38 results about "Overburden pressure" patented technology

The present application belongs to the technical field of geotechnical engineering and indoor test, and provides a visual test device and method for interaction between high-pressure rotary jet flow and soft soil, which comprises a detachable model box, a jet medium simulation system, a high-pressure rotary jet flow generation system, an overburden pressure simulation system, a data acquisition system and a tracing system.The test device has the advantages of high visual degree, detachability, easy assembly and easy production.The jet medium simulation system has significant shear thinning characteristics, and has a high degree of reduction of the non-Newtonian fluid properties of cement slurry, which not only overcomes the problem of easy blockage of the pipeline, but also avoids distortion defects.The trajectory of the fluorescent powder particles in the jet medium simulation system can be captured by a high-speed camera under the irradiation of the pulsating laser beam generated by the pulsating laser, so as to accurately reproduce the flow field information of the high-pressure rotary jet flow in the soft soil.

The application provides a calculation method of pore pressure of a tectonic compression formation. The calculation method of pore pressure of the tectonic compression formation comprises the following steps: S1, obtaining a density trend curve, and performing integral calculation on the density trend curve to obtain overburden pressure S V ; S2, determining total porosity POR of the formation based on acoustic logging, density logging, neutron logging or nuclear magnetic resonance logging; S3, analyzing characteristics of a target layer section to determine a tectonic compression coefficient ACm_C of the formation; S4, solving a pore pressure coefficient PP of a mudstone section based on a pore pressure model corrected based on the tectonic compression coefficient ACm_C; S5, determining a relationship between effective stress P eff and biot coefficient α and total porosity POR; and S6, inversely deducing a pore pressure coefficient of a reservoir section according to the relationship between the effective stress P eff and the total porosity POR. The application solves the problem of low calculation accuracy of the pore pressure calculation method in the prior art.

An experimental device for reconstruction and production increase of natural gas hydrate reservoirs includes a simulation test kettle, and a high-pressure sand filling system, a fracture-forming loading system, an overburden pressure loading system, a gas pressurization system, a fracturing system and a data collection system which are respectively connected with the simulation test kettle. A reservoir medium is arranged in the simulation test kettle, the generation of fractures with various fracture widths and / or fracture shapes is simulated in the simulation reaction kettle by the fracture-forming loading system, the reservoir medium is compacted by the high-pressure sand filling system, seabed overburden pressure is simulated for the reservoir medium by the overburden pressure loading system, gas is pressurized and then enters the simulation test kettle, a fracturing fluid or proppant is injected into the simulation reaction kettle by the fracturing system, and experimental data is collected and obtained.

The invention relates to the technical field of deep dynamic disaster control, and discloses an overlying strata low-position pressure relief and high-position filling dynamic disaster coupling control design method which comprises the following steps: dividing strata units of a research area; and a low-position pressure relief model is established, and crustal stress balance calculation is carried out. And deep hole blasting schemes with different blasting parameters are designed, and circulating excavation and balance calculation are conducted on the coal seam till coal seam excavation is completed. Monitoring points are arranged on the overlying strata of the low-position pressure relief model, and a dynamic change curve of rock mass stress and displacement is obtained. And meanwhile, position coordinates of upper and lower rock stratum boundaries of the separation space are screened, and a grouting material unit conforming to the separation space form is generated. Proportional segmentation is carried out according to a grouting area, and different grouting filling rates are set; and designing a grouting material unit, and creating a high-position filling model. And comparing numerical results of different low-position pressure relief models and high-position filling models, carrying out coupling design on the two numerical models, and designing an optimal dynamic disaster coupling control scheme.

The application provides a method for calculating the ground stress based on the whole process formation leak-off test of a directional well, comprising the following steps: performing the whole process formation leak-off test on the target directional well and recording the test data; calculating the horizontal minimum ground stress and the overburden pressure according to the test data of the whole process formation leak-off test and the rock mechanics characteristic parameters of the target directional well; calculating the fracture pressure value under all possible arrangement combinations of the horizontal maximum ground stress and the horizontal minimum ground stress at the well deviation azimuth of the target directional well according to the stress distribution around the well section of the formation leak-off test well and the tensile failure criterion; drawing the contour map of the fracture pressure to establish the ground stress query chart of the target directional well; and querying the horizontal maximum ground stress corresponding to the calculated horizontal minimum ground stress in the ground stress query chart. The application calculates the ground stress based on the test data of the whole process formation leak-off test of the target directional well, and effectively improves the accuracy of the calculation result of the ground stress size.

To provide an ejecta suppression and ground subsidence suppression system of liquefaction ground which confirms that a crushed shell drain composed of a crushed shell suppresses reduction in drainage performance accompanied by mixing of sand compared to a gravel drain, and is effective as a liquefaction countermeasure drain, and in which since the crushed shell is small in dry density and is extremely lightweight compared to a crushed stone, the dead weight in a ground improvement area is small, and the system has an effect for further reducing a ground subsidence amount after liquefaction.SOLUTION: An ejecta suppression and ground subsidence suppression system, ejecta being from an improvement ground surface by earthquake time liquefaction in an improved ground where a crushed shell drain is laid, includes: selecting a crushed shell having such a coefficient of permeability that a seepage pressure by an excess pore water pressure difference of the crushed shell drain laid on the ground is not higher than an effective placement pressure of the crushed shell drain, after liquefaction; laying the crushed shell drain formed of the selected crushed shell; and improving the ground.SELECTED DRAWING: Figure 1

This invention discloses a method and system for intelligently determining critical pressure based on multi-level matching data, comprising the following steps: data acquisition and preprocessing; executing a hierarchical matching strategy according to a preset priority order to select relevant overburden pressure porosity and permeability experimental data points for the target reservoir from a core physical experimental database; pressure-permeability curve fitting; critical pressure determination; and outputting the critical pressure value and related analysis results. This invention significantly improves the efficiency, accuracy, and automation level of critical pressure assessment based on overburden pressure porosity and permeability experimental data, reduces excessive reliance on new, high-cost, long-cycle overburden pressure experiments, and provides more reliable and timely technical support for refined pressure management, reservoir protection strategy formulation, production enhancement measure optimization, and core analysis experimental pressure threshold calculation during oil and gas field development.

The invention discloses a gas storage well productivity calculation method in a complex seepage environment, and the method comprises the steps: carrying out a rock core stress sensitivity experiment under multi-cycle injection and production: carrying out the multi-cycle injection and production rock core experiment, and building a stress sensitivity quantitative characterization model considering the effective covering pressure and the cycle round influence; implementing a high-speed injection-production non-darcy flow experiment: carrying out high-speed non-darcy flow experiment on cores with different permeability and porosity, and establishing a quantitative characterization model of a non-darcy flow coefficient; and construction of a gas storage capacity equation: based on the stress sensitivity quantitative characterization model and the quantitative characterization model of the non-darcy flow coefficient, forming the gas storage injection-production capacity equation through seepage field simplification and conformal transformation modeling, simultaneous operation of a gas motion equation and a state equation and construction of an unsteady seepage differential equation. According to the method, the functions of accurately predicting the productivity of the vertical well and the horizontal well of the gas storage and effectively evaluating the injection-production capacity under the multi-period injection-production condition are achieved.

This application discloses a device and method for monitoring the direct burial stability of heating pipelines, which can effectively monitor and provide early warning of the direct burial stability of heating pipelines in real time. The device includes a pipeline installation kit, with one kit installed at each monitoring point of the heating pipeline. Each kit is equipped with a pressure sensor, an inclination sensor, a UWB tag, and a power supply module. The pressure sensor acquires the overburden pressure data at the monitoring point, and the inclination sensor acquires the pipeline inclination data. The UWB tag generates and transmits a UWB signal based on the overburden pressure and inclination data. A UWB base station receives the UWB signals transmitted by adjacent UWB tags, timestamps the UWB signals, and uploads the UWB signals and their timestamps to a cloud platform. The cloud platform is used to analyze and determine the direct burial stability of the heating pipeline based on the data uploaded from multiple UWB base stations.

The present application belongs to the field of oil and gas exploration, and particularly relates to a device and method for determining gas-measured porosity under overburden pressure. The device for determining gas-measured porosity under overburden pressure comprises: a core holder for accommodating a rock sample, a pressure boosting device connected to the core holder to apply overburden pressure to the rock sample, a space-adjustable gas chamber with an internal space volume capable of being adjusted, the space-adjustable gas chamber being connected to the core holder, and a gas measurement system connected to the core holder and the space-adjustable gas chamber to pass in gas with a preset pressure, thereby measuring the porosity of the rock sample. In the present application, during the calibration of the pore volume, the continuous change of the internal space of the space-adjustable gas chamber is used to obtain a pore volume-pressure standard curve with multiple measuring points through a single gas expansion process, thereby avoiding the purpose of calibrating the pore volume by repeatedly loading and unloading the sample in the core holder, and greatly simplifying the steps of calibrating the pore volume.

The present application relates to the technical field of oil reservoir fracture attribute description, and particularly relates to a fracture attribute fusion method based on fractured low-permeability oil reservoirs. The method comprises the following steps: establishing a fracture intensity model by combining well data with seismic data, establishing a fracture network model according to the fracture intensity model, obtaining a natural fracture attribute volume, fitting to obtain shear wave time difference data, first establishing a density model, a longitudinal wave model and a shear wave model, then establishing a rock mechanics parameter model, establishing an overburden pressure and pore pressure model according to the overburden pressure and the pore pressure of the overlying strata of a single well, establishing a ground stress model and simulating and calculating artificial fracture attribute data according to the rock mechanics parameter model and the overburden pressure and pore pressure model; fusing the artificial fracture attribute data to the natural fracture attribute volume, obtaining a fused fracture attribute volume and establishing a target geological model, and simulating and calculating fracturing artificial fracture parameters. The method provided by the present application fuses the fracture attributes of natural fractures and artificial fractures, and improves the description accuracy of fracture attributes.

The invention discloses an experimental method and device for simulating physical property changes of a gas storage under alternating working conditions. The method comprises the following steps: carrying out a first nuclear magnetic resonance test on a rock sample subjected to saturated water treatment to obtain a T2 spectrum of the rock sample and corresponding pore throat distribution; carrying out a triaxial mechanical experiment on the rock sample, and simulating the stress environment change under the alternating working condition of different operating years; carrying out a stress sensitive experiment on the rock sample after the triaxial mechanical experiment is carried out each time, calculating the overburden pressure permeability of the rock sample under a preset net stress test point, and obtaining a stress sensitive curve; and carrying out a second nuclear magnetic resonance test on the rock sample after the last round of stress sensitive experiment to obtain a T2 spectrum of the rock sample after the stress sensitive experiment and corresponding pore throat distribution. According to the method, stress sensitivity testing of the gas storage in different operation periods is achieved by setting different simulation years, and powerful technical support is provided for scientifically determining the effective gas storage space and the gas injection and production capacity of the gas storage well and achieving good economic benefits.

The application discloses a regionalized method for improving top coal caving rate based on well up and down combined operation, which comprises the following steps: step one, constructing an accurate three-dimensional geological model of the target coal seam roof; step two, constructing a horizontal directional long borehole along the minimum horizontal principal stress direction of the coal seam roof; step three, performing directional sand blasting and tight cutting in the horizontal directional long borehole; step four, performing fracturing construction on the horizontal directional long borehole by well up and down combination; step five, performing directional sand blasting and tight cutting and fracturing construction on all the horizontal directional long boreholes; and step six, mining the bottom coal, and the reformed top coal naturally falls under the overburden pressure, thereby improving the top coal caving rate. The application can inject high-pressure water into the target top coal through the horizontal directional long borehole of the coal seam roof, when the water pressure reaches the coal rock mass cracking pressure, cracks are generated in the coal seam roof and the top coal and are extended, the integrity of the top coal is damaged, and the purposes of weakening the coal rock mass and improving the top coal caving rate are achieved.

The present application belongs to the technical field of oil and gas production, and relates to a core processing method for simulating a formation fracture network for reservoir damage and protection evaluation, comprising the following steps: preparing a plurality of core columns reflecting the formation composition of the evaluation oil and gas reservoir; taking the prepared core columns, forming forces in the directions of two horizontal principal stresses and overburden pressure on the core columns according to a preset loading mode and interval time, so that the same fracture-microfracture fracture network as the formation rock of the oil and gas reservoir is formed in the core; obtaining a stereogram of the fracture network through digital core scanning, and calculating the fracture degree and high-density mineral data of the fracture body, and establishing the fracture distribution of the core after fracturing, until the fracture degree and high-density mineral data of the core column are consistent with the fracture degree and high-density mineral data of the formation core. The present application can produce a formation rock core consistent with the formation seepage channel, and the established core better simulates the formation condition, and the evaluation result is more reliable.

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 provides a thin vein foam concrete layered filling method, and relates to the technical field of mining engineering.The thin vein foam concrete layered filling method comprises the steps that a three-dimensional model is constructed by scanning a thin vein area, and the layer height of layered mining is determined according to the ore body thickness, the dip angle and the equipment operation height; after layer-by-layer mining is conducted from the bottom layer, a goaf layer is scanned, and the minimum design strength is calculated on the basis of the overlying stratum pressure and the roof span height ratio; a plurality of matching combinations are generated within the matching range of cement, water, a foaming agent and tailings, the strength is not lower than the design strength as the constraint, the strength is predicted in combination with a deep learning model, and the optimal matching is selected through multi-objective optimization of the unit mass material cost, the strength and the slump; finally, foam concrete filling slurry is prepared according to the optimal proportion and injected into a mining layer, and safe, economical and efficient layered filling mining from bottom to top is achieved.

The invention provides a rock core saturation correction method and device, and the method comprises the steps: firstly, converting the saturation of a rock core on the ground into the saturation of a corresponding stratum according to the overburden pressure pore permeability experimental data of the rock core and the fluid high-pressure physical property experimental data; then, the reservoirs are classified according to the absolute permeability of the rock core, and a diversion rate expression under the reservoir of the current category is determined according to oil-water relative permeability experimental data; according to the diversion rate expression, the saturation of the corresponding stratum is subjected to multi-process inversion to recover the loss amount, so that a saturation correction model is generated; wherein the saturation correction model is used for representing the saturation after loss recovery; and finally, solving the saturation correction model by taking the sum of the oil saturation and the water saturation after loss recovery as 1 as an objective function so as to correct the saturation of the rock core. According to the method, the rock core analysis saturation value can be reasonably corrected, so that the rock core analysis saturation value can directly reflect the fluid distribution condition under the formation condition, and the oiliness of the reservoir is correctly evaluated.

The present application provides a kind of laminated shale bedding seam porosity determination method, the laminated shale bedding seam porosity determination method includes: step 1, selects the laminated shale rock sample of a certain research block, carries out helium hole method porosity determination experiment, obtains the pore volume and porosity of the shale sample as a whole;Step 2, obtain the curve of porosity and permeability with net overburden pressure;Step 3, obtain pore compression coefficient and permeability sensitivity coefficient;Step 4, according to pore compression coefficient and permeability sensitivity coefficient, obtain the pore permeability power index;Step 5, obtain the maximum pore radius value and average pore radius value;Step 6, according to the calculation formula of pore permeability power index, calculate the laminated shale bedding seam porosity value.The laminated shale bedding seam porosity determination method has strong reliability and accuracy, provides effective technical support for laminated shale oilfield resource quantity evaluation and development scheme.

The invention provides a clastic rock reservoir overburden pressure physical property loss evaluation method and device, and the method comprises the steps: classifying cement in a target reservoir according to the sedimentary environment of the target reservoir, and obtaining a cement classification result; obtaining the content of different cement in the cement classification result; screening out a target cement according to the content; and evaluating the overburden pressure physical property loss of the clastic rock reservoir according to the target cement. According to the method, the porosity and permeability under different overburden pressures can be efficiently and accurately obtained in a mode of counting the types and the contents of the cement under the condition that a large-scale drilling column core and a displacement experiment are not carried out, so that the physical property loss rate of the clastic rock reservoir under the overburden pressures is evaluated.

The present application relates to the technical field of ground stress prediction, and particularly relates to a ground stress prediction method, system and device based on pre-stack elastic parameter inversion; the method comprises the following steps: S1, obtaining seismic data, and performing amplitude-preserving denoising processing on the seismic data; S2, solving elastic parameter reflectivity by using Zoeppritz linear equation, wherein the elastic parameter reflectivity comprises a density data body, a P-wave velocity data body and a Poisson's ratio data body; S3, performing denoising operation on the elastic parameter reflectivity; S4, obtaining an overburden pressure data body based on the density data body processed by the denoising operation in the S3 step; S5, obtaining a formation pore pressure data body based on the P-wave velocity data body processed by the denoising operation in the S3 step; S6, obtaining a ground stress prediction value based on the overburden pressure data body, the formation pore pressure data body and the Poisson's ratio data body; the signal-to-noise ratio and the accuracy of the pre-stack seismic inversion result are improved.

The invention discloses a method and device for determining collapsibility of a large-thickness loess site, and relates to the technical field of loess detection.The method comprises the steps that collapsibility judgment values of different depths are adopted for conducting collapsibility judgment on soil layer samples of all the depths; taking the soil layer sample with the maximum loess self-weight collapsibility coefficient as a representative sample; determining saturation correction coefficients of the soil layer samples which are judged to be collapsible soil layers by measuring collapsibility coefficients of representative samples under different initial saturations and overburden pressures; preparing a plurality of groups of cutting ring test pieces with different heights by adopting the representative samples, measuring soil sample self-weight collapsibility coefficients of the cutting ring test pieces at different heights, and further determining a size correction coefficient; respectively carrying out a standard collapsibility test and a triaxial compression test on the representative sample to determine a stress correction coefficient; and according to the size correction coefficient, the stress correction coefficient, the collapsible soil layer thickness and the saturation correction coefficient, calculating the self-weight collapsible deformation of the target loess site. According to the invention, the calculation accuracy of the site self-weight collapsibility is improved.

The present application relates to the technical field of coal mine geological data analysis, and specifically discloses a coal mine geological data analysis method based on three-dimensional modeling technology and a storage medium, which comprises the following steps: mine three-dimensional model construction, front mining wall danger analysis, mine surface mining danger analysis, roof stratum mining danger analysis, side wall mining danger analysis, and mine mining danger grade evaluation; the present application comprehensively analyzes the mining safety from four angles of the front mining wall, the surface, the roof stratum and the left and right side walls of the mine, improves the comprehensiveness of the mine mining safety analysis, analyzes the mining safety of the surface layer according to the surface deformation and the surface water pressure, improves the accuracy of the mining safety analysis of the surface layer, analyzes the mining safety of the roof stratum according to the rock thickness change and the overburden pressure change, and reduces the risk of mine collapse in the mining process.

The present application provides a kind of laminated shale gas permeability test method, comprising: step 1, select the laminated shale sample of certain study block, obtain the length L and diameter D of laminated shale;Step 2, measure the laminated shale gas permeability value under different confining pressures;Step 3, draw the curve of laminated shale permeability with net overburden pressure;Step 4, draw the curve of permeability-net overburden pressure logarithm;Step 5, according to the curve of permeability-net overburden pressure logarithm, obtain the inflection point value;Step 6, establish the curve of net overburden pressure-permeability in rectangular coordinate;Step 7, calculate the curve of laminated shale gas permeability and net overburden pressure relationship.The method accurately determines the laminated shale gas permeability value, has strong reliability and accuracy, provides effective technical support for laminated shale oilfield productivity prediction and development plan.

The present invention discloses a seismic formation pressure prediction method based on the Y-PPM pore physics model, which is applicable to the field of petroleum geophysical exploration. The method comprises: first, inverting seismic data from the target area to obtain velocity and density data, and then accurately determining the overburden pressure based on the density data. The Eaton formula and the Fillippone formula are then combined to establish a normal compaction trend formation velocity substitution model. A first correlation model between formation velocity and effective pressure is then established based on the Y-PPM pore physics model, and a second correlation model between effective pressure and formation pressure is established based on effective stress theory. Finally, a high-precision model between formation velocity and formation pressure is established based on the substitution model, the first correlation model, and the second correlation model.

The present application provides an overburden separation layer grouting and spouting emergency treatment process, through the development of orifice spouting pressure reduction pretreatment process, the pressure in the separation layer space is reduced to the overburden pressure of the key layer at the first time after spouting, the continuous expansion of the spouting channel and the continuous leakage of the slurry are inhibited, at the same time, the slurry flow direction is changed by spouting, the solid particles in the spouting channel are naturally precipitated to realize preliminary plugging, and low-pressure stable flow conditions are created for subsequent leakage stopping and grouting; then, the super-high water material grouting mode of thickening first and then thinning and gradient pressure increase is adopted, the large-scale spouting main channel is preferentially plugged by low water-cement ratio slurry, the secondary small fissure is filled by medium water-cement ratio slurry, and the fly ash and coal gangue slurry particles in the separation layer are widely cemented by high water-cement ratio slurry, realizing full-scale plugging from the main channel to the micro fissure, and at the same time, the in-situ reinforcement of the filling body in the separation layer space is completed, avoiding the closure of the separation layer space due to insufficient filling, and ensuring the subsidence reduction effect of the overburden separation layer grouting.

The present invention discloses a method for evaluating the collapse pressure of a directional wellbore under the synergistic effect of different strength criteria, comprising: utilizing well logging, drilling and completion, and indoor test data to determine the vertical depth of the drilled formation, the formation pore pressure, the overburden pressure, the maximum horizontal in-situ stress, the minimum horizontal in-situ stress, and the azimuth of the maximum horizontal in-situ stress, the rock cohesion, the rock internal friction angle, the rock Poisson's ratio, the rock porosity, the Biot coefficient, and the wellbore permeability; establishing a collapse pressure calculation model under different rock strength criteria; calculating the relative importance of different rock strength criteria; determining the weight coefficients of different rock strength criteria; and establishing a directional wellbore collapse pressure calculation model under the synergistic effect of different strength criteria. Due to the introduction of the weight coefficient, the present invention combines the advantages of other criteria, obtains the advantageous synergistic effect of different strength criteria, and can more accurately calculate the collapse pressure equivalent density value when a reasonable weight coefficient is given.

The invention discloses a quantitative evaluation method and device for different cause overpressure contribution degrees of an oil and gas reservoir, and the method comprises the steps: determining the vertical effective stress of an overpressure point based on the logging data and actually measured pressure data of a research region; respectively determining the maximum horizontal principal stress and the minimum horizontal principal stress of the overpressure point based on the extrusion tectonic stress and the rock Poisson's ratio of the overpressure point and the vertical effective stress; the average stress of the overpressure point is determined based on the overlying stratum pressure, the maximum horizontal principal stress and the minimum horizontal principal stress of the overpressure point; based on the average stress of the overpressure point and the average effective stress of the overpressure point at the equivalent depth point, the tectonic extrusion pressurization amount of the overpressure point is determined; determining an overpressure point sound wave velocity of an overpressure point based on a correlation curve of normal compaction section sound wave velocity-vertical effective stress of the research area; and based on the vertical effective stress of the overpressure point and the sound wave velocity of the overpressure point, the overpressure transmission pressurization amount of the overpressure point is determined, so that overpressure contribution degrees of different causes are determined, and a theoretical basis is provided for oil-gas exploration.

The invention belongs to the technical field of underground engineering similar material simulation tests, and particularly discloses underground engineering excavation and water inrush simulation test equipment and method. According to the invention, different rock stratum strike angles are accurately simulated in situ; the loading head is driven by the normal oil cylinder to apply rigid loading pressure to the sample so as to simulate the pressure of the overlying strata; the flexible air bag self-adapts to sample upper end surface deformation and applies continuous pressure; the water inrush supply unit is selectively communicated with any one or more first water supply connectors of the water storage box and supplies water with set pressure and flow, and water inrush positions are set at the top and the bottom of the simulation sample for water inrush; the loading pressure and the loading displacement of the normal loading unit, the loading pressure of the flexible loading unit and the pressure and the flow of water supplied by the water inrush supply unit are acquired in real time through the data acquisition unit, and data processing and output are carried out. In this way, rock stratum stress deformation and water inrush during underground engineering excavation can be accurately simulated.

The invention discloses a coal rock porosity determination method, device and equipment and a storage medium, which are applied to the field of geological exploration, and the optimal process full-diameter porosity of a full-diameter rock core and the optimal process small plunger porosity of a small plunger rock core are determined through a helium measurement method under multi-process conditions; establishing a first scale relationship between the porosity of the small plunger in the conventional process and the porosity of the small plunger in the optimal process, and establishing a second scale relationship between the porosity of the small plunger in the optimal process and the full-diameter porosity in the optimal process; establishing a third scale relationship between the effective stress porosity and the porosity of the conventional process small plunger; and establishing a correction model based on the first scale relation, the second scale relation and the third scale relation, and correcting the porosity of the small plunger in the conventional process based on the correction model to obtain the formation condition porosity. On the basis of optimizing process conditions, full-diameter and conventional small plunger coal samples are adopted for comparison measurement, influences of different pore pressures and overburden pressures are considered, and the accuracy of porosity data is improved.

The present application provides a drilling scheme selection method and apparatus based on three-dimensional seismic data. The corresponding method comprises: determining formation elasticity parameters of a target work area on the basis of three-dimensional seismic data and logging data of the target work area; on the basis of the formation elasticity parameters, determining overburden pressure at each depth in the target work area; on the basis of the logging data, the formation elasticity parameters, and the overburden pressure, respectively determining first pore pressure of a first formation in which abnormally high pressure is formed by a compaction mechanism and second pore pressure of a second formation in which abnormally high pressure is formed by a non-compaction mechanism; and on the basis of the formation elasticity parameters, the overburden pressure and the second pore pressure, determining a formation pore pressure coefficient, a collapse pressure coefficient and a fracture pressure coefficient of the second formation, to select a drilling scheme.