35 results about "Rock density" patented technology

The invention discloses a method and a system for predicting the lumpiness of open-air throwing blasting, and relates to the technical field of rock blasting engineering. The invention discloses a new calculation relation about a lumpiness similarity proportion, relates to the technical field of open-air loose blasting mining, and can predict blasting lumpiness of projects such as mines, tunnels and the like by scaling a lumpiness distribution proportion. The method comprises the following steps: firstly, acquiring a rock sample from a blasting site, measuring parameters such as rock density and fracture toughness, and acquiring blasting parameter information of a to-be-blasted area; and then, a numerical simulation model under an open-air throwing blasting similar material is constructed by using a numerical simulation method, the change rule of blasting fragmentation lumpiness along with explosive unit consumption in a scale model test is studied, and the blasting lumpiness in a field blasting area is predicted according to the blasting lumpiness similarity ratio. According to the method, the change rule along with the unit consumption of the explosive is analyzed, the utilization rate of crushing energy of the explosive in surface blasting engineering is improved, reference is provided for blasting lumpiness control, and prediction of field blasting lumpiness before blasting is achieved.

The invention discloses a physical-data dual-drive bench blasting effect prediction method in the technical field of blasting construction and intelligent mining, which comprises the following steps of: dynamically calibrating a fractal dimension field, and constructing a rock blasting classification model by combining blasting indexes such as fractal gradient, rock density, uniaxial compressive strength and drilling speed; performing three-dimensional reconstruction on the geometric morphology of the step before blasting by using an unmanned aerial vehicle high-precision modeling technology, and importing a finite element simulation model to predict a key blasting effect; collecting an actual blasting effect after blasting, and correcting parameters of the numerical simulation prediction model; and constructing a data set of actual lumpiness distribution of the muck pile, establishing a mapping relation between the rock detonability grade and the charge density, and optimizing the differential time sequence and the single-hole charge amount. According to the invention, through fractal dimension field dynamic mapping and real-time feedback control, accurate adaptation of blasting energy and a rock mass structure is realized.

The invention relates to the technical field of oil and gas drilling, and discloses a rock density data processing method and system based on machine learning, a terminal and a medium. The photoelectric absorption index, the compensation density and an energy window parameter output through rock density logging are used as input parameters, the photoelectric absorption index and the compensation density of a nominal value are used as labels, a sample library is established, a learning model is established according to the sample library, and an artificial intelligence algorithm is used for processing energy spectrum data measured by the lithologic density logging instrument. The density and photoelectric absorption index evaluation accuracy and the lithologic density logging measurement precision are improved under the condition of complex well holes and stratums, and the exploration requirements of complex reservoirs such as unconventional reservoirs are effectively met.

The invention discloses a method for monitoring the relative gravity of surface subsidence in a coal mining process, and the method comprises the steps: arranging a quantum gravity base station at the periphery of a subsidence area, deploying a relative gravimeter in a basin according to a grid, arranging a fiber grating gravity sensing chain in an underground crossheading, and carrying a cold atom gravity gradiometer by adopting an unmanned plane for periodic scanning. A gravitational field-mass migration model is established based on real-time data, coal mining volume, rock stratum density change and earth surface gravity anomaly are associated, geological background interference is eliminated through wavelet multi-scale decomposition, and a gravity change value is optimized through hydrological correction in combination with water level and porosity. And when the corrected gravity change exceeds a threshold value, calculating a rock stratum fracture azimuth angle by using a gravity gradient tensor, inverting an equivalent mining thickness based on the gravity change, dynamically predicting a surface subsidence form in combination with a subsidence basin model, constructing a state vector in combination with gravity, gradient and deformation data, and realizing multi-source fusion prediction through a filtering algorithm.

The present application relates to the geological exploration technical field, more particularly, to a deep water super shallow layer natural gas reservoir rock physics shear wave velocity prediction method, comprising: calculating equivalent bulk modulus, shear modulus and density of a plurality of mineral mixed matrix according to shale content; then calculating skeleton bulk modulus and shear modulus; then calculating saturated rock bulk modulus and shear modulus through a model, and calculating saturated rock density through rock matrix density; distributing longitudinal and transverse velocities of suspended state and bearing state, and calculating equivalent longitudinal and transverse wave velocities; using equivalent longitudinal wave velocity to construct an inversion objective function with longitudinal wave velocity as a known condition; comparing actual longitudinal wave velocity with calculated longitudinal wave velocity; realizing nonlinear inversion of transverse wave velocity according to an algorithm, and obtaining transverse wave velocity of a to-be-inverted work area. The present application simultaneously considers rock physics models of particle suspended state and bearing state, and realizes transverse wave velocity prediction and deep water super shallow layer natural gas reservoir transverse wave velocity direct inversion.

The invention provides a modeling method and a saturation prediction method of a rock physical model containing non-uniformly distributed hydrate sediments. Comprising the steps of obtaining model parameters, calculating the porosity of a mineral skeleton based on the model parameters, calculating the bulk modulus and the shear modulus of a dry hydrate skeleton, calculating the bulk modulus and the shear modulus of a dry mineral skeleton, and calculating the bulk modulus and the shear modulus of a dry composite skeleton composed of the dry mineral skeleton and the dry hydrate skeleton. And calculating the rock bulk modulus and shear modulus when the fluid is saturated, calculating the rock density value when the fluid is saturated, and calculating the stratum longitudinal wave velocity and the stratum transverse wave velocity. According to the method, on the basis of the forming mechanism and distribution characteristics of the non-uniformly distributed hydrates, the non-uniformity of the hydrates and mineral particles is considered in the modeling process, the hydrates and the mineral particles are regarded as two independent rock frameworks, and the isotropic rock physical model suitable for the non-uniformly distributed hydrates is constructed.

The invention discloses a Young impedance and longitudinal and transverse wave velocity ratio nonlinear direct seismic inversion method based on an accurate YIRD-Zoeppritz equation. The Young impedance and longitudinal and transverse wave velocity ratio nonlinear direct seismic inversion method comprises the steps that the YIRD-Zoeppritz equation is obtained, and the Young impedance YI, the longitudinal and transverse wave velocity ratio PSR and the rock density are inversed through an ADA-MCMC-LpSC nonlinear inversion algorithm providing sparse prior information based on the Lp norm. Based on an accurate YIRD-Zoeppritz equation, the accurate prediction method for the Young impedance and the longitudinal and transverse wave velocity ratio under the ADA-MCMC-LpSC nonlinear optimization inversion algorithm is achieved, and the key geophysical problem that the accurate Zoeppritz equation cannot be directly used for predicting the Young impedance and the longitudinal and transverse wave velocity ratio parameters at the same time at present is solved.

The invention discloses a coal rock density calculation method, device and equipment. The method comprises the following steps: firstly, acquiring total rock mineral X diffraction experiment data, X-ray element data of target position coal rock, coal rock average porosity and coal rock average water saturation; obtaining the ash content mineral type of the coal rock according to the total rock mineral X diffraction experiment data; calculating the type of the ash mineral and the mass fraction of the organic matter mineral by utilizing the mass fraction of the characteristic element in the ash mineral and the X-ray element data; calculating the skeleton density of the coal rock by using the mineral density of the coal rock, the ash content mineral type and the mass fraction of the organic matter mineral; and calculating the density data of the coal rock at the target position by using the average porosity of the coal rock, the average water saturation of the coal rock and the skeleton density of the coal rock. In the process, after X-ray element data is obtained on a drilling site, a series of element calculation is carried out, the density data of the coal rock at the target position can be obtained, the calculation method is simple, and the requirement for timeliness while drilling is met.

The invention discloses a sensitization system for matching explosive density with rock density of an on-site mixed loading emulsion explosive truck. The sensitization system comprises a density data acquisition unit used for detecting the rock density rho r of a target area; the emulsion matrix conveying unit is used for conveying an emulsion matrix according to a preset flow Qm, forming a water film coated with a slow-release agent outside the emulsion matrix through a water ring, and conveying the water film to an emulsion matrix inlet of the static mixer through an independent pipeline; the sensitizer pump control unit is used for dynamically matching the sensitizer conveying flow QS according to the rock density rho r and the emulsion matrix conveying flow Qm, and conveying the sensitizer to the sensitizer inlet of the static mixer through an independent pipeline; the static mixer is used for controlling the shear rate so that the materials are only physically mixed. By means of the tail end mixing and dynamic control technology, the problems that in a traditional sensitization mode, the pressure fluctuation of an explosive conveying pipe is large, and the explosive density cannot be adjusted are solved, and meanwhile the explosive density can be adjusted in real time.

The application provides a method for calculating the density of a shale gas reservoir by using element logging, and the method comprises the following steps: according to the content of reservoir elements measured by element logging and the molecular formula of minerals in the reservoir, the mass fraction of each mineral and the density of rock framework are inversely calculated; according to the fitting curve of the content of nickel elements, the total organic carbon content in the reservoir is calculated; based on the minerals in the reservoir, the porosity of the shale gas reservoir is calculated; according to the content of illite, the water saturation and the gas saturation are calculated; and according to the calculation results, the rock density of the shale gas reservoir is calculated. The mineral component content and the rock framework density are inversely calculated by using element logging data, and then the total organic carbon content, the porosity and the water saturation and the gas saturation are sequentially calculated, so that the rock density of the reservoir is obtained, the calculation result error is small, the evaluation of the reservoir physical property is relatively accurate, and the theoretical and data support is provided for shale gas development; the method is simple in operation, reduces the difficulty of physical property parameter measurement, and is suitable for a wide range of applications.

The invention discloses a mechanical drilling speed prediction method based on CPLNet. The method comprises the steps that drilling parameters are collected and preprocessed; the drilling parameters comprise bit pressure, rotating speed, torque, well depth, natural gamma, resistivity, pumping pressure, displacement, rock density and drilling fluid density; extracting spatial features and time features of the preprocessed drilling parameters; performing channel dimension splicing on the spatial features and the time features to obtain combined features; performing fusion weighting on the combined features to obtain fusion features; and the mechanical drilling speed is predicted through a full-connection network based on the fusion features, and a drilling speed prediction value is obtained. According to the method, Peephole-LSTM and CBAM attention mechanisms are combined, feature association and long memory are captured, long-term dependence is overcome, and the drilling speed is accurately predicted.

The invention relates to the technical field of coal low-carbon mining, and discloses a sandy gravel geological underground diaphragm wall grooving precision intelligent control method and system.The method comprises the steps that a purified surrounding rock density change curve and a gravel enrichment area three-dimensional map are subjected to coal mine stratum fusion treatment, and a shaft surrounding rock stability coefficient is formed; combining the shaft surrounding rock stability coefficient with the real-time working parameters of the drilling machine, and outputting a coal mine stratum dynamic response index; the basic regulation and control parameters are subjected to coal mine construction multi-objective optimization calculation, and an optimal operation parameter combination suitable for a coal mine shaft is obtained; and generating a coal mine construction carbon efficiency index by the real-time carbon emission equivalent and the material carbon emission contribution value through specific weighted calculation of the coal mine. The system comprises a shaft surrounding rock data fusion analysis module, a coal mine grooving self-adaptive regulation and control module and a coal mine construction carbon effect monitoring module. The construction efficiency and green building requirements are both considered, and a complete technical solution is provided for underground diaphragm wall construction under the sandy gravel stratum condition.

The embodiment of the application relates to the technical field of seismic exploration, and discloses a brittle prediction method, device, equipment and medium for a rock reservoir, the prediction method comprising the following steps: based on well logging data of a target rock reservoir, a target layer section of the target rock reservoir is constructed according to rock components and rock physical characteristic parameters, so as to construct a rock physical model for representing the relationship between the volume modulus, shear modulus, rock density and the content of main brittle minerals of the rock; a model of a brittle indicator factor is constructed according to the rock physical model and the change of the content of the main brittle minerals, the brittle indicator factor being used for representing the relative brittle degree of the rock mass; and the brittle indicator factor is converted into actual brittleness for representing the actual brittle degree of the rock mass. The brittle prediction method disclosed by the application fully utilizes the rock physical characteristic analysis of the target rock reservoir to analyze the influence of the brittle minerals on the brittle prediction, and effectively improves the rationality and accuracy of the rock brittle prediction.

The invention relates to the technical field of safe blasting, in particular to a safe blasting method for a saturated zone deep rock stratum under a low-temperature condition, which comprises the following steps of: performing a rock mechanical property test on the saturated zone deep rock stratum under a low-temperature environment to obtain main mechanical parameters of rock density, wave velocity, porosity and Young modulus under different temperature conditions; based on test data, a dynamic constitutive model of the saturated zone low-temperature rock under the impact load effect is established, and the strain rate and the low-temperature effect are considered; according to the dynamic constitutive model, blasting parameters are optimized, and the blasting parameters comprise the explosive type, the explosive loading amount, the blast hole arrangement and the delay time; the method has the beneficial effects that the static and dynamic mechanical characteristics of the saturated zone low-temperature rock under different temperature and strain rate conditions are deeply revealed, the dynamic constitutive model is established, and a scientific basis is provided for cold region engineering design and blasting parameter optimization. An engineer can more accurately predict and control the rock breaking behavior in the blasting process, and the blasting efficiency and safety are improved.

This invention relates to the field of geological exploration and discloses a method for determining shale porosity using the difference in rock density and fluid mass. First, the apparent density is calculated by measuring the mass and apparent volume of a blocky rock sample. Then, the rock sample is crushed, extracted, and dried, the fluid mass loss is measured, and the skeleton density of the dried powder is measured. Finally, the volume difference per unit mass of rock is estimated using the reciprocal difference between the apparent density and the skeleton density, and then corrected for fluid loss mass to obtain the total porosity of the rock sample. This invention calculates porosity by using the density and fluid mass differences of rock samples with different particle sizes, and is not limited by the size of the rock sample or the fluid it contains. It can measure closed pores in the rock, and by using the fluid loss mass during crushing, washing / extraction, and drying processes for correction, a more accurate total shale porosity can be obtained.

The application discloses a rock characteristic stress identification method based on wave impedance characteristics, and comprises the following steps: S1, preparing a labeled rock sample; S2, collecting the longitudinal wave velocity under the uniaxial compressive strength condition; S3, calculating the rock density at each longitudinal wave velocity collection time; S4, calculating the rock wave impedance according to the data collected in S2 and S3; and S5, calculating the axial stress according to the axial load corresponding to each longitudinal wave velocity measurement time. The application provides a reliable and convenient quantitative identification method for the closed stress, cracking stress and damage stress of brittle rock. The method overcomes the limitations of the crack volume strain method, such as the solving precision and reliability, and the influence of the rock elastic modulus, Poisson's ratio value and natural fissure development degree.

The invention relates to an indoor evaluation method for well wall stabilizing capability of drilling fluid. The indoor evaluation method comprises the following steps: preparing a rock sample to carry out a drilling fluid and rock sample interaction experiment; determining a rock structure damage coefficient under the action of the drilling fluid through rock density and interval transit time tests; various mechanical experiments such as point load, compression resistance, tensile strength and fracture toughness are carried out, and the shale strength damage coefficient under the action of the drilling fluid is determined; based on rock strength weakening characteristics under the action of the drilling fluid, collapse pressure increment and fracture pressure decrement under the action of the drilling fluid are calculated, and a safety density window reduction coefficient under the action of the drilling fluid is obtained; the rock structure damage coefficient, the strength damage coefficient and the formation safety density window reduction coefficient are synthesized, the comprehensive coefficient of the drilling fluid well wall stabilizing capacity is calculated, and the larger the comprehensive coefficient is, the better the well wall stabilizing capacity is. The comprehensive influence of the drilling fluid on the rock structure, strength and safety density window is synthesized, and technical support is provided for guaranteeing the stability of the stratum well wall on site.

The invention relates to the technical field of oil sand detection, and discloses a target area oil sand resource quantity determination method, which comprises the following steps: collecting a plurality of oil sand samples of a plurality of areas of a target area, and determining the reservoir type of each area according to the average porosity and the average permeability of the oil sand sample of each area; performing single-hydrocarbon carbon isotope characteristic analysis on the oil sand sample of the region of the target reservoir type to determine an oil gas source of the region of the target reservoir type; performing inclusion uniform temperature and salinity test on the oil sand sample of the region of the target reservoir type to determine the oil gas formation period of the region of the target reservoir type; determining an oil sand storage area from the area of the target reservoir type according to the oil and gas source and the oil and gas formation period; and determining the oil sand resource quantity of the oil sand storage area according to the oil-containing area, the average effective thickness of the oil sand, the rock density and the corresponding acquisition coefficient of each depth domain in the oil sand storage area so as to improve the accuracy of estimating the oil sand resource quantity of the target area.

The invention relates to the technical field of oil exploitation and processing, in particular to a method and a device for acquiring the density of rock while drilling based on elements, electronic equipment and a storage medium, the acquisition method comprises the following steps: for a drilling well belonging to the same area as a drilled area, acquiring the A element content, the B element content and the C element content of a rock while drilling mineral sample of the drilling well, and inputting the A element content, the B element content and the C element content of the while-drilling rock mineral sample of the drilling well and the fitting parameters R1, R2 and R3 obtained by fitting into a nonlinear regression model, and calculating to obtain the while-drilling rock density of the while-drilling rock mineral sample of the drilling well. According to the nonlinear regression model established based on the elements, multiplicity of solutions is reduced, rock density acquisition is more efficient and accurate, and more reliable data support is provided for petroleum drilling operation.

The utility model relates to the technical field of geophysical exploration, concretely relates to a kind of auxiliary device for rock density determination, including two support frames, lifting mechanism for controlling rock sample lifting is installed between two support frames, weighing device is equipped between two support frames, container is placed on the weighing device, the container top surface is equipped with opening, the lifting mechanism is connected with the rock sample by pulling rope.The utility model can keep sample in stationary state during rock (ore) density determination process, avoid because of human external force instantaneous change to cause balance to be more difficult to tend stable and read, effectively reduce manpower cost, substantially improve determination efficiency.

Disclosed are methods, systems, and computer-readable medium to perform operations for calculating pore pressure in a reservoir, the operations including: receiving input data including: (i) a rock density in the reservoir, (ii) seismic data measured in the reservoir, and (iii) pore pressure measurement data from a Modular Formation Dynamic Tester (MDT); calculating, based on the rock density, an overburden pressure volume of the reservoir; generating, based on the overburden pressure volume, an overburden pressure volume of the reservoir; generating, based on the seismic data, an acoustic impedance volume of the reservoir; generating, based on the effective stress and overburden volumes, an estimated pore pressure volume of the reservoir; and calculating, based on the estimated pore pressure volume, a pore pressure gradient map indicative of the pore pressure in the reservoir.

The invention relates to the technical field of geological survey, and particularly discloses a rock resistivity measurement method considering water content change and application. The method comprises the following steps: firstly, synchronously acquiring initial mass and initial volume parameters of an on-site rock sample by using a weighing method and a drainage method, and further accurately calculating the initial density of the on-site rock sample; in the rock processing link, after the rock is processed into a regular geometrical shape, the rock volume is accurately measured, the theoretical mass is calculated by combining the initial density, meanwhile, the actual mass is obtained by adopting a weighing method, and the moisture content of the rock is accurately regulated and controlled by adopting a dehydration method or an infiltration method by comparing the difference between the theoretical mass and the actual mass. The deviation between the density of the processed rock and the initial density is controlled within an extremely small range, so that the initial physical state of the rock in the natural environment is effectively restored, and the measurement of the initial resistivity of the rock is realized. And the resistivity measurement result deviates from the true value of the natural state due to the significant change of the moisture content.

The utility model relates to the technical field of rock-soil permeability testing devices, and provides a rock-soil layer permeability testing device for land planning, which comprises a bottom box and a top box, the top box is arranged at the top of the bottom box, a connecting assembly is arranged between the bottom box and the top box, an extrusion detection assembly is arranged on the top box and the bottom box, and the extrusion detection assembly comprises an inner plate. High-density water holes are formed in the surface of the inner plate, a water injection pipe is arranged on the side surface of the top box, one end of the water injection pipe is connected with a sealing valve in a screwed mode, a drainage pipe is arranged at the bottom of the bottom box, an exhaust valve is installed on the drainage pipe, an inner threaded pipe is installed at the top of the top box, and a stud is connected into the inner threaded pipe in a screwed mode. According to the technical scheme, the problems of inaccurate measurement surface, uncertain density of rock at the periphery of the measurement hole and the like in the prior art are solved, and the problem that the reliability of detection data is reduced is solved.

The present invention provides a method for determining multi-component matrix porosity in shale and a method for evaluating oil and gas reservoirs. The method comprises: obtaining a matrix porosity value, rock density, and the mass percentages of each component; substituting the matrix porosity value, rock density, and mass percentages of each component of the shale sample into a preset first formula to obtain the unit mass pore volume of each component in the shale; and using a preset second formula to obtain the matrix porosity of each component in the shale. This method can calculate the multi-component matrix porosity, helping to understand the degree of shale pore development and its controlling factors, clarifying the size and proportion of the multi-component matrix porosity in the shale layer, and facilitating the calculation of rock reservoir space, fluid saturation, and geological reserves. The method is highly operational, computationally efficient, and accurate.

This invention discloses a method and apparatus for shale rock physical modeling. The method includes: determining a maturity index curve based on kerogen maturity correlation curves; determining the density, bulk modulus, and shear modulus curves of kerogen based on discrete data of kerogen modulus and the maturity index curve; determining the porosity curves of organic and inorganic matter based on the adsorbed gas and free gas content curves and the maturity index and density curves of kerogen; determining the dry rock density, P-wave and S-wave velocities, and shear modulus curves based on the density, bulk modulus, and shear modulus curves of kerogen, clay minerals, and other minerals, as well as the total porosity curve, and the porosity curves of organic and inorganic matter; and determining a shale rock physical model based on the dry rock density, P-wave and S-wave velocities, and shear modulus curves, and the bulk modulus and density curves of the mixed fluid. This method enables the reasonable establishment of a shale rock physical model based on the changes in organic matter during the maturation process.

The present application belongs to the field of tunnel and underground engineering geological survey and safe construction technology. A tunnel surrounding rock compressive strength evaluation method and system are proposed. The sound wave waveform travel time data and drilling process parameters in the tunnel advanced geological drilling construction process are obtained. The longitudinal wave velocity and transverse wave velocity are calculated based on the sound wave waveform travel time data, and then the dynamic elastic modulus, dynamic Poisson's ratio and rock integrity coefficient are calculated in combination with the rock density. The mechanical specific energy is calculated based on the drilling process parameters. With the drilling depth as the unified spatial coordinate axis, all the above parameters are aligned to the same depth point set to construct a multi-source fusion feature vector. The multi-source fusion feature vector is input into the preset surrounding rock compressive strength calculation model to obtain the continuous prediction profile of the surrounding rock compressive strength along the drilling depth. The present application realizes the rapid, continuous and high-precision evaluation of the tunnel surrounding rock compressive strength by fusing the multi-dimensional information of sound wave testing and drilling parameters, and provides a reliable basis for tunnel support design.

This invention discloses a method for monitoring the relative gravity of surface subsidence during coal mining. It involves deploying quantum gravity reference stations around the subsidence area, arranging relative gravimeters in a grid pattern within the basin, and arranging fiber optic gravity sensor chains in the underground roadway. Simultaneously, a UAV equipped with a cold atom gravity gradiometer performs periodic scans. Based on real-time data, a gravity field-mass migration model is established, correlating coal extraction volume, changes in rock density, and surface gravity anomalies. Wavelet multi-scale decomposition is used to eliminate geological background interference, and hydrological correction is applied, incorporating water level and porosity to optimize gravity variation values. When the corrected gravity variation exceeds a threshold, the azimuth of rock fracture is calculated using the gravity gradient tensor. Equivalent extraction thickness is derived based on gravity variation inversion, and the surface subsidence morphology is dynamically predicted using a subsidence basin model. A state vector is constructed by combining gravity, gradient, and deformation data, and multi-source fusion prediction is achieved through a filtering algorithm.

This invention discloses a method and system for predicting surface subsidence in goaf areas, belonging to the field of surface subsidence prediction technology. The method includes the following steps: collecting data on the uneven distribution of residual stress in the goaf area, constructing a three-dimensional seismic wave propagation scenario, and dividing energy-prone areas based on differences in rock density and elasticity; based on the spatial distribution data of these energy-prone areas, deploying graded stress release holes, and using a combination of directional pressure relief and deep grouting to form controllable stress buffer zones at energy-prone sensitive locations, thus establishing a stable residual stress background. This invention, by identifying energy-prone sensitive locations in the goaf in advance and constructing controllable stress buffer zones, transforms surface subsidence analysis from post-event analysis to pre-event perception. Furthermore, by combining dynamic stress and vibration time series to generate subsidence trend maps, it achieves forward identification and risk warning of secondary subsidence.

The invention discloses a rock density prediction method considering stratum shale content, and relates to the technical field of determination of stratum rock density through petroleum drilling and completion calculation, and the rock density prediction method comprises the following steps: S1, obtaining the shale content of a target stratum by using natural gamma of well logging information of drilled wells of the target stratum; s2, obtaining the rock density of the target stratum containing an undetermined coefficient by using the shale content of the target stratum and the logging longitudinal wave time difference; s3, correcting the rock density undetermined coefficient of the target stratum by using a least square method to obtain a rock density prediction method considering the shale content of the stratum; and S4, predicting the rock density of the target stratum by using a rock density prediction method. The stratum rock density is predicted only through the logging longitudinal wave time difference and the shale content, the density prediction precision is improved, meanwhile, the method has the advantages of being simple and easy to use, and the method can be used for calculating and determining the stratum rock density in the technical field of petroleum drilling and completion.

The application provides a carbon dioxide storage area safety geologic earthquake combined evaluation method, and the evaluation method comprises the following steps: S1, obtaining an isobath structure map based on three-dimensional seismic data and storage area drilling data; S2, obtaining a two-dimensional seismic profile according to the isobath structure map and interpreting the two-dimensional seismic profile as a two-dimensional geological profile; S3, obtaining overlying rock density ρ according to fault nearby well density logging data; S4, obtaining geological parameters according to the two-dimensional geological profile and calculating cross-section normal stress P; S5, obtaining fault zone argillan content S according to surrounding drilling data; S6, obtaining the formation pressure P1 of the target layer after gas injection according to the gas injection well; S7, obtaining a storage area safety index A according to the cross-section normal stress P and the formation pressure P1, and judging the safety of the storage area according to the safety index. The application provides an effective way for carbon dioxide storage area safety evaluation and provides a reference for carbon dioxide storage area oil and gas exploration and development.