration and development, and discloses a clastic rock hydrogen-rich reservoir logging identification method, system, equipment and medium, and the method comprises the steps: identifying an oil and gas reservoir in a clastic rock reservoir according to the difference of conductivity of fluid of the clastic rock reservoir; identifying a gas reservoir in the clastic rock reservoir according to the difference of the influence of oil and gas in the oil and gas reservoir on the elastic modulus of the stratum; and recognizing the hydrogen-rich reservoir according to the gas density difference in the gas reservoir and the difference of the gas occurrence environment. According to the technical scheme, the hydrogen-rich reservoir in the clastic rock reservoir is identified by comprehensively utilizing well logging methods such as depth and depth resistivity well logging, density well logging, neutron well logging, acoustic well logging and natural gamma-ray spectrum well logging, and the effectiveness and accuracy of hydrogen-rich reservoir identification are improved.

The present application relates to the technical field of oil and gas exploration. Disclosed are a clastic rock reservoir porosity prediction method, and an apparatus. The method comprises: acquiring temperature evolution data and pressure evolution data of a layer to be predicted; according to the temperature evolution data, establishing a first function model of the temperature of said layer evolving over the burial time; according to the pressure evolution data, establishing a second function model of the pressure of said layer evolving over the burial time; according to the first function model, determining a time-temperature index; according to the second function model, determining a time-pressure index, the time-pressure index reflecting the rule of fluid overpressure changing over time; inputting the time-temperature index, the time-pressure index and an original porosity before burial of said layer into a pre-established prediction model, so as to output a current porosity of said layer, the prediction model reflecting the association relationship between the time-temperature index, the time-pressure index, the original porosity and the current porosity. The present application can improve the precision of porosity prediction for clastic rock reservoirs.

The invention provides a method and a device for determining spatio-temporal evolution of clastic rock diagenetic fluid in a fractured basin. The method for determining spatio-temporal evolution of clastic rock diagenetic fluid in the fractured basin comprises the following steps: acquiring authigenic minerals at different structural positions of the fractured basin; wherein the authigenic minerals comprise carbonate, quartz secondary enlargement and anhydrite; determining the paleofluid temperature of the authigenic mineral according to the uniform temperature of the saline inclusion of the authigenic mineral and the uniform temperature of the hydrocarbon inclusion; and determining the spatio-temporal evolution process of the clastic rock diagenetic fluid of the broken basin according to the paleo-fluid temperature, the predetermined burying history of the broken basin and the paleo-ground temperature gradient. According to the method, the activity time range of diagenesis fluid in clastic rock reservoirs at different structural positions is determined, so that fluid difference evolution modes of different structural positions of the broken lake basin are established, and technical support is finally provided for predicting causes of high-quality clastic rock reservoirs.

The invention relates to the technical field of petroleum and natural gas exploration and development, and discloses a relative isochronous logging and earthquake calibration method, which is characterized in that a multi-well average velocity unified calibration method is adopted for calibration of the top and the bottom of a marker bed, and trend correction is carried out on a velocity body according to errors and layer space distribution characteristics; and finally, the calibration error of the above-well layering and the seismic interpretation layer is very small, and the result is in normal distribution. In the calibration process, the single well curve is not stretched or compressed, it is guaranteed that the speed trend is reasonable, no distortion section exists, and the speed model is closer to the real speed. The method mainly aims at calibration of thin sand layers which are thin in thickness, rapid in transverse change and unstable in distribution in continental clastic rock deposition in China, and particularly has a good effect on connectivity research such as development area small layer comparison and water injection.

According to the horizontal well guiding method based on multidisciplinary interaction verification, successful implementation of the horizontal well can be effectively ensured according to complex geological characteristics such as heterogeneity of clastic rock reservoirs and transverse changes of gas layers. In the target entering stage of the horizontal well, important adjusting nodes and reasonable well inclination angles are determined, multiple vertical positioning methods are applied, step-by-step accurate control over different node positions is achieved, and accurate target entering of the horizontal well is guided and achieved. In a horizontal section implementation stage, horizontal well drilling is guided by using a horizontal section guided sedimentary model, a three-dimensional earthquake model and a three-dimensional geologic model, so that earthquake targeted macroscopic prediction and fine regulation and control of the geologic model are realized.

The invention belongs to the technical field of exploration and development of fault block oil and gas reservoirs, and particularly relates to a seismic prediction method and system for igneous rock intrusive fault zone sealing performance, and the method comprises the steps: determining the seismic attribute and seismic frequency attribute of a highlight body of a target interval according to petroleum seismic exploration data; determining magma invasion characteristic parameters according to the seismic attribute and the seismic frequency attribute of the highlight body, and determining fracture characteristic parameters of the fracture zone according to an eigenvalue characteristic algorithm operation result in the third-generation coherent attribute of the seismic data; determining an internal structure index of the intrusive fault zone according to the magma invasion characteristic parameters and the fracture characteristic parameters of the fault zone; and comparing the internal structure index of the intrusive fault zone with a closed lower limit threshold of the internal structure index of the known oil reservoir fault zone, and predicting the fault zone closure and the closure capability thereof according to a comparison result, thereby realizing quantitative determination of the oil and gas migration and dredging capability of the fault with magma invasion in the clastic rock stratum.

The invention discloses a marine clastic rock reservoir modeling method based on geological cause information, which relates to the technical field of geological modeling, and comprises the steps of collecting and preprocessing modeling data, obtaining preprocessed data, performing geological background research on a target area, performing profile analysis and interface identification on the preprocessed data, and obtaining a marine clastic rock reservoir model. Extracting and converting inclination angle information from the preprocessed data, identifying and quantifying interlayer features, generating a probability distribution constraint body, performing sequential indication modeling, and verifying, optimizing and applying the model; according to the method, multi-source data is integrated to deeply research the sea entering and sea exiting rule, an interface is accurately identified, a sedimentary facies belt is divided, a foundation is laid for reservoir analysis, dip angle information is innovatively utilized, the dip angle information is converted into a probability value and fused into sequential indication modeling, interlayer distribution is accurately simulated in combination with reservoir characteristics and a variation function, and the reservoir analysis result is obtained. And the characterization capability of the model on a complex reservoir structure is obviously improved.

The invention provides a method, a system, equipment and a medium for determining the granularity median of clastic rock, and the method comprises the following steps: building a granularity median histogram based on the experimental analysis result of the granularity of the clastic rock; based on the granularity median histogram, establishing a thermodynamic diagram of the debris granularity median data and multiple groups of logging data, and determining a logging curve of density, natural gamma and neutron-density porosity difference with relatively high correlation with the granularity median; performing Z-value standardization on the logging curves of the density, the natural gamma and the neutron-density porosity difference with relatively high correlation with the particle size median; extracting standardized logging curve characteristics by adopting a principal component analysis method, and calculating a comprehensive evaluation value F by selecting a principal component variable of which the cumulative variance contribution is greater than a preset value; according to the obtained comprehensive evaluation value F, fitting by using a multiple linear regression method to obtain a particle size median of the clastic rock; the purpose of accurately calculating the particle size median of the clastic rock can be achieved, and reliable parameters are provided for geological exploration.

The invention belongs to the technical field of oilfield development, and discloses an oil and gas reservoir modeling processing system based on clastic rocks and a use method of the oil and gas reservoir modeling processing system. The data processing system is used for processing fault and logging data, geological stratification data and well perforation data, the grid management system is used for dividing and encrypting grid types, the model building system is used for building a digital-analog model and an oil-gas reservoir relation model, and the digital-analog management system is used for outputting the built model. And the established digital model is convenient to modify and reconstruct, so that the digital model pretreatment work requirement of complex oil and gas reservoir types is met, the historical fitting speed of subsequently realizing numerical simulation is improved, and the modeling treatment of clastic rock oil and gas reservoirs is facilitated.

A chlorite coating coverage rate calculation method relates to the technical field of geological exploration and comprises the following steps: collecting a typical rock core sample of a clastic rock stratum in a research area, observing sedimentary characteristics, judging sedimentary microfacies, testing physical properties of the rock core sample and chlorite content data, and preparing a sample slice for high-precision observation. Identifying and shooting the particles with chlorite coatings, calculating the coating coverage rates of the sample sheet particles by adopting a cross proportion method, a perimeter proportion method and an angle proportion method respectively, and then taking the mean value of the coating coverage rates of the three methods as the total coating coverage rate of the sample particles; carrying out linear coupling on the calculated total coating coverage rate of the sample particles and the chlorite content, and establishing a relationship between the chlorite coating coverage rate and the chlorite content; according to the method, under the condition that comprehensive actual geological conditions of the clastic rock reservoir containing the chlorite coating are fully considered, the content calculation method of the chlorite coating in the clastic rock reservoir is emphatically solved, and the coverage degree of the chlorite coating can be accurately judged.

The application provides a clastic rock reservoir seismic sequence high-resolution division method and system, S1 obtains the sensitive well logging curve of the well closest to the seismic trace, adopts a cumulative prediction error method to process the sensitive well logging curve to obtain a cumulative prediction error curve, and performs generalized S transformation on the sensitive well logging curve to obtain time-frequency distribution characteristics; S2 performs long-term and short-term cyclic sequence interface identification by using the cumulative prediction error curve and the time-frequency distribution characteristics to obtain long-term and short-term cyclic sequence interfaces; S3 calibrates the long-term and short-term cyclic sequence interfaces to the well seismic trace, performs well seismic trace seismic sequence division, adopts an atomic matching tracking technology to perform well-seismic time-frequency matching analysis in the time-frequency domain, identifies seismic implicit sequence interfaces, and obtains a clastic rock reservoir high-resolution seismic sequence framework after all seismic traces are calculated. The application obtains a high-resolution seismic sequence framework, and provides strong support for improving the precision and accuracy of clastic rock reservoir prediction.

The invention discloses a method for determining a black shale material source carrying path, and relates to the technical field of shale oil and shale gas exploration and development engineering. According to the method, the contents of clay minerals and feldspar are specially selected to be combined with the granularity of shale particles to establish a series of plane contour maps, and through superposition of the plane contour maps, a carrying path with siliceous clastic rock as a main material source, a carrying path with carbonate rock as a main material source and a carrying path of gravity flow are judged; and the carrying path of the black shale of the target layer series in the research area is determined through superposition of the carrying paths. According to the method for determining the carrying path of the black shale material source, the ancient landform of the sedimentary basin can be effectively recovered, an important means is provided for optimization of a favorable shale oil and gas exploration and development area, and then the success rate of well drilling can be effectively increased.

The invention provides a method for improving prediction precision of a deep clastic rock thin reservoir and application of the method, and relates to the technical field of oil exploration and development. The method comprises the following steps of: aiming at a deep clastic rock reservoir section, constructing guided filtering processing on three-dimensional seismic data; then carrying out spectral bluing frequency expansion processing to obtain a processed three-dimensional seismic data volume; carrying out correction and logging rock physical parameter intersection analysis on the logging curve; constructing an isochronous stratigraphic framework model, and using the 90-degree phase rotation three-dimensional seismic data volume to carry out waveform indication inversion; line drawing is carried out on the top and bottom interfaces of the predicted reservoir, interlayer attributes are extracted, and the boundary of the reservoir is depicted finely; and performing time-depth conversion by using the top-bottom interface of the predicted reservoir after line drawing, subtracting the top depth from the bottom depth, and generating a reservoir plane equal-thickness map by using a difference value, thereby realizing plane distribution and feature fine prediction of the complex clastic rock thin reservoir. The matching degree of the prediction result and the actual drilling well is high, and technical support is provided for efficient exploration and development of deep clastic rock oil and gas reservoirs.

The invention relates to the technical field of oil-gas exploration, in particular to a clastic rock buried hill stratum comparison and division method. A clastic rock buried hill stratum comparison and division method comprises the following steps that S1, the structure background of a buried hill in a target area is known, and single-well rock stratum analysis is carried out with stratigraphy as guidance; s2, on the basis of collected single well, well connection and seismic datum plane recognition, cycle analysis of lithology, rock electricity and seismic response is carried out, and well connection and seismic stratigraphic comparison is carried out; s3, in combination with the comparison result of the lithology combination, the rock electricity combination and the seismic response characteristics, the difference of the drilling reveal strata series characteristics between different areas is determined, and a sedimentary reference plane with obvious characteristics and typical phenomena is found according to the comparison result; s4, step-by-step comparison is carried out on the target horizon according to the development characteristics of the strata series between the regions, the preservation condition of each strata series is determined, well-connected rock stratigraphic comparison and division are completed, and a stratigraphic framework is established.

The invention relates to a clastic rock reservoir porosity evolution recovery method under a tectonic extrusion background, and belongs to the technical field of petroleum and natural gas exploration and development. The method comprises the following steps: calculating the total compaction pore reduction amount of clastic rock samples, selecting samples with similar burial depths, similar rock structures and different maximum paleotectonic stresses as selected samples, and calculating the total compaction pore reduction amount of the clastic rock samples according to the difference value of the total compaction pore reduction amount corresponding to two selected samples with adjacent maximum paleotectonic stresses. Obtaining the lateral compaction pore reduction amount of the maximum palaeotectonic stress, and establishing a function relationship between the lateral compaction pore reduction amount and the maximum palaeotectonic stress; the lateral compaction hole reduction amount of each time of lateral extrusion in the multiple lateral extrusion processes is calculated; according to the total compaction hole reduction amount and the lateral compaction hole reduction amount, the vertical compaction hole reduction amount is calculated, and a relation chart of the vertical compaction hole reduction amount and the buried depth is established; and drawing a geological historical period porosity evolution curve of the clastic rock reservoir under the tectonic extrusion background by utilizing an inversion back-stripping method and combining the lateral compaction pore reduction amount and the vertical compaction pore reduction amount. The method solves the problem that the lateral and vertical compaction hole reduction amount cannot be quantitatively calculated in the evolution recovery process of the porosity of the foreland basin reservoir.

The invention provides a sedimentary subfacies and microfacies quantitative identification method, and the method comprises the steps: S1, constructing a sedimentary subfacies and sedimentary microfacies database, and determining a sea or lake plane evolution process; s2, establishing a sedimentary concept model, and extracting a data set of virtual well lithology, sedimentary subfacies and sedimentary microfacies; s3, carrying out logging curve forward modeling simulation on the lithology of the virtual well; s4, establishing a discrimination model based on a support vector machine supervision algorithm; s5, verifying the accuracy of the discrimination model; and S6, carrying out sedimentary subfacies and sedimentary microfacies combined judgment on a to-be-evaluated well by utilizing the judgment model to obtain a sedimentary subfacies and sedimentary microfacies judgment result. Batch, efficient and accurate identification of sedimentary subfacies and microfacies of multiple types of clastic rocks can be carried out, the method has important application value for prediction of clastic rock reservoir distribution rules and remaining oil, and meanwhile, favorable technical support is provided for construction of intelligent oil fields and geological large databases.

The invention relates to a clastic rock while-drilling granularity evaluation method based on element logging parameters. The problem of clastic rock reservoir granularity while-drilling analysis is solved by utilizing the element logging parameters. K, Na, Ti, Mn, Ni, Fe and Zr are preferably selected as sensitive parameters for indicating the particle size of the reservoir, a calculation method for the particle size index of the sunken clastic rock reservoir in the West Lake during well logging while drilling is established, and meanwhile, the particle size grading standard of the sunken clastic rock reservoir in the West Lake is established. According to the method, classification while drilling and quantitative evaluation of clastic rock granularity can be rapidly realized, and the method has the advantages of accuracy, rapidness, convenience and low cost.

The invention discloses a clastic rock sedimentary bedding type rapid identification method and system, and the method comprises the steps: carrying out the high-resolution scanning of a rock core column image through scanning equipment, obtaining a collection image, sequentially carrying out the image preprocessing and meshing of the collection image, and obtaining a sample image; carrying out edge detection on the sample image to obtain a sample texture layer line, and carrying out skeletonization processing on the sample texture layer line to obtain a sample texture layer curve set; according to the method, the functions of extracting the morphological parameters of the sample sedimentary stratification of the high-resolution rock core scanning image by adopting an image processing technology and quantifying the similarity between the sample sedimentary stratification and the standard sedimentary stratification by utilizing a mathematical algorithm to accurately recognize the type of the sedimentary stratification are realized, so that the recognition efficiency of the sedimentary stratification of the clastic rock is improved; and the identification accuracy of the clastic rock sedimentary stratification is guaranteed, the working efficiency of field investigation and indoor rock core description of geological workers is improved, and the method is suitable for being widely popularized and used.

The invention belongs to the technical field of deep clastic rock resource exploration, and particularly relates to a method for judging the lower limit of pre-stored pore permeability of scale corrosion occurrence of a deep clastic rock reservoir. According to the method, by comparing the pore permeability, corrosion surface porosity and mineral component differences before and after an acid injection displacement experiment of compact clastic rocks and clastic rocks containing stress fracture nets, the development capability of corrosion pores is represented, and whether a communicated pore channel allowing an acid fluid to be in contact with soluble minerals needs a certain pre-stored pore permeability condition or not is verified. And on the basis, carrying out an acid injection displacement experiment on a clastic rock sample to be detected, and comparing the porosity and permeability difference, the porosity difference of the corrosion surface and the mineral component difference before and after so as to characterize the development capability of the corrosion hole and judge the pre-stored porosity and permeability lower limit condition of the development of the scale corrosion hole of the deep reservoir. And when the clastic rock has the pre-stored pore permeability lower limit condition, determining that the deep clastic rock is a deep high-quality reservoir.

The present application relates to a rock porosity calculation method and system based on clastic rock thin section identification data, and belongs to the technical field of oil and gas exploration and geology engineering. The method comprises the following steps: obtaining a first compaction rate according to the carbonate content data in the current clastic rock thin section identification data and the fitting relationship between the carbonate content and the compaction rate in the historical data; obtaining a second compaction rate according to the clay contribution rate obtained from the current clastic rock thin section identification data and the fitting relationship between the clay contribution rate and the compaction rate obtained from the historical data; obtaining a comprehensive compaction rate by weighted average of the first and second compaction rates; obtaining a modified compaction rate by modifying the comprehensive compaction rate according to the ratio of clay to initial porosity and the ratio of carbonate to initial porosity; determining the calculated porosity by using the modified compaction rate; and obtaining the rock porosity by modifying the calculated porosity according to the dissolution and cementation of the thin section. The clay contribution rate is the ratio of the square root of the clay content to the sum of the clay content and the carbonate content.

The invention discloses a logging curve adaptive clustering ultrafine lithology classification method for enhancing carbonate rock-clastic rock transition type lithology identification, and relates to the technical field of lithology classification. The method comprises the steps that after logging data are loaded, missing values are processed firstly, and samples with the non-null-value proportion larger than or equal to 80% are reserved; preprocessing the well logging data after completion; screening the geologic features, and removing geologic redundant information; the global structure and local lithology details of the sedimentary system are reserved through UMAP self-adaptive dimensionality reduction; hDBSCAN clustering parameters are determined in a self-adaptive mode based on the sedimentary body scale and the lithologic continuity, and quantitative evaluation and early warning are carried out on the clustering quality; and finally, based on traditional color matching of sedimentary geology, lithology-color geological mapping is established, and lithology distribution of sequence cycle is visually reflected. The method can meet the high-precision lithology classification requirements of complex stratums (such as heterogeneity, curve missing and multiple transition type lithology).

A method for correcting physical properties of laumontite-rich clastic rock reservoirs based on overburden pressure porosity and permeability tests includes: conducting porosity and permeability tests on rock samples under normal temperature and pressure conditions; analyzing a type of a reservoir cement and characteristics of a reservoir space; comparing variations in the porosity and permeability between a laumontite-containing reservoir and a laumontite-free reservoir under overburden pressure conditions; fitting a variation function to establish relations between porosity, permeability, and overburden pressure in the laumontite-containing reservoir; and creating a correction plate of the permeability of the reservoirs with different laumontite contents.

A method for identifying a tensile-shear fracture in a strong-tectonic extrusion zone clastic rock and related device, comprising: collecting geological data of a well drilling a target layer at a turning end position of an extrusion anticline in a same tectonic belt; determining a homogenized fracture opening degree in a single lithologic layer and a difference between a horizontal maximum principal stress and a vertical stress of the single lithologic layer based on the geological data, drawing an intersection graph, and determining a potential position of tensile-shear fracture development on the intersection graph; verifying the potential position of tensile-shear fracture development on the intersection graph through a tensile-shear fracture identified on a single well core; and determining an identification standard of the tensile-shear fracture based on the verification. The present application calculates in-situ ground stress and the difference between the horizontal maximum principal stress and the vertical stress by using logging data, and identifies the tensile-shear fracture of a well section lacking coring data in a strong-tectonic extrusion zone based on core data verification and the relationship between the normalized fracture opening degree and the corresponding ground stress difference, thereby providing a basis for the prediction and evaluation of the tensile-shear fracture in a similar area.

The invention discloses a clastic rock reservoir porosity prediction method and device, and relates to the technical field of petroleum and natural gas exploration, and the method comprises the steps: obtaining temperature evolution data and pressure evolution data of a to-be-predicted layer; according to the temperature evolution data, establishing a first function model of the temperature of the to-be-predicted layer evolved along with the burying time; according to the pressure evolution data, establishing a second function model of the pressure of the to-be-predicted layer evolved along with the burying time; determining a time temperature index TTI according to the first function model; determining a time pressure index according to the second function model; the time pressure index reflects the rule that the fluid overpressure changes along with time; the TTI, the time pressure index and the original porosity before burying of the to-be-predicted layer are input into a pre-established prediction model, the current porosity of the to-be-predicted layer is output, and the prediction model reflects the incidence relation among the TTI, the time pressure index, the original porosity and the current porosity. According to the method, the prediction precision of the porosity of the clastic rock reservoir can be improved.

A method for calculating a dynamic T2 cutoff value of a deep clastic rock reservoir comprises the steps that firstly, a rock sample nuclear magnetic resonance experiment is carried out on a certain deep clastic rock reservoir, and the T2 cutoff value is determined; secondly, calculating a difference quotient value of saturation porosity components of the nuclear magnetic resonance experiment of the rock sample, and reading a second T2 value intersected with the relaxation time axis from left to right; thirdly, establishing a conversion relational expression between a T2 cutoff value determined by a rock sample nuclear magnetic resonance experiment and a T2 value calculated by difference quotient; and finally, performing difference quotient processing on the T2 value of the actual nuclear magnetic resonance logging to obtain a second T2 value intersected with the relaxation time axis, and substituting the T2 value into a conversion relation between the constructed experimental T2 cutoff value and the difference quotient calculation T2 value, so that the dynamic T2 cutoff value of the deep clastic rock reservoir can be calculated point by point. According to the method, the defects of a method for calculating the variable T2 cut-off value of the deep clastic rock reservoir in nuclear magnetic resonance logging are overcome, and technical support is provided for accurate evaluation of the movable fluid of the reservoir and accurate calculation of the permeability in nuclear magnetic resonance logging.

The present application relates to a kind of methods for restoring porosity evolution of clastic reservoirs under tectonic extrusion, belonging to the technical field of oil and gas exploration and development.The method comprises the following steps: calculating the total compaction and pore loss of clastic rock samples, selecting samples with similar burial depth, similar rock structure and different maximum paleo-tectonic stress as selected samples, obtaining the lateral compaction and pore loss of the one with larger maximum paleo-tectonic stress by the difference of total compaction and pore loss corresponding to the two selected samples adjacent to the maximum paleo-tectonic stress, and establishing the functional relationship between lateral compaction and pore loss and maximum paleo-tectonic stress;calculating the lateral compaction and pore loss of each lateral extrusion in multiple lateral extrusions;calculating the vertical compaction and pore loss according to the total compaction and pore loss and lateral compaction and pore loss, and establishing the relationship chart between vertical compaction and pore loss and burial depth;using the inverse back stripping method, combining lateral compaction and pore loss and vertical compaction and pore loss, and drawing the porosity evolution curve of clastic reservoirs in geological history under tectonic extrusion.This method solves the problem of being unable to quantitatively calculate lateral and vertical compaction and pore loss in the process of restoring porosity evolution of foreland basin reservoirs.