摘要:
A method for seismic characterization of subsurface Earth formations includes determining at least one of compressional velocity and shear velocity, and determining reservoir parameters of subsurface Earth formations, at least including density, from data obtained from a wellbore penetrating the formations. A quality factor for the subsurface formations is calculated from the velocity, the density and the water saturation. A synthetic seismogram is calculated from the calculated quality factor and from the velocity and density. The synthetic seismogram is compared to a seismic survey made in the vicinity of the wellbore. At least one parameter is adjusted. The synthetic seismogram is recalculated using the adjusted parameter, and the adjusting, recalculating and comparing are repeated until a difference between the synthetic seismogram and the seismic survey falls below a selected threshold.
摘要:
A method for seismic characterization of subsurface Earth formations includes determining at least one of compressional velocity and shear velocity, and determining reservoir parameters of subsurface Earth formations, at least including density, from data obtained from a wellbore penetrating the formations. A quality factor for the subsurface formations is calculated from the velocity, the density and the water saturation. A synthetic seismogram is calculated from the calculated quality factor and from the velocity and density. The synthetic seismogram is compared to a seismic survey made in the vicinity of the wellbore. At least one parameter is adjusted. The synthetic seismogram is recalculated using the adjusted parameter, and the adjusting, recalculating and comparing are repeated until a difference between the synthetic seismogram and the seismic survey falls below a selected threshold.
摘要:
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.
摘要:
A method for estimating a relationship between physical properties of a porous material from a sample thereof includes making a three dimensional tomographic image of the sample of the material. The image is segmented into pixels each representing pore space or rock grains. The image is divided into sub-volumes. A porosity is estimated for each sub-volume. At least one petrophysical parameter is modeled from the image of each sub-volume. A relationship between the porosity and the at least one modeled petrophysical parameter is determined by, e.g., a best-fit statistical method. The relationship and the modeled petrophysical parameter for each sub-volume are stored in a computer or displayed.
摘要:
The present invention relates to a method and system for integrating logging tool data and digital rock physics to estimate rock formation properties. A rock sample from a logging tool such as a sidewall plug or large enough cutting can be extracted by the logging tool at approximately the same well bore location that the logging tool measures fluid properties. The rock samples thus obtained is scanned using a CT scanner, scanning electron microscope or other suitable scanning device. The resulting scanned rock image can be segmented and rock properties comprising porosity, absolute permeability, relative permeability, capillary pressure and other relevant rock properties are calculated. The resulting digital calculations are integrated with logging tool data and rock property estimates to improve the accuracy and timeliness of the logging tool data.
摘要:
A method for estimating at least one elastic-wave-related property of a porous material from a sample thereof includes making a three dimensional tomographic image of the sample of the material. The image is segmented into pixels each representing pore space or rock grain. Bulk modulus and shear modulus of the porous material are determined from the segmented image at a frequency corresponding to mobile fluid. Bulk modulus and shear modulus of the porous material are determined from the segmented image at a frequency corresponding to immobile fluid. The at least one elastic-wave-related property is determined from the mobile fluid and immobile fluid moduli. The method includes at least one of storing and displaying the at least one elastic-wave-related property so determined.
摘要:
A method for estimating permeability properties of a porous material from a sample thereof includes making a three dimensional tomographic image of the sample of the material. The image is segmented into pixels each representing pore space or rock grains. The image is divided into sub-volumes. A porosity is estimated for each sub-volume. The components of a permeability tensor are determined by conducting simulations. Principal permeability values and directions are then calculated. The permeability properties are stored in a computer or displayed.
摘要:
A method for estimating permeability properties of a porous material from a sample thereof includes making a three dimensional tomographic image of the sample of the material. The image is segmented into pixels each representing pore space or rock grains. The image is divided into sub-volumes. A porosity is estimated for each sub-volume. The components of a permeability tensor are determined by conducting simulations. Principal permeability values and directions are then calculated. The permeability properties are stored in a computer or displayed.
摘要:
A method for determining in-situ relationships between physical properties of a porous medium from a sample thereof includes acquiring a three-dimensional image of the sample and segmenting the image into pixels representing pore space and pixels representing rock grain. A plurality of sub-volumes are selected from the segmented image, and a porosity is calculated for each of the sub-volumes. A digital simulation is conducted on each of the sub-volumes to obtain a selected physical property for the sub-volume. A relationship is determined between porosity and the selected physical property using relationship data comprising the calculated porosity and the simulated physical property for each of the sub-volumes. The method includes at least one of storing and displaying the relationship.
摘要:
A method for estimating a petrophysical parameter from a rock sample includes making a three dimensional tomographic image of the sample of the material. The image is segmented into pixels each representing pore space or rock grain. Porosity of the sample is determined from the segmented image. An image of at least one fracture is introduced into the segmented image to generate a fractured image. The porosity of the fractured image is determined. At least one petrophysical parameter related to the pore-space geometry is estimated from the fractured image.