Ground subsidence in mining occurs when underground material movement causes the ground above mines to sink or subside. It is mostly caused by the removal of resources during mining operations. Subsidence can damage infrastructure and the environment on the surface and underground. To monitor and prevent subsidence, mining surveys use techniques like synthetic aperture radar interferometry, GPS, precise leveling, and electronic distance measurement to track ground movement. These surveys provide data to support ground stability and safe mining operations while minimizing negative impacts.

1. Deformation due to ground
subsidence in Mining
.
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2. 2.1 Background
 Movement in materials underground, dislocation in rocks leads to land
deformation.
 It is mostly caused by removal of mineral resources out of the ground by
pumping and drilling.
 It can also occur due to natural events such as earthquakes.
 All these events may collapse the hanging wall due to additional stress in the
rocks and change is surface topography.
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3. What is subsidence ?
the gradual caving in or sinking of an area or land
Ground Subsidence :
it is the sinking of the ground because of underground
material movement
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4. 2.2 Elements of subsidence syncline
 Subsidence is mainly seen in room and pillar mines.
 When the roof of subsurface mine collapse it causes the ground
above to sink or subside.
 Technically it means lateral or vertical ground movement caused by
a failure initiated at the mine level, of man-made underground
mines, including coal mines, limestone mines and fluorspar mines
that directly damages residence or commercial buildings.
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5. Elements of subsidence syncline cont.
Mine subsidence does not include lateral or vertical ground
movement cause by earth shake, landslide, volcanic eruption, soil
conditions, soil erosion, soil freezing and thawing, improperly
compacted soil, construction defects, roots of trees shrubs or collapse
of trees oand shrubs or collapse of storm and sewer drains and rapid
transit tunnels.
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6. 2.3 Mine surveying methods used to
monitor ground subsidence
This refers to applicable and applied surveying techniques in mining
operations/environments to provide accurate and important
quantitative data regarding the behaviour of surrounding rock/ground,
performance of the ground support systems, safety and stability of the
underground mining work and the excavation progress.
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7. 2.4 Mine surveying methods used to
monitor ground subsidence
Methods include:
1. Synthetic aperture radar interferometry
2. Global Positioning System(GPS)
3. Conventional precise levelling and theodolite
4. Remote electronic monitoring
5. Electronic Distance Measurement (EDM) Surveys
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8. 2.4 Mining damages on the surface
1. Damage to land resources
 Mining destroys beneficial micro organisms in topsoil
 Soil may be damaged if reclamation operations mix with subsoils
 Mining may damage lands in ways that prevent a return to previous land use e.g
farming
 Erosion may increase dramatically once natural vegetation is removed
2. Water Resource Management
 Irresponsible surface mining can pollute streams and disrupt water supplies
 Water pollution from discharged mine effluent and seepage from tailings and waste
rock impoundments
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9. 2.4 Mining damages on the surface cont.
3. Wildlife damage
 All species are either destroyed or displaced from the area of mine itself
 impairment of habitats of aminal species
 Heavy metals and compounds that can alter the ph of soil are exposed and leach into
streems’
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10. 2.5 Mining damages underground
➢ Mines collapse and buildings start to crack
➢ Disruption of underground water flow i.e aquifers
➢ Stability of pipelines and drains is affected
➢ Tilts i.e change in slope of land surface
➢ Failure of well casings
➢ Underground railways are damaged
➢ Changes in elevation and slope of streams, canals and drains.
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11. 2.6 Conclusion
Mining damages on the surface and underground may be quiet severe
on wildlife, land resources, water resources management and
underground facilities. To avoid these damages mining surveying has
employed different monitoring methods e.g. GPS
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12. References
Retrieved from:
https://www.researchgate.net/publication/2836108_Mining_Subsidence_Monitoring
Retrieved from https://www.science.gov/topicpages/m/mining+subsidence+monitoring.html
Hu, H.; Lian, X.G.; Cai, Y.F.; Zhang, K. Study on ecological environment damage and restoration
for coal mining—subsided area in loess hilly area of Shanxi Province. Coal Sci. Technol. 2020, 48,
70–79
Dai, H.Y.; Guo, J.T.; Yan, Y.G. Principle and application of subsidence control technology of mining
coordinately mixed with backfilling and keeping. J. China Coal Soc. 2014, 39, 1602–1610
Helmut Kratzsch. (1993) Mining Subsidence Engineering ISBN-13 :978-3-642-81925-4
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