Institut za rudarstvo i metalurgiju Bor

exploitation, two variants of this method
of mining were developed as well as:
- the classic Aleksinac mining method,
and
- the changed or modified Aleksinac
method
The closure of the mine, occurred after
the large collective accident in 1989, the
coal exploitation was done in the north
area of ''Morava'' field, where the roompillar
mining methods were applied, so
called the Aleksinac methods.
The Aleksinac deposit is divided by
mining works into three coal fields: the
"Logorište", "Morava" and "Dubrava"
(Fig. 1) and the reserves are specially determined
for each field.
Until now, the area of Aleksinac mines
in its surroundings drilled over 120 drillholes.
Most of these drillholes were drilled
in order to investigate the coal.
In determining the possibility of oil
shale exploitation, their characteristics
have to be taken into account. Thus, according
to the size and complexity of the
geological oil shale deposits divided into
three groups, with each group divided into
three subgroups depending on the thickness
of the layer and the content of kerogen.
In determining the quality of oil shale
reserves, exploring layers, must be done,
complex mapping of all exploratory drillholes,
determine the genetic type of oil
shale and in particular, to determine the
qualitative and technological characteristics.
Requirements are set in definition of
oil shale contributed, to exist very few
established reserves and resources, while
the far greater share of potential reserves.
According to the structural material, the
Aleksinac deposit has a syncline form, in
most of the deposits and complex structure
in the "Dubrava", and is divided into
several thrust faults, major, independent
blocks. Layers are horizontal, slightly
sloping angle to 20 o and sink to 90 o , and
the deposit belong to second group. The
thick consistency and quality, of overlie
oil shale, there are classified into the subgroup
I. The floor oil shale, due to the
increased thickness variability and quality
were classified in the subgroup II. [11]
No 1, 2010. 49
MINING ENGINEERING