2. 2
STAG
E
NATURE SCALE OF MAPPING BOREHOLE SPACING
G 4 RECONNAI-
SSANCE
1: 50,000 > 2 km (UPTO 5 TEST BORE
HOLES PER 100 sq km)
G 3 PROSPECTI
NG
1:50,000 TO 1:25,000
(1:10,000 FOR COAL,
LIGNITE ETC.)
1 TO 2 km
G 2 GENERAL
EXPLORATI
ON
1:25,000 TO 1:5,000
(1:10,000 FOR COAL)
400 m TO 1 km
G 1 DETAILED
EXPLORATI
ON
1:1,000 (1:5,000 FOR
COAL)
12 TO 15 BORE HOLES PER
sq km
3. 1. First stage taken up when
investigation activity is initiated
in a virgin area.
2. Identification of specific blocks
for taking up prospecting stage
of exploration.
Activities involved:
1. Study literatures and aerial
photographs and imageries
2. Geological mapping on
1:50,000 scale
3. Ground geophysical surveys(
for broad understanding of coal
seams)
3
Reconnaissance Survey
5. PROSPECTING STAGE
Basic objective:
1. To establish the existence of
coal/lignite horizons
2. Preliminary appraisal of
deposits
3. To demarcate the potential
area for taking up regional
exploration
Activities:
1. Study of old literatures, maps
and aerial photographs
2. Mapping on 1:25,000
3. Geophysical surveys
4. Drilling
GPDW-4 GPDW-1 GPDW-3
50 m
C D
Middle
Kamthi Fm
6. REGIONAL EXPLORATION
STAGE
1. For locating potential coal
bearing areas on a continuous
basis
2. Undertakes only when findings
from the prospecting are
favorable
OBJECTIVES
1. To intersect all regional coal
seams
2. Assessment of resources on
regional basis
3. Delineation of potential areas
for detailed exploration
ACTIVITIES:
1. Mapping on 1:10.000 scale
2. Drilling with borehole spacing
1KM apart( either Grid or Zig-
zag)
3. Studies like CBM
Selection of borehole site
400m
600m
800m
A B
Formational contact
BH
BH BH
200m
C
BH
BH D
Dipping
7. DETAILED EXPLORATION
1. Detailed Exploration is for
actual mine planning
2. Carried out in the potential
blocks identified
3. To intersect the specific group
of seams
4. To ascertain mining feasibility
of one or a group of coal
seams over some particular
area
5. Borehole spacing: 200m to
400m apart
60
80
100m
200m
300m
375m
GEOLOGICAL MAP OF IB BLOCK
BH-1
BH-2
BH-4
BH-6
BH-3
BH-5
BH-12
BH-11
BH-13
BH-14
BH-18
BH-15
BH-10
BH-7
BH-9
BH-8
BH-16
BH-17
Upper kamthi Formation
Barakar Formation
1 CM = 100 M
Scale
100m 200m 300m0
8. GUIDELINES :
1. To intersect max. No. Of seams
2. To intersect seams at shallow depths
3. Sufficiently away from fault planes.
4. Other associated aspects like approachability, water source etc.
5. First borehole usually proposed in the deepest part of the basin
DRILLING AND CORE LOGGING
9. BH-1 BH-2
BH-4
BH-5
GEOLOGICAL MAP OF IB BLOCK B.H. 1
R.L. 355.40
B.H. 2
R.L. 360.60
B.H. 3
R.L. 356.20
B.H. 4
R.L. 365.20
B.H. 5
R.L. 360.20
100m
200m
300m
375m
IV
I
II
IV
IV
IV
IV
III
II
I
III
II
III
II
I
BH-3
A
B
F
A B
B.H. 3
R.L. 356.20
B.H. 4
R.L. 365.20
B.H. 2
R.L. 360.60
IV
III
III
III
F
IV
II
60
70
GEOLOGICAL CROSS SECTION THROUGH A - B
III
IV
II
F
Barren Measures
Barakar
Basement
Coal Seam
Talchir
INDEX
Fault
Strike & Dip
F
10. CATEGORISATION OF RESOURCE
Geological Resources to be classified and codified
as per UNFC
Existing Nomenclature Nomenclature proposed
Term Term Code
Proved Resource MEASURED RESOURCE 331
Indicated Resource INDICATED RESOURCE 332
Inferred Resource INFERRED RESOURCE 333
* Prognosticated
Resource
* RECONNAISSANCE RESOURCE 334
* Not to be included in National Inventory
11. 11
DEVELOPMENT STAGE
Land clearance
Environment clearance
Rehabilitation of population
Transportation through Rail and road
Ground water condition of block
12. THANK YOU
The only way to be sure of catching
a train is to miss the one before it.
