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Modelling of P-wave velocity changes in coal seams with increased depth: a case study
Maciej Łapczyński1, Zenon Pilecki2, Krzysztof Krawiec1
1Mineral and Energy Economy Research Institute of the Polish Academy of Sciences, Wybickiego 7A, 31-261, Kraków, Poland.
Scientific Reports
|January 27, 2025
Summary
This study refines P-wave velocity calculations for coal seams at greater depths, improving seismic hazard assessments and coal exploitation. The updated formula enhances accuracy in geomechanical condition analysis for deep mining operations.
Area of Science:
- Geophysics
- Mining Engineering
- Seismology
Background:
- Seismic profiling detects P-wave velocity anomalies in coal seams, indicating stress changes relevant to mining safety.
- Accurate reference P-wave velocity is crucial for interpreting these anomalies, especially at increasing mining depths.
Purpose of the Study:
- To update the empirical formula for calculating reference P-wave velocities in coal seams.
- To incorporate new velocity data from greater depths to improve accuracy.
Main Methods:
- Collected 276 P-wave velocity values, including 24 new measurements from 704-1073m depth.
- Applied regression analysis to modify the standard velocity calculation model.
- Conducted research at Zofiówka Coal Mine, Poland.
Main Results:
- Developed a modified mathematical model for reference P-wave velocities.
- The new model offers more reliable velocity anomaly calculations.
- The updated model accurately reflects geomechanical conditions at greater depths.
Conclusions:
- The enhanced formula improves the assessment of geomechanical conditions in deep coal seams.
- This methodology supports safer and more efficient coal exploitation in seismically active areas.
- The procedure is adaptable for various underground mining conditions with increasing depths.
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