A Saturation Determination Method Based on Multispectral Pore Structure Analysis

Abstract

The invention discloses a multispectral pore structural analysis-based saturation determining method which comprises the following steps of: carrying out micro CT (Computer Tomography) scanning and imaging on a rock core of a typical rock sample; quantitatively extracting a pore radius distribution spectrum of the typical sample in a three-dimensional space; acquiring the pore structure characteristic of the typical rock sample according to a nuclear-magnetism T-2 spectrum of the typical rock sample; generating a porosity distribution spectrum of the typical rock sample according to electric imaging log data of the typical rock sample; jointly determining the pore structure type of the typical rock sample according to the pore radius distribution spectrum, the nuclear-magnetism T-2 spectrum and the electric imaging porosity distribution spectrum; and determining a saturation model corresponding to the typical rock sample according to the pore structure type of the typical rock sample and determining the saturation of an oil-gas storage and collection layer in which the typical rock sample is positioned according to the saturation model.

Description

technical field [0001] Aiming at complex reservoirs such as volcanic rock, carbonate rock, and low-porosity and low-permeability clastic rock, the present invention proposes a method for determining saturation based on multispectral pore structure analysis. Background technique [0002] Quantitative calculation of formation oil saturation is the basic task of logging interpretation and evaluation, and it is also the core of quantitative evaluation of oil and gas reservoirs. At present, the saturation evaluation based on resistivity is still the most used in logging interpretation. Although other logging techniques such as nuclear magnetic resonance and array induction can also provide information related to reservoir saturation, they are limited by these logging techniques. The cost, multi-solution, applicability and other conditions of the application of well technology are limited, and the actual application in the oil field is seldom. [0003] The core of oil and gas sat...

AI Technical Summary

Problems solved by technology

However, with the deepening of research, more core experiments of volcanic rock reservoirs have been completed. After in-depth analysis, it is found that even if the lithology is the same, the relationship between porosity and electrical properties is not unique. The essence lies in the pore structure type of the rock, so the application of the saturation calculation method centered on porosity in heterogeneous and complex reservoirs also has limitations

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