SY/T 7410.2-2020 in English

Standard Technical Background

SY/T 7410.2-2020, as the core standard of the oil and gas industry, proposes a nanoscale observation scheme using a focused ion beam scanning electron microscope (FIB-SEM) to address the resolution limitations of traditional CT scanning methods (micrometer level). This technology can achieve continuous imaging with a slice interval of 5-50nm, providing technical support for the study of unconventional reservoirs such as shale gas.

Key equipment requirements

Sample preparation specifications

3D reconstruction process

1. Image acquisition: 500 continuous slices, 30nm interval
2. Grayscale correction: Eliminate background differences in the Y direction
3. Threshold segmentation: Use Otsu algorithm to determine pore boundaries
4. Parameter calculation: Porosity error ≤0.5%

Quality factor control

• Image clarity: Mineral-pore boundaries are discernible
• Data integrity: Contains XYZ three-dimensional permeability
• Report specifications: 12 parameters such as acceleration voltage must be indicated

Technology evolution comparison

Compared with the 2015 draft, the 2020 version adds:
1) Carbon fiber conductive treatment scheme
2) Backscattered electron image resolution index
3) Confidence interval requirements for crack width statistics