5
IMPLEMENTATION OF VIDEO
BORESCOPES AT MINING OPERATIONS
The video produced at one borehole underground can pro-
vide very specific information about the roof rockmass in
one location. Some features that can be seen are cracks in
the strata, horizontal shifts, changes in lithology, observing
glue migration, methane, slicks, and changes in bedding
thickness (see Figure 4). During the observations, notes
should be taken to describe the type of lithology, the thick-
ness of bedding planes, any inclusions (coal streaks, sand-
stone or shale streaks, clay, etc.), and the overall thickness of
the rock unit. These descriptions will assist geomechanical
engineers in understanding the strength of the rockmass in
the roof of the mine and implement better support plans to
reduce roof falls.
Figure 3. Three images from video borescopes in a 1-inch diameter hole: (A) is a picture of sandstone from a lower-cost
borescope with a focal point of 1.2 inches (B) is a picture of broken sandstone from a lower-cost borescope with a focal point
less than an inch (C) is a picture of a contact between sandstone and shale from a higher-cost borescope with a focal point of
less than one inch.
(a) (b) (c)
Figure 4. Videoscope images of (from the left) a horizontal shift, laminated strata, crack in sandstone, and glue migration.
All of these images were taken with a low-cost videoscope
IMPLEMENTATION OF VIDEO
BORESCOPES AT MINING OPERATIONS
The video produced at one borehole underground can pro-
vide very specific information about the roof rockmass in
one location. Some features that can be seen are cracks in
the strata, horizontal shifts, changes in lithology, observing
glue migration, methane, slicks, and changes in bedding
thickness (see Figure 4). During the observations, notes
should be taken to describe the type of lithology, the thick-
ness of bedding planes, any inclusions (coal streaks, sand-
stone or shale streaks, clay, etc.), and the overall thickness of
the rock unit. These descriptions will assist geomechanical
engineers in understanding the strength of the rockmass in
the roof of the mine and implement better support plans to
reduce roof falls.
Figure 3. Three images from video borescopes in a 1-inch diameter hole: (A) is a picture of sandstone from a lower-cost
borescope with a focal point of 1.2 inches (B) is a picture of broken sandstone from a lower-cost borescope with a focal point
less than an inch (C) is a picture of a contact between sandstone and shale from a higher-cost borescope with a focal point of
less than one inch.
(a) (b) (c)
Figure 4. Videoscope images of (from the left) a horizontal shift, laminated strata, crack in sandstone, and glue migration.
All of these images were taken with a low-cost videoscope