Study on the pore structure and fractal characteristics of marine and continental shale based on mercury porosimetry, N2 adsorption and NMR methods

In this study, a series of nuclear magnetic resonance (NMR) tests was conducted on calcareous sand, quartz sand, and glass bead with a wide range of grain sizes, to understand the effect of grain size on the micro-pore structure and fractal characteristics of the carbonate-based sand and silicate-based sand. The pore size distribution (PSD) of the tested materials were obtained from the NMR T2 spectra, and fractal theory was introduced to describe the fractal properties of PSD. Results demonstrate that grain size has a significant effect on the PSD of carbonate-based sand and silicate-based sand. As grain size increases, the PSD of sands evolves from a binary structure with two peaks to a ternary structure with three peaks. The increase in the grain size can cause a remarkable increase in the maximum pore size. It is also found that the more irregular the particle shape, the better the continuity between the large and medium pores. In addition, grain size has a considerable effect on the fractal dimension of the micro-pore structure. The increase of grain size can lead to a significant increase in the heterogeneity and fractal dimension in PSD for calcareous sand, quartz sand and glass bead.

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Effect of ZnCl2 impregnation ratio on pore structure of activated carbons prepared from cattle manure compost: application of N2 adsorption-desorption isotherms

Journal of Material Cycles and Waste Management ◽

10.1007/s10163-007-0185-x ◽

2008 ◽

Vol 10 (1) ◽

pp. 53-61 ◽

Cited By ~ 11

Author(s):

Qingrong Qian ◽

Motoi Machida ◽

Masami Aikawa ◽

Hideki Tatsumoto

Keyword(s):

Pore Structure ◽

Activated Carbons ◽

Cattle Manure ◽

N2 Adsorption ◽

Manure Compost ◽

Impregnation Ratio ◽

Compost Application ◽

Desorption Isotherms ◽

Cattle Manure Compost ◽

Adsorption Desorption

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Fractal Characteristics of the Pore Network in Diatomites Using Mercury Porosimetry and Image Analysis

Springer Proceedings in Physics - 2nd International Multidisciplinary Microscopy and Microanalysis Congress ◽

10.1007/978-3-319-16919-4_11 ◽

2015 ◽

pp. 79-89

Author(s):

Grażyna Stańczak ◽

Marek Rembiś ◽

Beata Figarska-Warchoł ◽

Tomasz Toboła

Keyword(s):

Image Analysis ◽

Mercury Porosimetry ◽

Pore Network ◽

Fractal Characteristics

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Multifractal Analysis of Pore Structure in Middle- and High-Rank Coal by Mercury Intrusion Porosimetry and Low-Pressure N2 Adsorption

Natural Resources Research ◽

10.1007/s11053-021-09952-z ◽

2021 ◽

Author(s):

Shasha Zhang ◽

Huan Liu ◽

Zhehui Jin ◽

Caifang Wu

Keyword(s):

Pore Structure ◽

Multifractal Analysis ◽

Mercury Intrusion Porosimetry ◽

Low Pressure ◽

High Rank ◽

N2 Adsorption ◽

Mercury Intrusion

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Comparative analysis of pore structure and fractal characteristics of micropores in medium and high rank coals——Taking the typical mining area of western Guizhou and eastern Yunnan as an example

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/332/2/022015 ◽

2019 ◽

Vol 332 (2) ◽

pp. 022015

Author(s):

Yujie Peng ◽

Guoneng Chen ◽

Peng Liu ◽

Xili Qi ◽

Shuai Song

Keyword(s):

Comparative Analysis ◽

Pore Structure ◽

Mining Area ◽

High Rank ◽

Fractal Characteristics ◽

Western Guizhou

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Experimental analysis of the pore structure and fractal characteristics of different metamorphic coal based on mercury intrusion‑nitrogen adsorption porosimetry

Powder Technology ◽

10.1016/j.powtec.2019.11.092 ◽

2020 ◽

Vol 362 ◽

pp. 386-398 ◽

Cited By ~ 40

Author(s):

Weibo Han ◽

Gang Zhou ◽

Danhong Gao ◽

Zhixue Zhang ◽

Zunyi Wei ◽

...

Keyword(s):

Pore Structure ◽

Experimental Analysis ◽

Nitrogen Adsorption ◽

Mercury Intrusion ◽

Fractal Characteristics

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The Impacts of Matrix Compositions on Nanopore Structure and Fractal Characteristics of Lacustrine Shales from the Changling Fault Depression, Songliao Basin, China

Minerals ◽

10.3390/min9020127 ◽

2019 ◽

Vol 9 (2) ◽

pp. 127 ◽

Cited By ~ 6

Author(s):

Zhuo Li ◽

Zhikai Liang ◽

Zhenxue Jiang ◽

Fenglin Gao ◽

Yinghan Zhang ◽

...

Keyword(s):

Fractal Dimension ◽

Pore Structure ◽

Fractal Dimensions ◽

Organic Medium ◽

Songliao Basin ◽

Sem Images ◽

Fractal Characteristics ◽

Inorganic Mineral ◽

Nanopore Structure ◽

High Fractal Dimension

The Lower Cretaceous Shahezi shales are the targets for lacustrine shale gas exploration in Changling Fault Depression (CFD), Southern Songliao Basin. In this study, the Shahezi shales were investigated to further understand the impacts of rock compositions, including organic matters and minerals on pore structure and fractal characteristics. An integrated experiment procedure, including total organic carbon (TOC) content, X-ray diffraction (XRD), field emission-scanning electron microscope (FE-SEM), low pressure nitrogen physisorption (LPNP), and mercury intrusion capillary pressure (MICP), was conducted. Seven lithofacies can be identified according to on a mineralogy-based classification scheme for shales. Inorganic mineral hosted pores are the most abundant pore type, while relatively few organic matter (OM) pores are observed in FE-SEM images of the Shahezi shales. Multimodal pore size distribution characteristics were shown in pore width ranges of 0.5–0.9 nm, 3–6 nm, and 10–40 nm. The primary controlling factors for pore structure in Shahezi shales are clay minerals rather than OM. Organic-medium mixed shale (OMMS) has the highest total pore volumes (0.0353 mL/g), followed by organic-rich mixed shale (ORMS) (0.02369 mL/g), while the organic-poor shale (OPS) has the lowest pore volumes of 0.0122 mL/g. Fractal dimensions D1 and D2 (at relative pressures of 0–0.5 and 0.5–1 of LPNP isotherms) were obtained using the Frenkel–Halsey–Hill (FHH) method, with D1 ranging from 2.0336 to 2.5957, and D2 between 2.5779 and 2.8821. Fractal dimensions are associated with specific lithofacies, because each lithofacies has a distinctive composition. Organic-medium argillaceous shale (OMAS), rich in clay, have comparatively high fractal dimension D1. In addition, organic-medium argillaceous shale (ORAS), rich in TOC, have comparatively high fractal dimension D2. OPS shale contains more siliceous and less TOC, with the lowest D1 and D2. Factor analysis indicates that clay contents is the most significant factor controlling the fractal dimensions of the lacustrine Shahezi shale.

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