Reconstruction of Pore-space Images Using Microtomography and Multiple-point Statistics
نویسندگان
چکیده
Quantitative prediction of petrophysical properties for reservoir rocks frequently employs representative microscopic models of the pore space as input. Recently digital imaging techniques such as microtomography have been used to provide void space images at the resolution of a few microns. However, this resolution may be insufficient to capture some smaller structures, particularly in carbonates. An emerging destructive focused ion beam method can provide better resolution but only on very small samples. Two-dimensional (2D) thin sections, in contrast, are easily available and they can image micro-porosity. However, they do not directly capture the three-dimensional (3D) pore space. We propose an integrated approach to combine different types of image to reconstruct porous media. In order to generate geologically realistic pore space images with appropriate connectivity, particularly for carbonate rocks, relatively low resolution microtomography and higher resolution images from thin-sections are used. 2D thin-sections provide multiple-point statistics (MPS), which describe the statistical relation between multiple spatial locations and their statistics can be used to generate 3D images at higher resolution. The reconstruction using multiple-point statistics allows the connectivity of the void space to be reproduced accurately. The statistically reconstructed images are then combined with the images measured by the microtomography to generate a realistic pore structure since some 2D thin-sections may miss macro-porosity due to their size. The integrated method is tested on carbonates for which 3D images of larger vug porosity are captured, while 2D thin sections accurately characterize small-scale structure. The integrated images have permeabilities computed using the latticeBoltzmann method (LBM) that are similar to laboratory-measured values, which indicates that the proposed method is both practical and realistic.
منابع مشابه
Pore space reconstruction of vuggy carbonates using microtomography and multiple-point statistics
[1] To reconstruct complex porous media, such as carbonates, we propose a two-step approach to combine different types of images: microtomography at the resolution of a few microns to resolve large pores and vugs, with statistically reconstructed highresolution images for smaller features. Two-dimensional (2-D) thin sections provide multiple-point statistics which describe the statistical relat...
متن کاملPore space reconstruction using multiple-point statistics
The reconstruction of porous media is of great interest in a wide variety of fields, including earth science and engineering, biology, and medicine. To predict multiphase flow through geologically realistic porous media it is necessary to have a threedimensional (3D) representation of the pore space. Multiple-point statistics were used, based on two-dimensional (2D) thinsections as training ima...
متن کاملPredicting Permeability through 3d Pore-space Images Reconstructed Using Multiple-point Statistics
Pore-scale network modeling can predict multiphase flow properties with arbitrary wetting conditions if the network represents the geology of the sample accurately. Such pore-scale modeling uses topologically disordered networks that realistically represent the pore structure. To generate the network it is first necessary to have a three-dimensional voxel-based pore-space representation that is...
متن کاملSca2003-09: Multiple-point Statistics to Generate Geologically Realistic Pore-space Representations
The resolution of current micro-CT scanning –a few microns – means that for many rocks, significant porosity cannot be imaged directly in three dimensions. Furthermore, alternative approaches, such as reconstruction through simulating sedimentation and diagenesis, may be problematic for many materials whose depositional and diagenetic history is uncertain or complex. In these cases it is necess...
متن کاملPrediction of permeability for porous media reconstructed using multiple-point statistics.
To predict multiphase flow through geologically realistic porous media, it is necessary to have a three-dimensional (3D) representation of the pore space. We use multiple-point statistics based on two-dimensional (2D) thin sections as training images to generate geologically realistic 3D pore-space representations. Thin-section images can provide multiple-point statistics, which describe the st...
متن کامل