Evaluation method for hydrogen containing ingredient, porosity and aperture of shale rich in organic matters

Abstract

The invention belongs to the technical field of oil and gas development, and discloses an evaluation method for hydrogen containing ingredient, porosity and aperture of shale rich in organic matters.According to the magnetic resonance imaging T1-T2 spectrum differences of kerogen, kerogen containing adsorption oil, different minerals containing aqueous clay, shale, shale dry samples, saturated oil rock samples and saturated water rock samples, a division scheme of each hydrogen containing ingredient of the shale rich in organic matters, and a quantitative expression method of fluid ingredients is established; the T2 spectrum of the saturated shale rich in organic matters is taken as a target, the T2 spectrum of the shale dry sample is taken as a substrate, substrate inversion is carried out to obtain the T2 spectrum of oil in a hole, and on the basis of the T2 spectrum, the porosity and the pore diameter distribution of the shale rich in organic matters is evaluated. Compared with theconventional method, the evaluation method disclosed by the invention is characterized in that high innovation and credibility can be shown, and is favorable for improving the analysis of the magnetic resonance imaging on an aspect of shale rock physical measurement.

Description

technical field [0001] The invention belongs to the technical field of oil and gas development, and in particular relates to an evaluation method for hydrogen-containing components, porosity and pore diameter of organic-rich mud shale. Background technique [0002] At present, the existing technologies commonly used in the industry are as follows: [0003] Shale oil and gas refers to hydrocarbons that have been generated but remain in the micro-nano pores of shale formations. In recent years, they have attracted extensive attention because of their huge resources. Shale oil in shale (TOC>2%) formations is the primary research object of economic recovery. Compared with conventional sandstone reservoirs, organic matter-rich shale has the characteristics of complex hydrogen-containing components (high clay minerals, rich in organic matter), compactness (low porosity and low permeability), etc. There are limitations in the identification of hydrogen-containing components i...

AI Technical Summary

Problems solved by technology

[0005] (1) The main problems of the signal-shielding method and the two-dimensional NMR method are: ①When manganese chloride or heavy water cannot enter small pores or dead pores, the water signal may not be shielded; ②Lacustrine mud shale is rich in Clay minerals, Mn2+ will hydrolyze with some clay minerals to destroy the pore structure (Wang et al., 2003); ③This method only separates the oil-water signal, but cannot distinguish the signal of kerogen

[0007] (2) The test results of the helium method porosity are optimized for the test parameters of the NMR experiment. The phenomenon of hydration and expansion (Liang et al., 2015) destroys the original pore structure characteristics of shale, resulting in the distortion of the porosity and pore size distribution of the NMR test; Under this TE test condition, although the porosity value of the NMR test is equal to that of the helium method, in theory, the test results lose part of the nanopores with a shorter relaxation time. ③ The organic-rich shale has a high content of organic matter, and the NMR T2 spectrum directly tested on the fluid-saturated rock sample contains more solid organic matter and mineral structure water signal, this part of the signal is not the fluid component in the pores, and cannot be used to directly calculate the porosity and pore size distribution

[0015] Compared with conventional sandstone reservoirs, organic-rich shale has developed micro-nano pores, contains a large number of organic matter / mineral structure water signals, and the fluid in micro-nano pores is closer to the NMR relaxation characteristics of organic matter / mineral structure water. This undoubtedly increases the difficulty of nuclear magnetic resonance technology in the detection of fluid signals in micropores and the interpretation of hydrogen signals, which leads to the inadequacy of the identification of hydrogen-containing components and the evaluation of porosity and pore size distribution. Evaluation Method of Shale Containing Organic Matter

Images