Geology Reference
In-Depth Information
A
B
Gas and steam
Fire along vertical joints in coal
Coal pillar
Tipped overburden & waste
C
Figure 5.1.7. (A) Pillar failure caused by the spontaneous combustion of support pillars in an opencast coal mine.
(B) Burning-coal pillars causing the failure of tipped material. (C) Smoldering and burning coal carried by local
villagers, Singrauli coalfield, India. Photo A reproduced with permission of Taylor & Francis. Photo by Donnelly
2000.
Table 5.1.1
Examples of slope failures induced by spontaneous combustion, at an Indian
Opencast Coal Mine, Singrauli coalfield. Reproduced with permission of Taylor & Francis.
Date of failure
Description of events
October 3, 1997 The total preslide tip height was 106m and the overall slope was 48°, steepening to 76° in
the lower 50 m of the slope. Failure affected the dragline tip 50m high and 220m long. The
collapsed material accumulated on the floor of the mine where the Turra seam was being
extracted. The coal pillar underwent translational shift by 7 m toward the high wall face.
February 10, 1997 A slope failure affected the lower section of the steepest part of the dragline tips, to a height
of 48m. The total height of the tip before failure was 83m and was inclined at 54°. The
rotational slide was 140m wide and the coal underwent translational shift by 5m along the
floor of the seam, in the dip direction. The collapsed material accumulated up to 15m in the
mined out section of the workings.
May 28, 1997 A slope failure on, affected the lower 52m of the tipped material. The total height of the tip
before failure was 82 m and was inclined at 51°. The width of the slide was 51m, and the
tip material accumulated 18m into the workings.
September 19, 1998 A slope failure involved the failure of a 94m high, 47°, dragline tip. This created a scar
75 m high and 250 m long and caused the down-dip translational shift of the coal pillar by
65 m, stoping just short of the high wall.
Source:
Bell and Donnelly (2002, 2006).
