4730 results about "Rock core" patented technology

A method of producing liquid hydrocarbons from a hydrocarbon-bearing rock in situ in a geological formation begins with exploring the formation by drilling a plurality of boreholes into the formation and taking core samples of the hydrocarbon-bearing rock and at least one overburden layer. Electrical parameters of the hydrocarbon-bearing rock and the overburden layer are determined, as well as a roughness of a boundary between the hydrocarbon-bearing rock and the at least one overburden layer. These electrical parameters are used to construct a computer model of a portion of the hydrocarbon-bearing rock and at least one overburden layer, the computer model based upon modeling the formation as a rough-walled waveguide. This computer model is used to simulate propagation of radio frequency energy within the hydrocarbon-bearing rock, including simulation of radio frequency wave confinement within the hydrocarbon-bearing rock, at several frequencies and temperatures. A frequency for retorting is selected based upon simulation results. Radio frequency couplers are installed into at least one borehole in the hydrocarbon-bearing rock and driven with radio frequency energy to heat the hydrocarbon-bearing rock. As the rock heats, it releases carbon compounds and these are collected.

The present invention provides methods and apparatus for simulating well bore conditions before and after cementing therein. The methods of the invention are basically comprised of the steps of circulating a drilling fluid through a closed test cell containing a permeable rock core while maintaining a selected pressure differential across the rock core to form a layer of filter cake thereon, circulating a filter cake removal fluid through the test cell to simulate the clean-up of the well bore and then determining the condition of the rock core with respect to the effectiveness of the filter cake removal fluid thereon.

The invention relates to a supercritical carbon dioxide drive physical analogue device, which belongs to the technical field of petroleum engineering and technology. The device adopts two paratactic simulation core devices to be connected with an injecting system, and each simulation core device is provided with an outlet measuring system; the injecting system injects formation water, crude oil and supercritical carbon dioxide to the simulation core devices, and a temperature and pressure measuring and controlling system is adopted to control the temperature set value and the pressure value of the whole system, and the outlet measuring system is adopted to measure the volumes of the carbon dioxide, the formation water and the crude oil which pass through the simulation core devices. After the CO2 gas is cooled and liquefied, the CO2 gas is pressurized and heated up to the supercriticality, and the difficulty of the accurate measurement of the injected CO2 flow; by adopting a double-tube model, the fingering and cross flow phenomenon during the driving process of the heterogeneous reservoir CO2 can be simulated; the design pressure of the device is 0 to 40 MPa, the design temperature is 0 to 180 DEG C, and the device is mainly applied to the research on supercritical CO2 miscible drive, non-miscible drive, continues gas drive or water and gas alternate drive.

The invention provides a quantitative characterization method of low penetration double-medium sandstone oil reservoir microscopic aperture structure, which comprises the following steps: selecting experiment samples, effectively combining various experiments, distributing samples, processing and analyzing experiment test data, combining macroscopic background and microscopic rock core, and combining static state analysis and dynamic production reality, thereby realizing quantitative characterization of ultra-low penetration double-medium sandstone oil reservoir microscopic aperture structure from qualitative analysis and semi-quantitative evaluation. The invention has the advantages that more comprehensive influence factors and micro crack, aperture throat parameter and nuclear magnetic resonance movable fluid parameter are considered, so the characterization result can better reflect change characteristics of ultra-low penetration double-medium sandstone oil reservoir microscopic aperture structure, which are consistent to the production exploitation real cases of the oil field, thereby effectively avoiding one-sidedness and limitation of single aspect evaluation result.

A pressure and temperature core sampler comprises a tool for recovering cores specifically enabling the evaluation of methane hydrate resources. Because methane hydrate tends to decompose under conditions of pressure decrease and/or temperature increase as the samples are retrieved to the surfaces a coring tool in accordance with the present invention provides a self-contained system for retrieving core samples at or near in situ pressure while cooling the core sample. The coring tool is preferably a wire line retrievable device that provides for nearly continuous coring during the drilling operation.

The invention discloses a high-resolution digital rock core modeling method. The high-resolution digital rock core modeling method comprises the following steps: firstly, scanning a rock core by X-ray CT (computed tomography); then acquiring the rock throat radius distribution from rock core mercury data, acquiring the rock core porosity radius distribution from rock core nuclear magnetism data, intercepting the part the pore throat radius of which is less than the CT scanning resolution as an input parameter of a random network method, wherein the selected intercepted value is relevant to the CT scanning resolution; comparing the digital rock core porosity obtained by CT scanning with the experiment measurement porosity, calculating the size of the lost porosity of the digital rock core by CT scanning, and constructing a porosity network model by utilizing the intercepted pore throat radius distribution by adopting the random network method, wherein the porosity of the generated network model is consistent with the porosity lost in CT scanning; and converting the porosity network model into the micro porosity digital rock core by applying gridding method, and overlapping the digital rock core constructed by a mercury injection nuclear magnetism method to the digital rock core scanned by CT by adopting a multi-scale integration method. The method breaks through the restriction of CT scanning resolution.

An apparatus made according to one embodiment may include a chamber configured to receive a core at a receiving end of the chamber and a cutting device configured to cut the core at a location distal from the receiving end of the core chamber. A method according to one aspect of the disclosure may include drilling into the formation to retrieve a core, receiving the core into a chamber at an open end of a chamber, and cutting the core uphole of the open end of the chamber so as to continue to receive the core into the chamber as the drilling continues.

The invention relates to an experimental apparatus and a method for researching response characteristics of natural gas hydrate stratum to drilling fluid intrusion. The apparatus comprises a drilling fluid cycling mechanism, a high and low constant temperature experiment box, a gas permeability mechanism, a water / gas injection mechanism, a confining pressure tracking mechanism, a back pressure mechanism, a detection mechanism, an outlet metering mechanism, a rock core transferring mechanism, a sampling mechanism and an industrial control computer. The experimental methods based on the apparatus comprise an experimental method for hydrate deposit gas permeability, an experimental method for intrusion of drilling fluid to hydrate deposit and dynamic monitoring of response characteristics of the hydrate deposit during the intrusion process, and a method for fidelity transferring of hydrate deposit core. The invention provides an early stage indoor research on response characteristics of natural gas hydrate stratum to drilling fluid intrusion, so as to master influence rules of the drilling fluid intrusion on hydrate stratum physical properties, realize simulating fidelity transferring of a sample containing hydrate deposit and provide basis for future hydrate stratum exploitation and drilling safety and logging accuracy interpretation.

The invention relates to a test device and a method for simulating acid etching crack flow guide capability. The test device consists of a liquid storage tank, a diaphragm pump, a pipeline electric heating sleeve, a flow meter, a flat plate clamping device, a pressure return valve, a condensing pipe, a waste liquid tank, a data collection and control panel and the like, wherein the inner side of the clamping device is provided with a temperature sensor and a pressure sensor, both ends of the lamping device are provided with small liquid inlet holes and small liquid outlet holes, the inside of the clamping device is provided with a liquid inlet piston and a liquid outlet piston, a rock core chamber is arranged between the liquid inlet piston and the liquid outlet piston, the clamping device is connected with a pressure machine, and the diaphragm pump, the pipeline electric heating sleeve, the flow meter, the temperature sensor and the pressure sensor are all connected with the data collection and control panel and a computer. The test method comprises the following steps; cutting the rock into rock core samples conforming to the standard flow guide chamber, and sealing and curing the rock core samples; placing the rock core samples into the rock core chamber; adopting a gasket for simulating the crack width; sequentially opening a clear water storage tank and an acid liquid storage tank; starting the computer, and inputting experiment parameters; and calculating the flow guide capability of the acid etching cracks of the rock core samples. The invention can simulate the real conditions of the underground acid etching crack forms, and can meet the requirements of the acid etching crack flow guide capability test under different environment conditions.

The invention discloses a determining method for a stratum high-temperature high-pressure gas-phase and water-phase relative permeability curve. The determining method comprises the following steps: S1, preparing a rock core; S2, preparing fluid; S3, carrying out a single separation test on balance gas and balance stratum water; S4, saturating the rock core with water; S5, carrying out a connecting flow and raising the temperature to generate a pressure; S6, carrying out a balance water-phase permeability Kw test; S7, carrying out a gas-driving-water process relative permeability test; S8, correcting an accumulated water yield amount W(t) and an accumulated gas yield amount G(t); converting a value recorded under a ground condition to a stratum condition; and S9, calculating a water-phase relative permeability rate Krw and a gas-phase relative permeability rate Krg at each moment, and a gas-containing saturation degree (Sge) of a rock sample outlet end face. The determining method for the stratum high-temperature high-pressure gas-phase and water-phase relative permeability curve has the beneficial effects that high-temperature and high-pressure conditions of a real gas deposit stratum are effectively simulated and the influences on rocks and the fluid by the high-temperature and high-pressure conditions of the stratum are sufficiently considered; a determined result meets the actual production and the usable value of experimental data is high; the disadvantages in an existing determining method are overcome.

The invention provides an analog measurement method and a device of oil saturation in strata, which belong to a geophysical exploration testing method and an analog device. The analog measurement method of the oil saturation in the strata comprises the steps of simulating an actual stratum (manufacturing an artificial cemented rock core model), arranging an analog well, arranging an oil-water saturation monitoring system in the artificial cemented rock core model, constructing an electric field at the periphery of the wall of the well, obtaining the oil saturation illustrative charts of different pervious courses by measuring the change of the resistivity of the rock core model and the like. The method not only can well simulate and measure the underground geological condition but also can further learn the position of the residual oil of a reservoir and the change rule of the saturation, thereby learning and determining the oil accumulation reserves and the grade in the simulated stratum.

A method of evaluating a reservoir includes a multi-energy X-ray CT scan of a sample, obtaining bulk density and photoelectric effect index effect for the sample, estimation of at least mineral property using data obtained from at least one of a core gamma scan, a spectral gamma ray scan, an X-ray fluorescence (XRF) analysis, or an X-ray diffraction (XRD) analysis of the sample, and determination of at least one sample property by combining the bulk density, photoelectric effect index, and the at least one mineral property (e.g., total clay content). Reservoir properties, such as one or more of formation brittleness, porosity, organic material content, and permeability, can be determined by the method without need of detailed lab physical measurements or destruction of the sample. A system for evaluating a reservoir also is provided.

The invention discloses a method for constructing a multi-scale digital rock core based on fusion of a CT scanned image and an electro-imaging image. The method is characterized by extracting a large-scale pore and rock skeleton from the electro-imaging image, calculating partial porosity distribution and pore dimension distribution thereof, and constructing a large-scale three-dimensional digital rock core in radial direction; meanwhile, extracting a small-scale pore and rock skeleton from the CT scanned image, calculating partial porosity distribution and pore dimension distribution thereof, and constructing a small-scale three-dimensional digital rock core in depth longitudinal direction; and selecting horizontal sections, the depth of which are same, of the large-scale three-dimensional digital rock core and the small-scale three-dimensional digital rock core respectively, fusing the horizontal sections to generate a multi-scale two-dimension slice having small-scale pores and large-scale cracks and holes, and constructing a three-dimensional digital rock core through the multi-scale two-dimension slice, thereby solving the problem of constructing a multi-scale three-dimensional digital rock core of unconventional reservoir of shale, tight sandstone and carbonate rock and the like, and enabling the digital rock core module to be same with the actual rock to the largest degree.

The invention belongs to the technical field of artificial rock core preparation, and in particular relates to a preparation method of an artificial rock core of jointing shale. The method comprises the following steps: mixing and stirring cement, quartz sand, clay and gypsum powder; adding a small amount of cereal and scraps of paper into the mixture, adding water into the mixture and stirring uniformly; casting the mixture in a layered manner to form a cement test sample; and coating lubricating oil between every two layers, and drying the cement test sample for molding, thereby obtaining the artificial rock core of the jointing shale. By the preparation method, the cement test sample with certain fracture development, bedding development and brittleness can be obtained, and the mechanical properties of a bedding plane (1), a natural fracture (2), a hydraulic fracture (3) and the like of the jointing shale rock can be simulated relatively accurately, so that shale oil and gas can be developed effectively. According to the preparation method, the used materials are simple, the cost is low, and the operation is simple and convenient.

The invention relates to petroleum well-logging technology, in particular to a method for determining stratum water saturation. The method comprises the following steps: selecting a serial core of geologic feature; obtaining porosity Phi of the core and saturated core stratum water specific resistance Rw; and solving and substituting cementation index m(Rw, Phi) and saturation index n(Rw, Phi) ina common Archie water saturation computation model to calculate accurate stratum water saturation Sw. The method realizes corresponding change along with different physical properties of reservoir stratums and changes in stratum water specific resistance to ensure more accurate and reliable results, thereby having better application effect.

The invention discloses a method for reconstructing a digital rock core and pore network model based on a random fractal theory. The method comprises the following steps of based on the multiple fractal features of a porous medium, performing fractal representing on a capillary pressure curve obtained by the conventional mercury intrusion method, inferring fractal expressions of random distribution density function, average value and variance by a random distribution theory, and combining the random theory and the multiple fractal theory to construct a digital rock core, so as to rapidly construct a three-dimensional micro-network model. The method has the advantages that the cost is low and is reduced; the capillary pressure curve is measured by the mercury intrusion method, the full-section rock core is used in experiment, and a micro-pore structure is fully displayed. According to the method, the computing method is simple and convenient, and the advanced method is adopted; the micro-pore structure of reservoir rock is complicated and irregular, and an extremely complicated system cannot be accurately described by the traditional classical theory, so after the method combines the multiple fractal theory and the random distribution theory, the micro-pore structure can be accurately represented, and the method is easily implemented by programming.

A quantitative calculation method for oil (gas) saturation of fractured reservoir during petroleum exploitation is provided. The method comprises: obtaining the fracture porosity and calculating resistivity index at different depth of fractured reservoir with known full diameter core data and imaging logging data; establishing the percolation network model of matrix and fracture combination with known pore structure feature; calibrating the numerical simulation results obtained from percolation network model based on the data of core experiment and sealed coring analysis results, then obtaining the relationship between the resistivity index (I) and water saturation (Sw) at different fracture porosity; calculating the oil (gas) saturation of fractured reservoir through selecting an interpolation function. The oil (gas) saturation calculated with said method is 0.67, however 0.49 with common method in some fractured reservoir. The accuracy is improved by more than 0.18 in the studied fractured reservoir.

A wireline-conveyed side-wall core coring tool for acquiring side-wall core from a geological formation for performing in-situ side-wall core analysis. The coring tool has a core analysis unit operable to measure geophysical properties of an acquired side-wall core. The measured geophysical properties may be used to determine the success of the acquisition of side-wall cores by the coring tool. The core analysis unit is operable of performing an in-situ interpretation of measured geophysical property of the side-wall core and transmitting in near real-time the measurements or the interpretation results to surface data acquisition and processing apparatus.

The invention provides a high-temperature high-pressure clamp for testing rock core by nuclear magnetic resonance, which is applied to rock core dynamic experiments in a laboratory. The clamp mainly comprises an annulus pressure part, a high-temperature heating part, a displace part and a nuclear magnetic resonance part, wherein a sealing end cover and a lock nut are arranged at two ends of a cavity of the clamp; an annulus pressure oil inlet pipe and an annulus pressure oil drain pipe pass through the sealing end cover and are communicated with the cavity of the clamp; a spiral heat-conducting oil pipe is arranged between an insulating shell and the cavity of the clamp; two cylindrical rock core tops and sealing members are arranged in a fluorine rubber tube; a displacing oil inlet pipe and a displacing oil outlet pipe are fixed at two ends of the cylindrical sealing members; a nuclear magnetic resonance coil frame is arranged in the cavity of the clamp; and a nuclear magnetic resonance coil is arranged in an annular space formed between the outer wall of the nuclear magnetic resonance coil frame and the cavity of the clamp. The clamp has the advantages of simulating temperature and pressure of the rock core in the stratum to ensure that a nuclear magnetic resonance instrument can measure the physical parameters of the rock core under the condition of simulating the stratum.

The invention provides a complicated rock core preparation method based on CT scanning and 3D printing. Based on a combined technology of CT scanning and 3D printing, the reappearance of an underground rock pore structure characteristic is realized, and the visualization of oil-gas-water distribution inside a rock core can be achieved. Through a 3D printing technology, the visualization and actualization of the digital rock core and a network model can be achieved, and the underground core pore structure can reappear in a real object form. More importantly, with the continuous input and development of unconventional oil-gas fields such as carbonate rocks, shale oil and gas and compact oil and gas, the complicated rock core preparation method has the advantage that by using the combined technology of CT scanning and 3D printing, a new thought and method is provided for representation and preparation of special rock cores.

The invention relates to a dry ice sublimation hole bottom refrigerating and pressure keeping sampler and a sampling method. The device is mainly composed of a suspension differential action mechanism, a single action mechanism, a control mechanism, a refrigerating mechanism and a pressure keeping mechanism. The method comprises: using dry ice as refrigerant, alcohol as refrigeration assisting catalyst and secondary refrigerant, and applying low temperature alcohol to the hole bottom to refrigerate the rock core; closing a ball valve to keep pressure of the rock sample so as to inhibite the decomposition of the hydrate rock core; dismounting a blocking tube and a drill bit when sampling, dismounting a clamp spring and a clamp spring seat, pulling out a half combining tube and the rock core from the rock core tube, and using a liquid nitrogen holdup vessel or a high pressure container to keep the rock core sample. When drilling for sampling the rock core, the external tube and the drill bit gyre, but the internal tube assembly does not gyre, thus avoiding the damage of mechanical force to the rock core caused by the gyrus of the drilling tool to a larger degree, improving the rock core sampling rate, integrity and representativeness more effectively, and realizing pure refrigeration sampling as well as a combination of refrigeration sampling and rock core pressure keeping; compared with the prior art, the invention has simple process, convenient operation and greatly reduces the cost.

The invention relates to a hole bottom freezing cord coring drill and a coring method thereof. In the invention, liquid nitrogen is taken as a refrigerant; the liquid nitrogen absorbs heat in the gasification process so as to freeze a core at a hole bottom and inhibit a natural gas hydrate from being decomposed. The drill comprises an outer tube assembly and an inner tube assembly; and in the process of acquiring the core, a sand hitch is utilized to drag the inner tube assembly out from the outer tube assembly, an end cover and a clamp spring are dismounted, a semi-closed tube and a core sample are pumped out together from a core tube, the two ends of the semi-closed tube are sealed by rubber plugs, and the core sample and the semi-closed tube are stored in a liquid nitrogen hold-up vessel or a high-pressure container together. The invention has the advantages that rapid freezing can be realized, and the freezing effect is good; since cord coring and hole bottom freezing are combined, rapid coring without lifting the drill is achieved; in the drilling process, the inner tube assembly does not rotate, thus damages on a hydras core caused by mechanical force generated by rotation of the drill is avoided to a greater degree, the percentage of coring, the core integrity degree and the representativeness are more effectively improved; and semi-closed tube type rapid ground surfacesampling is adopted, thus the core can be rapidly obtained from the ground surface.

The invention discloses a lithology identification method. The lithology identification method comprises the steps that firstly, conventional three-porosity (sound waves, density and neutrons) logging measured values of N rock core samples are obtained through the steps of thin section authentication, X-ray diffraction analysis, rock core true depth determination and the like; secondly, the relative distance between two parameters of conventional three-porosity logging is obtained, and the quantitative relation between the relative distance of the two parameters and primary mineral components obtained through X-ray diffraction total rock analysis is obtained according to the relative distance of the two parameters and the mineral components of the N rock core samples; thirdly, rock classification based on the relative distance of the two parameters is established and can be applied to lithology identification of fine grain sedimentary facies area logging, and continuous lithology identification can be carried out on well stratums without core sampled.

The invention discloses a man-made rock core with a multi-pore structure and a preparation method of the man-made rock core. The preparation method comprises the following steps: preparing rock debris, inorganic salt particles and thin metal sheets; uniformly mixing the rock debris with an epoxy resin cementing agent; when adding a mixture into a mould, randomly embedding the designed inorganic salt particles and/or the thin metal sheets; solidifying; detaching the mould and taking out the man-made rock core; immersing the man-made rock core in distilled water and dissolving the inorganic salt particles to form dissolving holes; immersing or leaching the rock core by corresponding acid or alkali to form cracks; and finally, washing the man-made rock core with distilled water, and drying to obtain the man-made rock core with the multi-pore structure. According to the man-made rock core provided by the invention, the cracks and dissolving hole parameters of the rock core can be quantitatively controlled; the obtained man-made rock core is very similar with a natural rock core, so as to provide high-quality, low-cost and pollution-free experimental materials for simulation and test of physical properties including waves, seepage, conductivity and the like of rock.

A tool for use in the treatment of a formation penetrated by a well bore, the tool comprising a tubular core having at least one opening therein for the discharge of pressurized fluid from within the core first and second axially spaced apart sealing members disposed on the core for sealing between the core and the well bore, the at least one opening in the core being located between the first and second sealing members; and a third sealing member disposed downhole relative to the first and second sealing members for sealing between the tool and the well bore.

The invention discloses a method for judging the reservoir fluid type of a difference between density porosity and neutron porosity and relates to the technical fields of oil and gas logging and geology and core test analysis. The method comprises the following steps: 1) accurately calculating the shale content, the rock composition, the density porosity and the neutron porosity of a reservoir bycore data calibrating logging and logging data environmental correction; 2) removing the influence of factors of lithology, well diameter and mud invasion on density and neutron data; and 3) establishing standards for judging the reservoir fluid type by utilizing the response difference of the density and the neutron data to gas and formation water and by comparing the values of the density porosity and the neutron porosity. When the invention judges the reservoir fluid type by utilizing the density and the neutron data, non-fluid influencing factors, such as lithology, borehole conditions, mud invasion and the like are removed, therefore, influence features of different fluids to the density and the neutron data can be truly reflected, and the coincidence rate for judging the reservoir fluid type can be enhanced to above 90 percent from the existing 70 percent.

The invention discloses an identification method of the deposition and diagenetic integrated phase of clastic rocks. The method comprises the steps of 1) defining the deposition and diagenetic integrated phase based on a rock core; and 2) identifying the deposition and diagenetic integrated phase by utilizing a logging curve. The invention brings forward the concept of the deposition and diagenetic integrated phase for the first time, and influence of original decomposition and post-stage diagenesis on reservoir physical properties and logging response are taken into consideration; the classification standard of the diagenetic phase in the deposition and diagenetic integrated phase is re-defined, the principle of classifying the diagenetic phase according to the absolute values of compacting, cementing and corroding effects to the reservoir physical properties is provided for the first time, and thus, classification of the diagenetic phase is more accurate; and the logging identification method, in which crossplot identification is carried out on the basis of Bayesian discrimination, of the deposition and diagenetic integrated phase is provided for the first time, and the correct rate of logging identification is obviously improved.