107results about How to "Reduce exploration risk" patented technology

The invention discloses a determining method of complex mountain-front effective source rock and a source rock structural model. The method includes the steps of implementing spatial distribution of potential source rock, restoring erosion thickness of different structural unit formations, restoring features of a paleo-geothermal field, determining hydrocarbon conversion type of the source rock by numerical simulation, and determining distribution of the complex mountain-front effective source rock according to the spatial distribution features of the source rock, the hydrocarbon conversion types of the source rocks at different positions of the different structural units and features of abundance of organic matters. Meanwhile, by means of the study based on the method of recovering hydrocarbon conversion of the source rocks in the study area, reliability of resource quantity evaluation is improved, the blank in determining the complex mountain-front effective source rocks is filled, and results help greatly boost the progress of next resource evaluation.

The invention relates to a method and device for determining the oil and gas accumulation period of a complex superimposed basin. The method comprises the steps that a mode chart showing changes of the hydrocarbon generation potential index of a source rock along with the burial depth is made; the hydrocarbon expulsion threshold and the hydrocarbon expulsion rate of the source rock are determined according to the mode chart showing the changes of the hydrocarbon generation potential index of the source rock along with the burial depth; the hydrocarbon expulsion intensities are determined according to the hydrocarbon expulsion threshold and the hydrocarbon expulsion rate of the source rock; the hydrocarbon expulsion amounts are determined according to the hydrocarbon expulsion intensities; peak periods for discharging oil and gas are determined according to hydrocarbon expulsion amounts of different earth history periods; the planar hydrocarbon expulsion ranges of the source rock are determined according to the distribution areas and the hydrocarbon expulsion intensities of the source rocks at the different peak periods for discharging oil and gas; the oil and gas accumulation period is determined through superposition of the planar hydrocarbon expulsion ranges at the different peak periods for discharging oil and gas. The method and device solve the problem that the oil and gas accumulation period of a basin with oil and gas, especially of the complex superimposed basin, is difficult to determine, lower the risk of oil-gas exploration, indicate the oil-gas exploration direction, and have a wide application range.

The invention discloses an identification method and system for a complex basin edge super-stripped belt subtle trap boundary. The identification method includes the following steps that firstly, structural features of a plane of unconformity are analyzed and defined with data of earthquakes, well drilling, well measuring, well logging and the like as the basis; secondly, a geologic model is designed, forward modeling of earthquake responses is conducted, instantaneous phase earthquake attributes are extracted along the stratum, and a stratum super-stripped line for earthquake identification is depicted; thirdly, a geologic model capable of reflecting the super-stripped concept of the stratum is selected, earthquake forward modeling is conducted, and main factors affecting an error distance are defined; fourthly, an error distance formula under the stratum super-stripped condition is established; fifthly, the stratum subtle strap boundary is described according to the stratum super-stripped line and the error distance for the earthquake attribute identification. According to the identification method and system for the complex basin edge super-stripped belt subtle trap boundary, the position of the super-stripped line for earthquake identification can be accurately described, the subtle trap boundary is quantitatively identified based on an extrapolation formula built through multi-model forward modeling, an oil-gas accumulation boundary can be easily and accurately determined, and the oil exploration risk can be effectively lowered.

The invention discloses an earthquake high resolution processing method based on inversion of variable wavelet reflection coefficients. The processing method is a method for expanding frequency bands of earthquake records and is used for improving time resolution of the earthquake records. The processing method includes the steps of extracting shallow earthquake wavelets and wavelet time domain length according to the earthquake records, setting time windows and extracting an instant wavelet in each time window, establishing a variable wavelet convolution model of a frequency domain according to a wavelet convolution model of a time domain, for each earthquake record, setting model parameters for the instant wavelets and the variable wavelet convolution model and obtaining the reflection coefficients through inversion, and finally carrying out convolution processing on the initially extracted shallow earthquake wavelets and the reflection coefficients and obtaining the earthquake records with expanded frequency bands. The earthquake high resolution processing method expands the band frequency range of earthquakes, obviously improves the time resolution of the earthquakes, improves accuracy of seismic exploration work and provides a technical basis for accurate earthquake exploration and reducing risks of oil exploration.

The invention provides a method for determining a most favorable range of oil-gas reservoir distribution of a continental down-faulted basin. According to the method, at least one hydrocarbon potential index (S1+S2) / TOC is searched for a specific source rock area and statistic analyzing is carried out on the at least one hydrocarbon potential index (S1+S2) / TOC and a hydrocarbon expulsion threshold Z0 and a hydrocarbon expulsion rate qe are determined; a hydrocarbon expulsion strength Eq of the source rock is calculated; a distance parameter of entrapment to the center of the hydrocarbon expulsion strength and a distance parameter of entrapment to a hydrocarbon expulsion boundary are determined; and a most favorable range of petroleum distribution is determined by utilizing the determined distance parameters. According to the invention, a difficult problem of quantification of oil-gas distribution range prediction under the source control oil-gas effect can be solved and an important technical support is provided for the most favorable range prediction of oil-gas reservoir distribution and the current oil-gas exploration guiding can be provided.

The invention relates to a reservoir stratum prediction method. The method is characterized by through carrying out intersection analysis on logging data in a research area, determining effective parameters capable of distinguishing a reservoir stratum; comprehensively using earthquake data and the logging data to carry out forward simulation on the each acquired effective parameter respectively, correspondingly carrying out characteristic response analysis and determining an optimal parameter capable of distinguishing the reservoir stratum; carrying out reservoir stratum parameter inversion on the optimal parameter, determining a reasonable reservoir stratum prediction result according to an inversion result or comparing and analyzing a forward simulation result and the inversion result and then determining a reservoir stratum prediction result. By using the method, prediction precision is increased, exploration risks are reduced and workload is decreased. The method is an effective scheme of lithologic oil and gas reservoir stratum prediction.

The invention discloses a method of delineating a mineralization center based on a short-wave infrared spectrum. According to the method, in the interpreting process of the short-wave infrared spectrum, the influences of different deposit types, different landscapes and different surrounding rocks and source rocks on spectrum parameters are considered, qualitative description of the content of relevant altered minerals in a magmatic-hydrothermal metallogenic system is improved to quantitative interpretation, and the difficulties that accurate recognition is difficult and efficiency is low because rocks are not uniform and alteration is not representative in conventional petrographic identification are overcome. By deeply analyzing the influences of different influence factors on infrared spectrum information, the accuracy and mineral visibility at a delineated hydrothermal center can be greatly improved, the exploration risk is lowered, sample preparation is not needed, test time is short, energy conservation and environment protection are realized, the method is convenient and rapid to use, and the mineral exploration cycle is effectively shortened.

The method uses the relational model between the rock and the electricity to evaluate the saturation of the stratum fluid. In the method, I is a resistivity augmenting factor; R0 is a resistivity when the stratum contents 100% water, it unit is ohm.m; Rt is a stratum resistivity, its unit is ohm.m; SW is a water saturation of stratum; Phi is porosity; Vsh is shale content; U is wettability index; Y is parameter; C is constant.

The invention relates to a method for directly generating angle gather by using wave-equation migration, which is applied to seismic data processing in seismic exploration and is a method for forming the wave-equation pre-stack depth migration of the angle gather of seismic migration. The method directly utilizes shot-domain migration results for generating the angle gather imaged by an underground reflecting interface by calculating the incident angle of a seismic source outgoing wave at an underground imaging point, and compensates the change of the nonuniform coverage of an observing system for amplitude. The angle gather directly corresponds to the parameter changes of physical properties of target layers and provides accurate angular-domain seismic reflecting strength for pre-stack inversion. The method has the core that because the incident angle of a seismic source wave field is determined by directly using a single-route wave algorithm, the method is better matched with a wave-equation migration method while avoiding the instability of a ray method. Compared with migration calculation, because only the simple-harmonic wave field of the single-route wave is utilized for the calculation of the incident angle, the metering amount in the method can be ignored. The method can be applied to two-dimensional and three-dimensional wave-equation pre-stack depth migration treatment and has an important application value in the explorations of oil gas resources and mineral resources.

The invention discloses a method for determining air / water relation by using a compact sandstone microscopic aperture structure. The method comprises the following steps: according to pore throat median radius, porosity and permeability of a compact sandstone sample on each storage layer of a sampling well, establishing a calculating model of pore throat median radius, porosity and permeability; according to the porosity and permeability of the compact sandstone sample on each storage layer of the sampling well by the calculating model, calculating the pore throat median radius of the compact sandstone sample on each storage layer of the adjacent well, according to power condition and porosity change of a compact sandstone gas reservoir with different depth or reservoir dynamic evolution, establishing a change model of a storage state of compact sandstone air / water on each storage layer; according to the change model and the pore throat median radius, predicting the air water distribution characteristic and output state of compact sandstone on each storage layer. The above technical scheme can predict air water distribution characteristic and output state of compact sandstone, so that oil gas drilling success rate can be increased.

The invention relates to a method for compiling a paleogeologic map of carbonate rock strata based on the sequence stratigraphy, which comprises the steps of performing division calibration on sequence strata on the basis of basic data information, building carbonate connected well profile sequence stratigraphic framework and spatial sequence stratigraphic framework, analyzing the mutual superimposition relation of different strata on the profile and spatial development characteristics and distribution rules, specifying the mode and sequence structure of rhythmic strata of carbonate rocks, anddelimiting the structural boundary and range; taking a stratum thickness map as a base map, drawing stratum boundaries corresponding to different sequence stratigraphic interfaces according to the stratigraphic superimposition relation from old to new; and then correcting the stratigraphic boundaries according to the special geological phenomenon interpreted by the existing data, supplementing map elements and thus completing the drawing of the paleogeologic map. The method not only can ensure the accuracy of geological information, but also can guide the actual exploration and development more effectively, thus reducing the risk of exploration and development, and reducing the cost input of th exploration and development.

The invention provides a simulation experiment method and device for corrosion of a high temperature and high pressure reservoir. The simulation experiment method includes: determining rock mineral composition and element contents of a reservoir sample; determining a corrosion reaction solution according to the fluid characteristics experienced during reservoir geological evolution; determining the temperature and the pressure of corrosion reaction in a simulation experiment according to formation temperature and pressure experienced during reservoir burial evolution; determining the corrosionmode of the simulation experiment according to the corrosion mode during reservoir burial evolution; and carrying out the corrosion simulation experiment to complete the simulation of the corrosion of the high temperature and high pressure reservoir. The present invention also provides the simulation experimental device that can be used in the method. The simulation experimental method and devicecan realistically simulate reservoir conditions.

The invention relates to a predication method of the outer-source entrapment fullness degree. The method comprises the steps that nine geological factors of entrapment depth, a sand body inclination angle, sand body volume, fault sealing performance, distance between entrapment and an oil source fault, cover layer thickness, cover layer quality, cover layer mobility and residual pressure which are relevant to the outer-source entrapment fullness degree are selected; entrapment with the same oil deposit type under the same structural setting is selected, the nine factors and the computed fullness degree of the entrapment are obtained respectively, scatter diagrams are drawn respectively, and the relation of a single factor and the entrapment fullness degree is obtained through a fitting function; through multiple linear regression, a predication model of the entrapment fullness degree is established for the single factor relation; and model testing and correction are carried out. The predication model is high in pertinence, under the same structural setting, identical oil deposit type entrapment predication accuracy is high, the technical problem that outer-source entrapment fullness degree predication is hard is solved, the unknown outer-source entrapment fullness degree can be predicted in a quantitative mode, and significance is achieved in guiding of oil gas exploration and deployment.

The invention provides a method and device for determining oil-gas possibility of a carbonate rock buried hill. The method comprises the steps of calculating a phase index according to rock core measured data and logging data; calculating a potential index; calculating a phase and potential coupling index according to the phase index and the potential index, and calculating a source control index; calculating a phase and potential source control oil-gas effect index according to the phase and potential coupling index and the source control index; and determining the oil-gas possibility of the carbonate rock buried hill according to the buried hill single well productivity and the phase and potential source control oil-gas effect index. According to the method and the device, the technical problem that the oil-gas possibility of the carbonate rock buried hill cannot be accurately judged in the prior art is solved, the technical effect of accurately judging the oil-gas possibility of the carbonate rock buried hill is achieved, exploration risks are reduced, and the oil-gas drilling success rate is improved.

The invention provides a method for measuring the accumulation probability of an oil-gas anticlinal reservoir. The method comprises the following steps that: four major function factors for controlling the formation and the distribution of the oil-gas anticlinal reservoir, including hydrocarbon source rocks (S), palaeohighs (M), phases (D) and regional cap rocks (C) are determined; through analyzing the oil-gas control features of each function factor, a single-function factor reservoir control geological model is built; the single-function factor reservoir control probability is determined through the geological model; through the superposition of all of the function factors in the same accumulation period, the single-period accumulation probability of the oil-gas anticlinal reservoir is determined; and through the superposition of the single-period accumulation probability of the oil-gas anticlinal reservoir in different accumulation periods, the accumulation probability of the oil-gas anticlinal reservoir is determined. The method provided by the invention has the advantages that the problem of quantitative evaluation in the existing oil-gas exploration is solved; the risk of the oil-gas exploration is greatly reduced; and the success rate of the oil-gas drilling exploration is improved.

The present invention provides a foreland basin alluvial fan fine description and prediction method. The method comprises a step of establishing a foreland basin alluvial fan geological model, a step of establishing the stratigraphic framework of an alluvial fan, a step of carrying out seismic facies and attribute inversion to delineate the plane distribution range of an alluvial fan, a step of carrying out three-dimensional electrical inversion to divide the phase band boundary of the alluvial fan of each period, carry out the fine identification of internal lithology and lithofacies, and determine the spatial distribution characteristics of the lithology and lithofacies, and a step of applying OpenDtect software to analyze the alluvial fan vertical evolution and establishing the deposition model of a study area alluvial fan. The method provided by the invention is mainly based on the sedimentology theory and the geological model foundation established by alluvial fan exposure investigation, logging, seismic, electrical method and other materials are fully utilized, the means of logging geological interpretation, seismic sequence analysis, seismic facies interpretation, attribute analysis and electrical method interpretation are integrated, and each phase band of the alluvial fan and the internal lithology and lithofacies spatial distribution characteristic are effectively identified.

The invention relates to a non-destructive detection method based on the micro power spectrum density and an application thereof. The detection method comprises the steps of 1, data acquisition; 2, preprocessing and processing analysis for original acquisition data; 3, result map drawing; 4, analysis and interpretation. The application of the micro power spectrum density based detection method isthat the detection method is used for detecting longitudinal and transverse inhomogeneous geologic bodies within a depth range of 100m at the shallow earth's surface in urban engineering construction.The advantages lie in that a non-destructive detection method is provided for longitudinal and transverse inhomogeneous geologic bodies of the shallow earth's surface in urban engineering construction, and the detection method has the advantages of convenient field collection, high detection precision, high resolving power and abilities of shortening the investigation period, reducing the engineering cost and reducing the exploration risk and the like.

The invention relates to a Q structure establishment technology based on a prestack seismic channel set earth layer. The technology comprises the following steps: starting from a prestack seismic channel set, and estimating a Q value of the earth layer by a time-frequency spectral decomposition technology; extracting the prestack seismic channel set; performing relative amplitude preserved processing on the seismic channel set; performing time-frequency conversion on a target reflecting layer segment in the seismic channel set; obtaining the Q value of the earth layer which changes with the offset distance by an improved spectra ratio method based on the prestack seismic channel set in a time-frequency domain; and obtaining the Q value of the earth layer with zero-offset distance by return-to-zero processing. The prestack seismic data has better results and richer information than the post-stack seismic data, so the Q structure establishment technology helps reduce exploration risk and obtain more accurate results.

The invention discloses a method and device for determining lithologic oil-gas reservoir forming probability. The method comprises the following steps of determining the oil-gas reservoir forming probability of a lithologic oil-gas reservoir inside a target area under the control of a source rock single factor; determining the oil-gas reservoir forming probability under the control of a single factor of a low potential area; determining the oil-gas reservoir forming probability under the control of a single factor of sedimentary facies; determining the oil-gas reservoir forming probability under the control of a single factor of a regional cap rock; determining the lithologic oil-gas reservoir forming probability according to the oil-gas reservoir forming probabilities under the control of the single factors of the source rock, the low potential area, the sedimentary facies and the regional cap rock, wherein according to the step of determining the oil-gas reservoir forming probability under the control of the single factor of the low potential area, interface potential indexes of the low potential area are determined according to the maximum interface potential, the minimum interface potential, the maximum porosity and the minimum porosity of the low potential area, and then the oil-gas reservoir forming probability under the control of the low potential area is determined. According to the technical scheme, the reservoir forming probability of the lithologic oil-gas reservoir is quantitatively predicted, and the exploration direction of the lithologic oil-gas reservoir is indicated.

The invention discloses a method for identifying a non-bright spot oil reservoir in a third AVO bright spot characteristic reservoir stratum zone, and belongs to the technical field of oil exploration and development. In the method, seismic data and well data are comprehensive utilized, wave impedance models of different reservoir stratum numbers are established for forward simulation, the corresponding relationship between the reservoir stratum wave impedance model and the non-bright spot oil reservoir is determined, a forward data body of the non-bright spot oil reservoir is generated on the basis of the corresponding relationship, inversion parameters which are sensitive to the non-bright spot reservoir stratum are preferably selected out by means of a constraint sparse spike inversion algorithm, wave impedance inversion is applied to actual seismic data, and a reasonable seismic reservoir stratum prediction result is finally determined. According to the invention, forward and inversion combined prediction of the reservoir stratum is carried out, the prediction precision is improved, the exploration risk is reduced, and the method for identifying the non-bright spot oil reservoir is an effective means for predicting a lithologic oil reservoir stratum.

The invention provides a method and a device used for determining critical exhaust strength of tight sandstone gas reservoir exhaust source rocks. The method comprises steps that, stratum data of a target interval of a tight sandstone gas reservoir research zone is acquired, stratum hydrostatic pressure, gas water interface tension force under the stratum condition, natural gas compression factors and capillary force are determined according to the acquired stratum data, gas bulging force under the force balance condition is calculated, and the critical exhaust strength is calculated according to the stratum temperature, effective hydrocarbon source rock thickness, hydrocarbon source rock porosity and natural gas substance amount of the acquired stratum data, and the natural gas compression factors and natural gas density acquired through calculation. The method solves a technical problem of difficulty in quantitatively predicting the critical exhaust strength of the tight sandstone gas reservoir exhaust source rocks in an oil gas basin in the prior art, improves exploration efficiency of tight sandstone gas and reduces risks in exploring tight sandstone gas reservoirs.

The invention discloses a reflection coefficient inversion reservoir prediction method based on a weighted stacking noise suppression strategy. The method includes six main steps: 1), through a noise disturbance analysis, determining a source of noise influencing the inversion effect, and distinguishing seismic noise and inversion noise; 2) performing seismic noise suppression preprocessing on seismic data through a post-stack wavelet frequency division method; 3) for de-noised seismic data, constructing reflection coefficient inversion key parameters (a wavelet inverse transform factor F, an inversion predominant frequency band Q, and an inversion initial model S(n)); 4) suppressing inversion noise through weighted stacking of inversion results of multiple regularization parameters to obtain reflection coefficient inversion results; 5) performing quality control (QC) on the inversion results through spectrum analysis and a calibrated sound wave curve to obtain final result data; and 6) performing sand body fine interpretation based on the reflection coefficient result data, and predicting sand body spatial distribution characteristics. Compared with other thin reservoir prediction methods, according to the reflection coefficient inversion reservoir prediction method, the inversion anti-noise performance is high, thin-layer interference in the original seismic data can be eliminated, the prediction precision of the thin layer is greatly improved, and oil and gas exploration risks are reduced.

The invention provides a method and equipment for measuring pore structures and fluid characteristics of strata. The method includes selecting multiple stratum samples; analyzing the multiple stratum samples to determine a rock-electricity relationship model; determining stratum water saturation according to the rock-electricity relationship model; determining stratum oil-gas saturation according to the stratum water saturation; determining stratum water resistivity according to the rock-electricity relationship model; collecting logging information of current reservoirs; comprehensively interpreting the logging information according to the stratum water saturation, the stratum oil-gas saturation and the stratum water resistivity, and acquiring the stratum water saturation, the stratum oil-gas saturation and the stratum water resistivity of the current reservoirs. By the method and the equipment, influences of non-Alchie phenomena can be reflected, stratum oil-gas content can be accurately evaluated through the novel rock-electricity relationship model, accuracy of reservoir oil-gas evaluation can be effectively improved, and oil-gas exploration risks can be lowered.

The invention provides a method for quantitatively evaluating the degree of enrichment of contactor-relay control natural gas reservoirs, and belongs to the technical field of gas field exploration. The method comprises the following steps: selecting six geological factors related to the degree of enrichment of the contactor-relay control gas reservoirs: average gas generating strength in a source rock-fault contact point, source rock-fault contact area, reservoir formation period source-stored residual pressure difference, natural gas longitudinal migration distance, fault dip cosine value, and a preservation condition parameter; selecting a plurality of proven gas reservoirs, obtaining corresponding six factors and a enrichment degree parameter of the proven gas reservoirs, drawing a scatter diagram, and obtaining a relation between a single factor and the degree of enrichment; establishing a multi-factor prediction model of the degree of enrichment of contactor-relay control natural gas reservoirs by treating the relation with multiple linear regression; and primarily selecting an exploration potential region, obtaining corresponding six factors of the exploration potential region, and selecting an exploration potential region according to the multi-factor prediction model. As a multi-factor comprehensive prediction model is established, the quantitative evaluation precision of the degree of enrichment of the contactor-relay control gas reservoirs can be improved effectively.

The invention discloses a seismic elastic impedance low-frequency information extraction method and system, and a storage medium. The method comprises the following steps: obtaining seismic data and actually measured elastic impedance data; inverting elastic impedance data through a neural network according to the seismic data; forward modeling seismic data are generated according to the elastic impedance data, and a seismic data loss value is obtained; obtaining a loss value of the elastic impedance according to the elastic impedance data and the actually measured elastic impedance data; obtaining a minimum total loss value and a low-frequency curve according to the seismic data loss value and the loss value of the elastic impedance; performing seismic inversion and reservoir prediction based on the minimum total loss value and the low-frequency curve; according to the scheme, the neural network method is introduced for seismic low-frequency information extraction, the extracted low-frequency characteristics are good, the calculation efficiency is high, the reservoir prediction precision can be remarkably improved, the exploration risk is reduced, and the method can be widely applied to the technical field of geophysical exploration.

The invention provides a method and an apparatus for quantitatively predicting a reservoir forming probability of a fault block oil-gas reservoir. The method comprises the steps of determining main control factors of fault block oil-gas reservoir formation and distribution, wherein the main control factors include a hydrocarbon source kitchen, a phase, a fault zone and a regional cap formation, and the regional cap formation, the phase, the fault zone and the hydrocarbon source kitchen are arranged from top to bottom longitudinally; according to oil-gas control characteristics of the hydrocarbon source kitchen, building an oil-gas control geological model of the hydrocarbon source kitchen, and determining a reservoir forming probability of the fault block oil-gas reservoir under the control of the single factor, namely, the hydrocarbon source kitchen; according to oil-gas control characteristics of the phase, building an oil-gas control geological model of the phase, and determining areservoir forming probability of the fault block oil-gas reservoir under the control of the single factor, namely, the phase; according to oil-gas control characteristics of the fault zone, building an oil-gas control geological model of the fault zone, and determining a reservoir forming probability of the fault block oil-gas reservoir under the control of the single factor, namely, the fault zone; according to oil-gas control characteristics of the regional cap formation, building an oil-gas control geological model of the regional cap formation, and determining a reservoir forming probability of the fault block oil-gas reservoir under the control of the single factor, namely, the regional cap formation; and determining the reservoir forming probability of the fault block oil-gas reservoir.

The invention belongs to the technical field of uranium and thorium mineral product prediction and evaluation, and particularly relates to a method for predicting pegmatite type uranium and thorium resources related to alkaline magma, which comprises the following steps: step (1), carrying out geological survey, and clarifying mineral control element characteristics; (2) carrying out surface energy spectrum measurement, and evaluating a surface mineralization distribution range; (3) soil radon gas measurement is carried out, and the deep mineralization abnormal range is evaluated; step (4), carrying out audio magnetotelluric profile measurement, and delineating an ore control structure range; and (5) multi-information superposition is carried out, and the deep uranium and thorium ore body is predicted and evaluated. According to the method, exploration is carried out on the basis of analysis of multivariate information such as geological ore control elements, the concealed ore body can be predicted more accurately, effectively and quickly, the prospecting efficiency is improved, and the exploration cost is reduced.

The invention discloses a method and device for depth domain velocity modeling in a desert area. The method comprises the following steps that a shallow superficial depth domain velocity model is established; a middle and deep depth domain velocity model is established; velocity fusion of the shallow superficial depth domain velocity model and the middle and deep depth domain velocity model is conducted to obtain a shallow, middle and deep integrated depth domain initial velocity model; and the shallow, middle and deep integrated depth domain initial velocity model is updated iteratively by using an isotropic tomography velocity inversion technology and anisotropy tomography velocity inversion technology. According to the method for depth domain velocity modeling in the desert area, a high-precision depth domain velocity model of the desert area can be obtained, and imaging quality of high-depth migration can be further improved.

The invention relates to a comprehensive optimization evaluation method of an oil and gas drilling target. The method comprises the steps that 1 basic geological condition analysis is carried out to calculate the oil and gas area and resource amount; 2 geologic risk quantitative evaluation is carried out to calculate the geological risk factor; 3 the minimum economic reserve scale plate is established through classification; 4 a risk-economic evaluation plate is established and a grading standard is established; and 5 the comprehensive optimization evaluation of the oil and gas drilling target is carried out. According to the comprehensive optimization evaluation method of the oil and gas drilling target, limited resources can be reasonably allocated; the exploration risk is reduced; and the credibility of exploration investment decision-making is greatly enhanced.

The invention provides a method and device for predicting the hydrocarbon saturation of a reservoir, and the method comprises the following steps: obtaining the physical information of a rock matrix of the reservoir; determining a frequency-varying zero offset seismic amplitude attribute and a frequency-varying attenuation attribute according to the reservoir rock matrix physical information; according to the frequency-varying zero offset seismic amplitude attribute and the frequency-varying attenuation attribute, determining the saturation distribution characteristics of the subsection hydrocarbon; and determining the hydrocarbon saturation predicted by the reservoir according to the segmented hydrocarbon saturation distribution characteristics, the frequency-varying zero offset seismic amplitude attribute and the frequency-varying attenuation attribute. According to the method, the final reservoir hydrocarbon saturation distribution rule is obtained by integrating the prediction results of the frequency-varying zero offset seismic amplitude attribute and the frequency-varying attenuation attribute, the prediction precision of the reservoir hydrocarbon saturation under different geological background conditions is improved through segmented frequency constraint prediction, and the exploration risk is reduced.