447 results about "Water saturation" patented technology

A porous media grouting test system and method taking temperature effects into consideration. The system comprises a porous media formation simulation model (1), a grouting system (2), a water level adjustment system, a formation temperature control system and a data analysis system, wherein the porous media formation simulation model (1) is used for simulating a porous media formation; the water level adjustment system and the formation temperature control system are used for simulating the conditions of different water saturation levels and different water temperatures and ground temperatures; and the data analysis system is used for comparing different time-series data collected by sensors such as a temperature sensor and a pressure sensor with data such as temperature data and pressure data that is obtained by means of coupled solving of a heat transfer equation and a momentum equation, so as to verify and analyze a grouting diffusion path. Free simulation of different water saturation levels is realized by means of a water level adjustment system, and simulation of different ground temperatures is realized by means of a formation temperature control system, thereby realizing the research on grouting diffusion under different water levels and different water temperatures and ground temperatures.

The invention discloses a dual-model-driven intelligent reservoir logging evaluation method, which comprises the following steps of: establishing a lithology identification logging data set based on a rock slice identification result and conventional logging data, and constructing a data model-driven lithology identification pre-training model; establishing a porosity prediction data set of different lithology based on a core porosity analysis result, and constructing a dual-model driven porosity prediction model of a data model and a knowledge model under the guidance of a lithology classification result; establishing a permeability prediction data set of different lithology based on a permeability analysis result, and constructing a dual-model driven permeability prediction model of a data model and a knowledge model under the guidance of a lithology classification result; on the basis of different lithologic saturation parameters measured in a laboratory, the water saturation of different lithologies is calculated in combination with physical property prediction results driven by double models of different lithologies and conventional logging data. The method can effectively solve the well logging evaluation problem faced by a complex reservoir.

The invention belongs to the technical field of petroleum engineering, and discloses a shale gas reservoir apparent permeability prediction method and a related device, and the method comprises the steps: obtaining data; judging a gas flow state; establishing a shale gas mass migration model; establishing apparent permeability models of capillary tubes with different sizes; obtaining a shale reservoir apparent permeability model; carrying out transfer learning; according to the method, the influence of the reservoir effective stress and the shale water saturation on the permeability is comprehensively considered, the neural network model is adopted to obtain the effective flow radius, and the prediction accuracy is improved; by introducing the permeability correction coefficient, dynamic correction of the original permeability value is realized, so that the actual permeability can be reflected more accurately; according to the method, by adopting transfer learning, a specific type of shale reservoir apparent permeability model is transferred to other conditions, so that the model can be used for predicting the permeability of different types of shale reservoirs, and the universality is effectively improved.

The invention relates to the technical field of rock sample oil-water saturation determination based on a nuclear magnetic technology, and provides a shale sample oil-water saturation intelligent determination method based on a two-dimensional nuclear magnetic technology, and the method comprises the following steps: collecting volumes, echo signals and signal-to-noise ratios of a preset number of rock samples; marking a target rock sample and a comparison rock sample, and determining a volume influence comprehensive interference degree and a noise amplification coefficient of a target echo signal; obtaining a denoised target echo signal according to the target echo signal, the volume of the rock sample corresponding to the target echo signal and the noise amplification coefficient of the echo signal; according to experiments of rock sample two-dimensional nuclear magnetic oil-water distribution, pore attributes and the like, a two-dimensional nuclear magnetic T1-T2 map is divided into an invalid pore area and an effective pore area of a rock sample corresponding to the two-dimensional nuclear magnetic T1-T2 map and an oil-water distribution area of the effective pore area, a fluid close to reservoir oil-water distribution is adopted to recover a two-dimensional nuclear magnetic spectrum of the rock sample, and the oil-water content corresponding to a nuclear magnetic signal is extracted; and obtaining a rock sample oil-water saturation determination result based on the nuclear magnetic technology.

The invention discloses a low-permeability gas reservoir productivity prediction method, a storage medium and a low-permeability gas reservoir productivity prediction device, and belongs to the technical field of low-permeability gas reservoir development. Based on the gas-water two-phase motion equation, establishing a gas phase productivity equation considering the high-speed non-darcy effect, the starting pressure gradient and the stress sensitive effect; establishing a water yield calculation formula considering the starting pressure gradient and the stress sensitive effect; the water-phase relative permeability is expressed on the basis of the relation between the gas-water relative permeability ratio and the water saturation; using a gas-water relative permeability model to express the gas-phase relative permeability considering the active degree of the water body; and substituting the gas phase relative permeability into the gas phase productivity equation. According to the method, the influence of the water body active degree, the starting pressure gradient and the stress sensitive effect on the productivity of the gas reservoir is considered, the multi-factor coupled productivity prediction model including formation water invasion is established, the technical problem that the productivity of the low-permeability gas reservoir is difficult to accurately predict through a traditional method is solved, and the development efficiency and economic benefits of the low-permeability gas reservoir are effectively improved.

The invention relates to the technical field of logging evaluation of a shale gas reservoir geologic model, and discloses a logging evaluation method suitable for the shale gas reservoir geologic model, which comprises the following steps: collecting and arranging logging data, including natural gamma, resistivity, interval transit time, density and neutron logging curves, based on geological data and logging data of adjacent wells, an initial geological model of the shale gas reservoir is established, a logging curve is preprocessed, including depth correction, environment correction, data smoothing, utilization of response characteristics of the logging curve, identification of cracks and stratification in the shale gas reservoir, and utilization of the logging data to calculate physical property parameters of the shale gas reservoir. According to the logging evaluation method, a plurality of reservoir parameters including the organic carbon content, the thermal maturity, the porosity, the permeability, the water saturation, the fracture development degree and the like can be obtained, and the comprehensive analysis of the parameters can more comprehensively reflect the reservoir characteristics, so that the accuracy of a geologic model is improved.

The invention discloses a shale hydrocarbon expulsion efficiency evaluation method, device, equipment and medium, and relates to the technical field of shale gas exploration and developing.The shale hydrocarbon expulsion efficiency evaluation method includes the steps that hydrocarbon generation quantity charts of shale under different total organic carbon TOC grades are constructed; testing the water saturation of the core sample of the shale to obtain the water saturation rate of the core sample; carrying out oil washing treatment on the rock core sample, and carrying out porosity test to obtain rock porosity and rock apparent density; obtaining a crude oil sample of a production layer where the core sample is located, and performing a crude oil physical property experiment to obtain crude oil density; when key parameters such as water saturation rate, rock porosity, rock apparent density, crude oil density and shale hydrocarbon generation quantity charts under different total organic carbon TOC grades of a core sample and key parameters of hydrocarbon release and migration in a hydrocarbon expulsion process are measured, a dynamic measurement process is adopted, and the dynamic measurement process can realize dynamic simulation of a hydrocarbon migration path; and finally, accurate evaluation of the shale hydrocarbon expulsion efficiency is realized.

The invention discloses a hydrate-containing porous medium resistivity model construction method considering hydrate heterogeneous distribution, and the method comprises the following steps: 1) manufacturing a rock core according to the rock composition of a target hydrate reservoir, and scanning the pore throat structure of the rock core through CT; 2) generating a hydrate in the core, and scanning the occurrence state of the hydrate through CT (Computed Tomography); 3) establishing a digital core model based on CT scanning data, and applying an electrostatic field; 4) changing hydrate saturation parameters in the model, and calculating the resistivity of the model through numerical simulation; 5) calculating the critical water saturation of the hydrate; and (6) fitting by taking the critical water saturation as a boundary to obtain a resistivity segmentation calculation model. According to the method, a hydrate-containing porous medium resistivity model is established based on a real rock core size, and an electric field simulation means is utilized to calculate a hydrate-containing porous medium resistivity value. In combination with CT scanning data, an undetermined coefficient of a porous medium resistivity calculation formula in a hydrate thermal decomposition experiment is obtained through electric field simulation, and a basis is provided for hydrate reservoir electric heating development.

The invention discloses a reservoir four-relation chart processing method, device and equipment and a medium, and relates to the field of oil well exploration, and the method comprises the steps: building a logging information parameter processing interpretation model, and determining parameters in an oil saturation model; based on the neutron-density intersection chart, calculating the distances from the logging response parameters to different lithologic curves as lithologic indication parameters; drawing a reservoir four-relation chart by taking the porosity of the stratum as an abscissa, the resistivity of the stratum as an ordinate and the lithology indication parameters as color mapping, drawing different water saturation scale marks in the reservoir four-relation chart, and in addition, taking the water saturation or the movable hydrocarbon saturation in the reservoir four-relation chart as a bubble radius; and projecting the logging response parameters of various stratum types and the explaining stratum parameter points into the reservoir four-relation chart, and establishing a logging explaining standard. According to the method, the dynamic change and internal relation among the four properties of the reservoir can be comprehensively and accurately displayed.

The invention discloses a method for evaluating the crude oil utilization rate during shale oil in-situ heating modification exploitation, and is applied to the field of oil development. The method comprises the following steps: (1) constructing a three-dimensional grid model of shale oil reservoirs between two horizontal wells, and determining parameters such as initial temperature, initial fluid pressure, initial porosity, initial oil saturation, initial gas saturation, initial water saturation and initial dissolved gas volume of three-dimensional grid units of each reservoir; (2) determining the pressure of each reservoir three-dimensional grid unit when the fluid pressure is balanced according to the shale oil layer section bottom hole pressure and the reservoir displacement pressure gradient; (3) according to the characteristics of a temperature field, a pressure field and the like of the in-situ heating shale oil reservoir, obtaining three-dimensional grid unit temperature and instantaneous fluid pressure parameters of each reservoir, and determining porosity and fluid saturation at each time point; and (4) according to the instantaneous fluid pressure and the balanced fluid pressure of the three-dimensional grid unit of each reservoir, determining the oil, gas and water production quantity and the production rate of the grid unit of each reservoir in combination with the oil, gas and water saturation.

The invention provides a crack pore medium multi-domain seismic inversion method and device, and relates to the technical field of geological prospecting, and the method employs a reflection coefficient calculation mode based on an accurate Graebner equation, and employs a Cauchy prior constraint to combine a target function constructed by a time domain and a frequency domain. The method realizes simultaneous inversion of three parameter profiles of porosity, crack weakness and water saturation, an accurate Graebner equation can accurately describe reflection coefficient characteristics of a crack medium, time domain inversion can enhance noise immunity, and frequency domain inversion can improve resolution, so that the accuracy, the noise immunity and the resolution of an inversion result are considered, and the method is suitable for large-scale popularization and application. And high-precision and high-resolution estimation of the porosity, the crack weakness and the water saturation is realized.

The invention relates to a digital core resistivity numerical simulation and saturation model construction method under deep overpressure and high temperature conditions, and relates to the technical field of oil-gas exploration, and the method comprises the steps: constructing a digital core under the overpressure condition, calculating the clay conductivity and formation water conductivity under the high temperature condition, and obtaining an overpressure and high temperature equivalent digital core model; based on an overpressure and high-temperature equivalent digital core model, through an electrical numerical simulation algorithm, the resistivity and the stratum factor F of water-saturated cores with different porosities phi are calculated, and an F-phi cross plot is constructed; and calculating digital core resistivity and resistivity increase coefficient RI of different water saturation Sw by using a numerical simulation algorithm, and constructing an RI-Sw cross plot. According to the method, a saturation model under the deep actual temperature and pressure conditions can be constructed through equivalence of pressure and temperature by utilizing a digital rock core numerical simulation technology.

The invention provides a method for evaluating the permeation enhancing effect of ultrasonic wave acting on a porous medium, which comprises the following steps: carrying out first NMR test on a dried, vacuumized and saturated sample to obtain a first saturated water T2 spectrum of the sample, and analyzing related parameters of the sample through the first saturated water T2 spectrum; performing a first ultrasonic permeation enhancing effect on the sample subjected to the first NMR test through ultrasonic waves, and performing a second NMR test on the sample every set time in the process to obtain a second saturated water T2 spectrum; after each second NMR test is finished, the sample is vacuumized again for water saturation, and the sample which is vacuumized again for water saturation is subjected to a third NMR test to obtain a third water saturation T2 spectrum; related parameters of the medium after the ultrasonic action at different time points are calculated through the third water saturation T2 spectrum, and the intensity of the ultrasonic cavitation effect is calculated according to the second water saturation T2 spectrum and the third water saturation T2 spectrum; and evaluating the permeation enhancing effect of the ultrasonic waves through the previous and later related parameters. According to the method, the ultrasonic cavitation intensity and the permeation increasing effect can be evaluated at the same time.

The invention relates to the technical field of water flooding gas reservoirs, in particular to a rock core displacement fluid saturation testing method and a testing device thereof.The method comprises the steps that S1, the original formation pressure and temperature of a gas reservoir are obtained; s2, obtaining a rock core, and testing physical property data of the rock core; then carrying out nuclear magnetic testing on the rock core; s3, saturating the rock core with formation water, and then carrying out nuclear magnetic testing; s4, carrying out gas drive water seepage test on the rock core according to the data in the S1, and obtaining the drive water quantity; s5, performing nuclear magnetic test on the depleted rock core; s6, obtaining the irreducible water saturation of the depleted rock core according to the nuclear magnetic test results of the steps S2, S3 and S5; s7, the total irreducible water saturation of the rock core is obtained according to the rock core physical property data, the displacement water amount and the irreducible water saturation of the rock core after exhaustion; the device comprises a drying oven, a first container, a second container, a core holder, a confining pressure pump, a displacement pump, a back pressure assembly, a receiving container and an electronic balance. The accuracy of fluid saturation determination can be improved.

The embodiment of the invention discloses a rock physical modeling method and device, electronic equipment and a storage medium. The method comprises the following steps: for a target rock to be subjected to rock physical modeling, determining a rock matrix modulus of the target rock; according to the rock physical property parameters of the target rock, irreducible water saturation of irreducible water in the target rock is predicted, and the isolated porosity of the target rock is obtained according to the irreducible water saturation; and based on the isolated porosity, adjusting the matrix modulus of the rock, and based on the adjusted matrix modulus obtained after adjustment, establishing a rock physical model of the target rock. According to the technical scheme provided by the embodiment of the invention, in the rock physical modeling process, the influence of the complex pore connectivity and the irreducible water saturation on the rock elastic parameters is considered, so that the characterization accuracy of the rock physical model established by the method on the rock elastic parameters can be effectively improved.

The invention provides a tight sandstone gas reservoir formation water division method based on mercury intrusion and online nuclear magnetic resonance, and relates to the field of gas reservoir formation water production, and the method specifically comprises the following steps: obtaining a tight sandstone core standard rock sample; cutting the rock core into two sections, and performing a high-pressure mercury injection experiment on the first section of the rock core; and scanning the nuclear magnetic resonance signal T2 spectrum curve of the rock core in the completely saturated water state and the area of the nuclear magnetic resonance T2 spectrum curve. And carrying out gas drive and nuclear magnetic scanning experiments. And sequentially increasing the displacement pressure differences to obtain a nuclear magnetic resonance correction curve under different displacement pressure differences. And drawing a water saturation and displacement pressure difference relation curve, and defining the critical pressure difference of different types of formation water production according to the curve form and the slope change rule. And processing the data to obtain the formation water production rule of the tight sandstone gas reservoir in different states. According to the technical scheme, the problem that in the prior art, the critical output pressure difference and the dynamic output rule of various types of formation water in different pore diameter ranges cannot be quantitatively represented is solved.

Methods and systems are disclosed. Methods may include obtaining well data along an interval of a well and identifying a first candidate interval within the interval using the well data. The well data includes acoustic data and porosity data. A formation surrounding the well within the first candidate interval includes micropores. The methods may further include determining mechanical parameter data along the first candidate interval based on the acoustic data and identifying a second candidate interval within the first candidate interval based on the mechanical parameter data and the porosity data. The methods may still further include determining water saturation data along the second candidate interval based on the well data, identifying a productive interval within the second candidate interval based on the water saturation data and a water saturation threshold, and determining a completion plan for the well based on the productive interval.

The invention discloses a well logging water saturation calculation method and device, equipment and a medium, and relates to the technical field of oil and gas field exploration and development geological research, and the method comprises the steps: preprocessing a well logging curve of a crack and pore composite compact sandstone reservoir, and calculating the parameter information of a crack according to the processed curve; correcting the deep lateral resistivity value in the processed curve to obtain a corrected resistivity value; calculating a target exchange coefficient and a resistance increase rate of the rock core; determining a logging cementation index according to the parameter information of the fracture and the target exchange coefficient, dividing reservoir types, and fitting the core water saturation and the resistance increase rate of different reservoir types to obtain fitting results; obtaining a logging saturation index and a logging lithologic coefficient according to an Archie formula and a fitting result, and determining the logging water saturation based on the corrected resistivity value, the logging cementation index, the logging saturation index and the logging lithologic coefficient. And the logging water saturation can be accurately calculated.

Method and systems are provided that characterize a geological formation, which involve collecting or obtaining electrical signal data that results from interaction of electrical signals with the formation. The electrical signal data is processed to determine data characterizing relative permittivity and conductivity of the formation. The data characterizing relative permittivity and conductivity of the formation are used as inputs to models to determine data characterizing water saturation of the formation, particularly useful in formation evaluation and reservoir saturation dynamic monitoring in fresh water and mixed salinity environments.

The invention innovatively provides a three-water electric conduction model parameter calculation method based on nuclear magnetic resonance constrained conventional logging, aiming at the technical problems that three-water electric conduction model parameters are too many, and the model parameters can be determined only by using a large amount of rock core experiment data such as mercury injection, rock electricity experiments, clay analysis and cation exchange capacity in the prior art. According to the calculation method, the free fluid porosity, the micro capillary water porosity and the clay water porosity which are obtained through nuclear magnetic resonance logging interpretation are substituted into a formula of a three-water electric conduction model represented by conventional logging parameters and are combined with the porosity, the shale content, the irreducible water saturation and other parameters which are explained through conventional logging; finally, calculation of all model parameters can still be completed under the condition of not depending on experimental data, and during parameter calculation, the calculation precision is improved by adopting the optimization algorithm assistance of multiple groups of data depending on the characteristic that logging data has a big data sample.

According to the method for predicting the reservoir water saturation by combining an ordinary differential equation and a neural network, logging data of a well are extracted from a petroleum reservoir geologic model, the logging data obtained after data preprocessing are firstly sent into a convolutional neural network for data feature amplification, then the logging data enter a long-short-term memory network to calculate the hidden layer state and the cell state, and the reservoir water saturation is predicted. Mainly, a fixed-step-length fourth-order Runge-Kutta method is used for numerical solution of a differential equation to obtain a new hidden layer state, so that the training prediction precision is improved, and finally, optimal model parameters are used for predicting the reservoir water saturation. According to the method, the dynamic change rule of effectively capturing the hidden state by introducing the ordinary differential equation is emphatically considered, the prediction precision and stability of the water saturation of the model are improved, and a more accurate basis is provided for the decision-making process of oil and gas field development.

The invention provides a method and system for determining gas-water distribution of a tight sandstone gas reservoir, and the method comprises the steps: building a multi-factor hierarchical control mode of the gas-water distribution of the tight sandstone gas reservoir, and embedding control factors step by step in the modeling process of bound water and movable water based on the multi-factor hierarchical control mode of the gas-water distribution, and a total water saturation model is established by taking a bound water and movable water merging model as spatial constraint, so that quantitative characterization of gas-water distribution under multi-factor control is realized.

The present application relates to new systems and methods of quantifying hydrocarbon saturation using measured acoustic logs. The methods and systems herein can accurately quantify the water saturation and hydrocarbon percentage in a low resistivity low contrast shaly sand reservoir where previous methods would indicate the reservoir was wet. In an embodiment, the disclosed system utilizes acoustic logging equipment or tools and techniques to transmit and / or record acoustic signals. Acoustic logging equipment operates by generating acoustic signals and detecting the acoustic signals after the acoustic signals pass through one or more geologic formations.

The invention provides a deep water gravity flow gas field reservoir water saturation earthquake prediction method based on TDCN-TransNet. The method comprises the following specific steps: a TDCN-TransNet network architecture comprises an input processing layer, a dual TWT position code, a TDCN module, a Transformer encoder layer and an output layer; mapping the features to a hidden dimension in an input processing layer through linear full connection; a dynamic Gaussian convolution kernel and a CBAM attention mechanism are embedded in the TDCN, and modeling of a nonlinear relation between an elastic parameter and saturation is enhanced through multi-scale time sequence feature extraction; tCBlock is integrated on a Transform encoder layer, and long-distance sequence dependence is captured by using attention pooling and an SE channel excitation mechanism; a TWT position code is introduced between the TDCN and the Transform, and sequence position information is enhanced; constructing a combined loss function of a mean square error and L2 regularization; finally, training and reasoning are conducted based on the model, and high-precision water saturation prediction is achieved. The method provided by the invention has high generalization and accuracy, and shows excellent prediction performance in a complex geological environment of a deepwater gravity flow reservoir.

The invention belongs to the technical field of oil and gas development, and discloses a formation water comprehensive compression coefficient measuring method and system.The method comprises the steps that a fracture network distribution rule and pore structure parameters are extracted; preparing a micro-fluidic chip; preparing formation water fluid containing dissolved gas, and injecting the formation water fluid into the micro-fluidic chip; carrying out a formation water failure development experiment under a reservoir in-situ condition, and recording gas-water saturation and pressure change in the micro-fluidic chip; quantifying the variation of the volume of the precipitated bubbles along with the pressure drop, and calculating a first compression coefficient contributed by the dissolved gas part and a second compression coefficient contributed by the formation water body part; and superposing the two coefficients to obtain the formation water comprehensive isothermal compression coefficient. According to the method, the formation water gassing expansion process can be monitored in real time, the formation water comprehensive isothermal compressibility coefficient can be more accurately calculated in combination with gas-water saturation and pressure change, and the problem that fluid seepage and fluid characteristics of the fractured low-porosity sandstone gas reservoir cannot be fully reflected is solved. The system has the same advantages as the method.

The invention discloses a soil solidification effect detection and analysis system and method, and relates to the field of soil solidification effect detection.The soil solidification effect detection and analysis method comprises the steps that based on the sedimentation characteristics of a solidification material, soil is divided into a bottom sedimentation sudden change zone, a middle sedimentation gradual change zone and a top sedimentation stable zone in the depth direction, and the minimum operation thickness of a sampling tool serves as the reference layer thickness; dividing non-equidistant sampling layers according to different multiples in each settlement zone to intercept columnar soil samples; performing an initial dynamic load test on the original soil sample, then performing circulating saturated water drying treatment on the same soil sample, and applying the completely same dynamic load mode again; a water circulation effect in a natural environment is simulated by performing vacuum water saturation and constant-temperature drying circulation treatment on a soil sample for multiple times and combining a dynamic load test after water damage. Through non-equal-interval stratified sampling and multi-round dry-wet cycle testing, stratified dynamic and high-precision quantitative evaluation of the water damage resistance of soil solidification is achieved.

The invention discloses a laboratory adsorption gas calculation method based on isothermal adsorption-nuclear magnetic resonance combined measurement, and relates to the technical field of exploration geophysics. According to the invention, on the basis of isothermal adsorption-nuclear magnetic resonance combined measurement experiment, 23MHz nuclear magnetic resonance experiment is utilized; nuclear magnetic signal conversion of bound water-adsorbed state methane is carried out through nuclear magnetic resonance T2 spectrums of coal rocks with different water saturations and T2 spectrums measured through a coal rock isothermal adsorption-nuclear magnetic resonance combined measurement experiment to obtain the hydrogen content of the adsorbed state methane, then the amount of substance of the adsorbed state methane is obtained, and finally the volume of the adsorbed state methane is obtained. The method comprises the following steps: firstly, measuring and determining the content of bound water in the coal rock by adopting a 25mm sample tube and the current minimum nuclear magnetism callback interval, then carrying out bound water-adsorbed gas nuclear magnetism signal conversion on the sample tube used in an isothermal adsorption-nuclear magnetism combined measurement experiment to obtain the hydrogen content of the adsorbed gas, further obtaining the amount of substance of the adsorbed gas, and finally obtaining the volume of the adsorbed gas.

The invention discloses a device and a method for rapidly evaluating physical and mechanical properties of waste concrete. Comprising a test box cover plate, a blower nozzle, a drying test bin top plate, a heating device, an aggregate bin, a drying test bin water outlet, a water storage tank, an aggregate bin bottom plate with a force sensor, a vibrating screen, a screen residue bin bottom plate with a force sensor, a pressurizing device, a water saturation test bin water outlet, a water saturation test bin top plate, a water injection nozzle, an infrared distance measuring sensor, a pressurizing opening and a control system. The drying test bin is connected with the water saturation test bin. According to the invention, the compressive strength, softening coefficient and crushing index of the waste concrete can be tested, the test time is obviously shortened, the intelligent degree of the test process is high, the physical and mechanical properties of the waste concrete can be more comprehensively evaluated, and the resource utilization of the waste concrete is promoted.

The present application relates to new systems and methods of quantifying hydrocarbon saturation using measured acoustic logs. The methods and systems herein can accurately quantify the water saturation and hydrocarbon percentage in a low resistivity low contrast shaly sand reservoir where previous methods would indicate the reservoir was wet. In an embodiment, the disclosed system utilizes acoustic logging equipment or tools and techniques to transmit and / or record acoustic signals. Acoustic logging equipment operates by generating acoustic signals and detecting the acoustic signals after the acoustic signals pass through one or more geologic formations.

The invention belongs to the technical field of oil and gas reservoir engineering and multiphase seepage dynamic monitoring, relates to a characterization method of seepage behaviors of multiphase fluid in a porous medium, and particularly provides a dynamic construction method of a multiphase displacement capillary pressure-saturation relationship based on nuclear magnetic resonance. Comprising the following steps: S1, acquiring a low-field nuclear magnetic resonance relaxation spectrum of a porous medium in a gas-water two-phase displacement process; s2, determining two-phase fluid interfacial tension, a wetting contact angle and a rock surface relaxation rate; s3, determining the dynamic cut-off relaxation time of the displacement stage; s4, calculating equivalent capillary pressure; the residual water saturation is calculated, and the equivalent capillary pressure is the capillary pressure corresponding to the current displacement stage and is used for constructing a capillary pressure-saturation curve. According to the method, the capillary pressure change in the porous medium can be obtained only through spectral analysis without a centrifugal or mercury injection experiment.