Fig 1.
The workflow of the experimental study.
Table 1.
Mineral compositions and organic content of the marine shale samples used in this study.
Fig 2.
Schematic of the microwave oven used for investigating the pore structure of samples under electromagnetic radiation.
Fig 3.
Experimental apparatus for (a) low-pressure nitrogen adsorption and (b) FE-SEM characterization.
Fig 4.
Temperature profiles and temperature-changing rates of shale samples at different electromagnetic radiation times.
Fig 5.
The adsorption/desorption isotherms of shale samples at different electromagnetic radiation times.
Fig 6.
Comparison of the isothermals and pore-size distribution of samples #5–7.
Table 2.
The calculated AARDs of temperature, adsorption/desorption volume, pore-size distribution, and porosity between sample #5 and samples #6–7.
Table 3.
Pore volume, specific surface area, and types of isotherms of marine shale samples obtained at different electromagnetic radiation time.
Fig 7.
Pore-size distributions of marine shale samples obtained at different electromagnetic radiation times.
Fig 8.
The variation of porosity of marine shale samples at different electromagnetic radiation times.
Fig 9.
The SEM images obtained before and after 5 min of electromagnetic radiation.
In these figures, the organic pores/fractures are highlighted in circles.
Fig 10.
The SEM images showing the morphology and generated micro-fractures obtained before and after 5 min of electromagnetic radiation.
Fig 11.
Relationships between Ln(V) and Ln(Ln(P0/P)) fitted by the FHH model for marine shale samples at different electromagnetic radiation times.
In these figures, the blue ones are used to calculate the fractal dimension D1, while the red ones are applied to calculate the fractal dimension D2.
Fig 12.
Variations in the fractal dimension of D1 and D2 for marine shale samples at different electromagnetic radiation time.