Projects / Programmes
Vpliv strukture na varnost odkopavanja debelih slojev premoga - dejavniki tveganja in njihovo obvladovanje (Slovene)
| Code |
Science |
Field |
Subfield |
| 2.16.03 |
Engineering sciences and technologies |
Mining and geotechnology |
Geotechnology |
| Code |
Science |
Field |
| 2.07 |
Engineering and Technology |
Environmental engineering
|
Researchers (7)
Organisations (2)
Significance for science
In the frame of the project we created a structural model of the production area in the Velenje basin, which is based on structural mapping of fault zones and their characteristics. We documented 3D mezoscopic-scale geometry of fault structures, temporal evolution of the fault network, and history of slip episodes on fault planes.
We determined the characteristics of faults and fault zones in lignite, and documented various manifestations of tectonically deformed coal in fault zones. We investigated the influence of those tectonic features on mechanical properties and gas behavior in coal. These findings improve the forecasting of structural and mechanical conditions in developing mine works.
We demonstrated a significant correlation between the location of fault zones and the appearance of hazardous geodynamical events. Therefore, the tectonic structure is a major risk factor in coal mining. We showed that the induced stress fields in the coal seam that are generated during excavation may activate slip on fault planes, which produces seismic events. The induced stress fields furthermore enhance the primary (tectonic) fracturation of the coal and thus increase their mechanical weakness and potential for gas outbursts. Therefore, even minor faults and mine areas with minor tectonic deformation may be subject to structurally-controlled risk. We show that continuous and systematic in-situ structural mapping of mine works is the most appropriate and cost-effective method for monitoring structure in areas of minor tectonic deformation.
By mapping inside the mine we obtained data which are normally not available with classical methods of investigation, like surface geological mapping, drilling, and geophysical prospection. Our observations and structural interpretation are therefore an important contribution to knowledge in the field of structural geology and tectonics, since they offer a direct insight into mechanisms of tectonic deformation in strike-slip basins, and allow testing of various existing models of their evolution. Such models have a significant practical value, since strike-slip basins are an important source of mineral deposits and petroleum worldwide.
We developed and put into operation a strategy for mapping and forecasting the structurally-controlled risk, which can be applied in other coal mines with thick or steeply-dipping coal seams. Our approach is based on continuous systematic structural mapping of mine works and the transfer of the mapping data into spatially-referenced database. The degree of structurally-controlled risk is then determined in a GIS application by taking into account the local geological conditions. This approach provides, in near-real-time, the support for mine design and the planning of safety measures during excavation.
Significance for the country
The Republic of Slovenia is planning to utilize the lignite from the Velenje Coal Mine for at least the next 35 years. The coal from Velenje provides source for one third of the electrical power consumed in the country. Mining of coal in Velenje is therefore of strategic importance, particularly during periods of low rainfall (when hydroelectric power plants are disabled) and in the times of maintenance of the Krško nuclear power plant. The results of the proposed project, particularly the contribution to hazard mitigation, will contribute to stable and uninterrupted production of coal, as each spontaneous geodynamic event and its consequences can hinder production for a considerable period of time. The results of the project will optimize the application of safety measures and will thus contribute to reduction in costs of operation.
The results of the project and the acquired knowledge will be useful in projects of reducing emissions of greenhouse gases, to which the Republic of Slovenia and the European Union are committed. The knowledge of geological structure of the basin, and of sorptional and mechanical properties of faults and fault zones in the coal seam plays an important role in planning clean coal technologies (degassing of the coal seam before and during the excavation) and in planning carbon capture and sequestration in the coal seam. Initial activities for both projects are already in progress.
Acquired knowledge will also be useful for planning the utilization of strategic reserves of coal in NE Slovenia, which will require underground coal gasification.
Most important scientific results
Annual report
2011,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2010,
final report,
complete report on dLib.si
