This document will provide information on two important topics of Mining. One is the different methods used in underground mining along with underground mine anatomy and other is the SWOT (Strength, Weakness, Opportunity and Threat) analysis of Maddhapara Granite, Parbatipur, Dinajpur, Bangladesh.

1. GS-502 Assignment
DEPARTMENT OF GEOLOGICAL SCIENCES
JAHANGIRNAGAR UNIVERSITY
SAVAR, DHAKA-1342
Mines & Minerals
SUBMITTED BY:
MD. SHAHADAT HOSSAIN
Roll No: 1651
Session: 2017-2018

2. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
1 | P a g e
1. Explain infrastructure of the underground mine and provide information on different stoping
methods in underground mining.
Underground mining:
The process of extracting ore or valuable minerals from the subsurface utilizing modern scientific
infrastructure and keeping the mine safe with as little waste as possible is called underground mining.
This process is more expensive, laborious, hazard prone than open cast mining but more productive than
the open casts. In order to catch hold of the subsurface ore, different types of shafts, adits and pathways
are constructed which are introduced below:
Adit: Horizontal or near horizontal entrance to a mine is called an adit.
Back: Roof or overhead surface of an underground excavation.
Chute: Arrangement for moving extracted materials from a higher level to a lower level making use of
gravity.
Crosscut: Horizontal or near horizontal underground opening driven to intersect an ore body.
Drawpoint: A place where ore can be loaded and removed.
Figure. 1: Infrastructure of an underground mine.

3. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
2 | P a g e
Drift: A horizontal passage underground that follow along the length of a vein or rock formation as
opposed to a crosscut which crosses the rock formation.
Footwall: Wall or rock under the ore deposit.
Grizzly: An arrangement that prevents oversized rocks from entering as ore transfer system.
Hanging wall: Wall or rock above an ore deposit.
Level: A level forms the basis for excavation of the ore above or below. It is the system of horizontal
underground workings connected to the shaft.
Manway: Openings that are used for personnel use.
Ore: Mineral deposit that can be extracted at profit.
Prospect: Mineral deposit for which the economic value has not been yet proven.
Raise: Underground opening that has been driven upward from a level below.
Ramp: Inclined underground openings that connect levels.
Shaft: Vertical or horizontal opening through which ore or men can get out/get in the mine.
Stope: Underground excavation made by removing ore from surrounding rock.
Wall rock: Wall in which an ore deposit is enclosed.
Waste: Uneconomic part of the ore.
Winze: Vertical or inclined underground opening driven downward from one level to another.
Different stoping methods in underground mining:
Various methods have been developed in order to extract ore from the subsurface. The methods mainly
depend on the ore that is needed to be extracted, surrounding geology, profit to invest ratio etc. Some of
the well known processes are described below:
Room and Pillar method:
This process is most suitable for flat bedded deposits with limited extent such as copper, coal, salt etc. In
this method ore is being extracted from rooms and the pillars are left behind to support the wall. The
pillars are designed such a way that maximum ore can be extracted giving full protection to the mine.
Pillars can be designed as circular, square or can be shaped as elongated walls separating the rooms. The
ore from the pillars are non-recoverable so this is excluded while calculating the reserve amount.
Maddhapara granite is extracted using this method.

4. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
3 | P a g e
Figure. 2: Room and Pillar method
Shrinkage Stoping:
In shrinkage stoping ore is excavated in horizontal slices, starting from the bottom of the stope and
advancing upward. Part of the broken ore is left in the mined-out stope where it serves as a working
platform for mining the ore above and to support the stope walls. Through blasting, rock increases its
occupied volume by about 50%. Therefore, 40% of the blasted ore must be drawn off continuously during
mining.
Shrinkage stoping can be used un ore bodies with
 Steep dips
 Firm ore
 Comparatively strong hanging and footwall
 Regular ore boundaries
 Ore that is not affected by storage in the stope
Figure. 3: Shrinkage Stoping

5. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
4 | P a g e
Cut and Fill Stoping:
Cut and fill mining removes ore in horizontal slices starting from the bottom undercut and advancing
upward. Ore is drilled and blasted and muck is loaded and removed from the site. When the stopes are
mined out, the voids are filled with waste rock. The fill supports both the support and the platform to
work on next stope. Cut and fill mining is used in steeply dipping ore bodies in strata having good to
moderate stability and high grade ore. Cut and fill allows selective mining, separate recovery of high
grade sections and leaving low grade rock behind the stopes.
Figure. 4: Cut and Fill Stoping method
Longwall Mining:
Longwall mining applies to thin bedded deposits of uniform thickness and large horizontal extent. Typical
targets are coal seams, potash layers. Longwall mining method targets both hard and soft rocks as the
mined area is supported artificially. This method can be mechanized almost to perfection. The soft
material does not require drilling and blasting but can be cut loose mechanically. Special machines shaped
as cutting plows or rotating drums with cutters run back and forth along the faces, each time cutting a
fresh slice of seam. The coal or mineral falls onto a conveyor belt that transports the ore.
Figure. 5: Longwall mining method

6. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
5 | P a g e
Underground Glory Hole:
Similar to surface glory hole comprising funnel shaped excavation from the footwall shaft. Crosscuts are
drawn to intersect the ore body and raises are made. The method is advantageous when working large ore
as well as rocks are strong. In this method, a deposit is divided by levels and on every level chutes are
raised to the next one. Mining starts from the mouth of the chutes in such a way as to develop a funnel
shaped excavation with slopes so steep that broken ore falls into the chutes and thus to the cars on the
lower level.
Figure. 6: Underground Glory Hole mining method
2. SWOT analysis with example on any mineral resources.
SWOT analysis is a brilliant philosophy to evaluate the Strength, Weakness, Opportunity and Threat of a
certain organization, project or business venture. The idea was developed at Stanford way back to 1970s
but still is as much as applicable to justify the expected outcome from project. SWOT analysis is a simple
but powerful framework for leveraging the organization's strengths, improving weaknesses, minimizing
threats, and taking the greatest possible advantage of opportunities. The SWOT analysis of Maddhapara
granite is discussed below in this literature:
About Maddhapara:
Maddhapara lies within the Rangpur Saddle between the flood plains of the Ganges to the west and
Brahmaputra to the east (Figure. 7) (Bakhtine 1966, Reimann 1993). The Rangpur Saddle has been
considered by some of the researchers as the northeastern continuation of the Indian Shield which may
extend up to the Shillong Massif and Mikir Hills further to the northeast (Reimann, 1993).
The main rock type identified in the boreholes of Maddhapara is Tonalite (Ameen et al. 2007, Ameen et
al. 1998, Kabir et al. 2001) with lesser amounts of Granodiorite and Monzogranite.

7. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
6 | P a g e
Figure. 7: Location of Madhhapara granite occurrence site after Ameen et al. 2007
Strength:
 Superior Engineering Quality
Parameter Value
High Compressive strength 24000 psi
Hardness 6.5
Specific gravity of the rock Average 2.7
Rock Quality Designation (RQD) 5%
Fracture Spacing Index (FSI) 0.1 to 2 per feet
Sulphate content 0.05%
(Source: Brochure of MGMCL)
 Economic Benefits
-The shallowest depth from the surface (128-154m) allows extraction at relatively cheap rate and
possible expansion of the mine when needed.
-Quality is better than any other indigenous or imported stone.
-Price is competitive compared to the imported stone.
-Savings of valuable foreign currencies.
-Bangladesh is one of those countries where cheap labor can be found.

8. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
7 | P a g e
Weakness:
 The main weakness still is the lack of qualified man power at MGMCL. Adequate researches
seem yet to be done after discovering the mine. As stated in the opportunity section, Maddhapara
still holds some further possible outcomes which can add to the revenue of MGMCL.
 Interrupted rock production due to machinery problems and political issues is beyond mention.
 Underground transport facility, rock blasting method, ventilation system cannot be appreciated at
all.
Figure. 8: Underground situation at Maddhhapara
Opportunity:
 Bangladesh requires 6 million ton hardrock per year for construction purposes. Only a small
portion of this demand is met by the gravels collected from different rivers and paleochannels at
the Himalayan foothills. In this backdrop, Maddhapara hardrock can have a great impact.
 Dependability for hardrock on other countries can be minimized.
 Igneous rocks are in general are the sources of all types of minerals. Granitoids dissected by late
pegmatite dykes, quartz/pyrite veins are generally considered to be promising for mineralization.
In Maddhhapara, diorite and granodioritic rocks are traversed by numerous quartz veins and
pegmaititc dykes. This can provide a new window for searching mineralized zones.
 Many of those veins and dykes are associated with pyrite. Pyrite is considered to be a good host
for gold and other base metals. Many paleoproterozoic granitoids have been a renowned site for
such gold deposits. So, there is always a possibility. Hence, further investigation will fully
unravel the potential.
 Now, what’s next after the mining of all the rocks have been done? In many mines around the
world the sub-surface has been converted into a museum that attracts tourists. Maddhapara site
can also be developed in such manner.

9. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
8 | P a g e
Threat:
 Absence of any constructive policy for hardrock by the state.
 Uncertain market.
 Possibility of land subsidence.
 Importing low priced as well as low grade rock from the neighboring countries.
 Insignificant governance by the government.

10. GS-502 Assignment Md. Shahadat Hossain, Roll: 1651
9 | P a g e
References
Ameen S. M. M., Khan M. S. H., Akon E., Kazi A. I., Petrography and major oxide chemistry of some
Precambrian crystalline rocks from Maddhapara, Dinajpur, Bangladesh Geoscience Journal 4 (1998),
p. 1–19.
Ameen S. M. M., Wilde S. A., Kabir M. Z., Akon E., Chowdhury K. R., Khan M. S. H., Paleoproterozoic
granitoids in the basement of Bangladesh: A piece of the Indian shield or an exotic fragment of the
Gondwana jigsaw?, Gondwana Research, 12 (2007), p. 380–387.
Bakhtine M. I., Major tectonic features of Pakistan: Part II, The Eastern Province, Science and Industry, 4
(1966), p. 89–100.
Evans A. M., Ore Geology and Idustrial Minerals-An Introduction, Blackwell Science, 1993, Australia.
Hamrin H., Guide to underground mining methods and applications, Stockholm, Atlas: Copco, 1980.
Kabir M. Z., Chowdhury K. R., Akon E., Kazi A. I., Ameen S. M. M., Petrogenetic study of Precambrian
basement rocks from Maddhapara, Dinajpur, Bangladesh, Bangladesh Geoscience Journal 7 (2001), p.
1–18.
Mines and Minerals Rules, Ministry of Power, Energy and Mineral Resources, 2012, People’s Republic
of Bangladesh.
Reimann K. U., Geology of Bangladesh, Gebrueder Borntraeger, (1993), p. 160.