limonitic ore exhibiting folds a mini-ratna company · 2019-02-15 · m/s srinivasalu mine lease...

i

MAY - 2015

TEXT, ANNEXURE AND PLATES

A Mini-Ratna Company

(ML NO. 2631)

MINERAL EXPLORATION CORPORATION LIMITED(A Government of India Enterprise)

Dr. Babasaheb Ambedkar Bhavan,High Land Drive Road, Seminary Hills,

NAGPUR-440 006

Limonitic ore exhibiting folds

MAY - 2015

TEXT, ANNEXURE AND PLATES

A Mini-Ratna Company

(ML NO. 2631)

MINERAL EXPLORATION CORPORATION LIMITED(A Government of India Enterprise)

Dr. Babasaheb Ambedkar Bhavan,High Land Drive Road, Seminary Hills,

NAGPUR-440 006

Limonitic ore exhibiting folds

i

GEOLOGICAL REPORT ON ESTIMATION OF IRON ORE RESERVES/RESOURCES IN RESPECT OF

M/s SRINIVASALU MINE LEASE AREA (ML No.2631) DISTRICT: CHITRADURGA, KARNATAKA

SALIENT FEATURES

1 Name & location of the block

M/s Srinivasalu Mine Lease Area (ML.No.2631) falls in Hiriyur range, Hosadurga Taluk, Dist: Chitradurga, Karnataka, lies between Longitudes E76º26’24.31” and 76º26’27.72” and Latitudes N13º43’08.39” and 13º43’04.00”. The area is covered in Survey of India Toposheet No.57 C/6.

2 Accessibility The mine lease area is 39 km from Hosadurga town, which has railway station also.

3 Objective i) Borehole fixation, determination of coordinates and R.L of boreholes

ii) Detailed geological mapping iii) Estimation of reserves / resources in respect of ‘C’ category mine as per UNFC guidelines

4 Quantum of work a) Geological Mapping b) i) Core drilling ii) RC drilling c) Total Meterage drilled d) Chemical Analysis i) Primary (Fe,SiO2,Al203,) ii) Specific gravity

0.7486 Sq. km (1:1000 RF) 194.50m (4 Bhs) 1027.00m (27 Bhs) 1221.50m (31 Bhs) 1143 Nos and for Mn 31 nos. 11 Nos.

5 Duration of work January 2015 to March-2015 and analysis in the month of May 2015.

6 Geology & structure The Chitradurga basin is elongated narrow belt of 450 kms in length. It narrows southwards and splits up into several linear strips south of Dodguni. The basin is structurally disturbed, followed by later folding and shearing movements and covers an area of about 5550 sq,km. It trends NNW-SSE with an easterly moderate dip. Shelf facies is subordinate confined to a narrow strip along the western margin. In the main, the basin shows characteristics of sedimentation in deep water. The mafic complex to the south of Chitradurga town represents one of the thickest accumulations of pillowed tholeitic basalt associated with pyro clastics. Basement gneiss of smaller dimensions is present. The eastern margin is a thrust contact with mylonite zone. Intrusive granite [2500 Million years] sets the upper limit to the sedimentation.

ii

The change of oxide – carbonate facies with chert and manganese ore [gradually subsiding basin] to sulphide facies with carbonaceous shale, chert layers with dominant pyrite is observed in the deeper parts of the Chitradurga basin. Thus, traced along the strike the iron formation appears differently, having formed under different environments of deposition. Metamorphism of Chitradurga basin is of Green schist facies, at places it graduates into amphibolite facies, though garnets do occur.

7 No. of BHs drilled up to basement

Nil ; Grid pattern : 100 x 100

8 Highest RL in lease area Lowest RL in lease area Deepest BH drilled Intersection-wise

850.861m 720.843m 664.505 mRL (MSVR-5) 737.199 mRL (MSVR-9)

9 Thickness at 45% Fe cut-off

Minimum 0.99m (Bh.No.MSVR8, MSVR- 19) Maximum 43.07m (Bh.No. MSV- 2)

10 Overburden Soil/ Scree, Limonitic clay and BHQ 11 Logging & Sampling 1221.50m and 1143 nos. respectively 12 Samples analysed for 1143 nos. for Fe(%), SiO2 (%), Al2O3 (%) & for

Mn : 31 nos. 13 Average core recovery 85-90% 14 No.of Geological cross-

sections 16 ( S1 – S1’ to S16 – S16’ )

15 Specifications (Based on Fe%)

>45% Threshold value

16 Structure The lease area falls in the Hriyur range trends NW-SE. The bedding trend ranges between N10º-15ºW - S10º-15ºE to N10º-15ºE - S10º-15ºW with steep easterly dip of 75 to 80º.

17 Nature / Type of Ore i) Limonitic ore, Haematitic ore, powdery ore Siliceous ore and clayey iron ore of Vani vilas Formation

ii) Manganese ore has been identified around borehole which also trends as that of Iron ore band. ii) Waste type / OB / IB – Limonitic clay, yellow ochre, limestone, Clay, quartzite and BHQ.

18 Stratigraphy Massive powdery ore, Clayey iron ore, silicious iron ore, Ferruginous Clay, shale/clay and BHQ

19 Ore body dimension Average Strike length :1.8km (eastern, central and western band) Average Wide : 310.00 – 550.00m Average Depth : 26.56m

iii

20 Intercalation Ferruginous clay bands, limonitic clay, clay and Banded haematite quartzite.

21 Ore Reserves (at 45% Fe) 9.880 Million tonnes with 55.08% Fe,6.42 % SiO2 and 7.75 % Al2O3

Fe : SiO2 + Al2O3 ratio is 0.342 Al2O3 : SiO2 ratio is 1.80 Al2O3 : Fe ratio is 8.35

22 Recommendations M/s Srinivasalu mine lease area [ML No.2631] has good potential that would be amenable to systematic scientific mining. It could further yield Manganese, ochre also. However, entire area has good limestone potential for cement manufacture. In addition, ochre could also been exploited for the usage in pigment industry.

iv

GEOLOGICAL REPORT ON

ESTIMATION OF IRON ORE RESERVES/RESOURCES IN RESPECT OF M/s SRINIVASALU MINE LEASE AREA (ML No.2631)

DISTRICT: CHITRADURGA, KARNATAKA

LIST OF CONTENTS

CHAPTER NO.

CONTENTS PAGE NO.

SALIENT FEATURES i-iii

CHAPTER-1 1-3

1.0.0 INTRODUCTION 1

1.1.0 General 2

1.2.0 Location and Accessibility 2

1.3.0 Physiography 2

1.4.0 Climate 2

1.5.0 Scope of Work 2

1.6.0 Acknowledgements 3

CHAPTER-2 4-8

2.0.0 REGIONAL GEOLOGY & STRUCTURE 4

2.1.0 Background Information 4

2.2.0 Classification of Iron Ore Deposits 5

2.3.0 Regional Geology and Structure 7

2.4.0 Structural Control 8

2.5.0 Metamorphism 8

CHAPTER-3 9-15

3.0.0 EXPLORATION BY MECL 9

3.1.0 Objective 9

3.2.0 Summary of Exploration work done 9

3.3.0 Surface Survey 9

3.4.0 Geological Mapping 10

3.5.0 Exploratory Drilling 13

3.6.0 Core Logging 13

3.7.0 Primary Sampling 13

3.8.0 Specific Gravity Determination 14

v

CHAPTER NO.

CONTENTS PAGE NO.

CHAPTER-4 16-19

4.0.0 MINERALISATION AND CHARACTERISTICS OF IRON ORE

16

4.1.0 Mineralisation 16

4.2.0 Types of Ore 16

4.3.0 Grade Classification 17

4.4.0 Depth Persistence 18

4.5.0 Mineralisation Factor 18

4.6.0 Physical Characteristics of Ore 19

4.7.0 Chemical Characteristics of the Iron Ore 19

4.8.0 Orebody dimension 19

CHAPTER-5 20-23

5.0.0 METHOD OF RESOURCE ESTIMATION 20

5.1.0 Resource estimation by geological cross-section 20

5.2.0 Shape of Ore body 20

5.3.0 Estimation of Reserves / Resources and Grade 21

CHAPTER-6 24-33

6.0.0 RELIABILITY OF ESTIMATION 24

6.1.0 Frequency Distribution 24

6.2.0 Accuracy of Analytical Procedure 24

CHAPTER-7 34

7.0.0 CONCLUSIONS AND RECOMMENDATIONS 34

7.1.0 CONCLUSIONS 34

7.2.0 RECOMMENDATIONS 34

f


ESTIMATION OF IRON ORE RESERVES IN RESPECT OF M/s SRINIVASALU MINE LEASE AREA (ML No.2631)


LIST OF ANNEXURES

ANNEXURE No.

TITLE PAGE

No.

I Details of Triangulation Stations 1-2

II Details of Survey particulars of boreholes drilled by MECL

1-2

IIIA Detailed Litholog of boreholes drilled (core drilling) by MECL

1-10

IIIB Detailed Litholog and analytical details of boreholes (Reverse Circulation drilling) drilled by MECL.

1-41

IV Analytical Results of Primary Samples (Core Drilling] 1-6

V Details of Concise litholog of boreholes 1-31

VI Contract Agreement 1-9

LIST OF TABLES

TABLE NO.

TITLE PAGE

No.

1 Quantum of work executed in M/s Srinivasalu Mine Lease Area

2

2 Details of Iron Ore zone Intersected in the Boreholes (at 45% Fe cut-off)

17

3 Details of Iron Ore zone Intersected in the Boreholes (at 50%Fe)

18

4 Estimation of reserves (at 45 % Fe cut-off) by cross section method

23

g


ESTIMATION OF IRON ORE RESERVES IN RESPECT OF M/s SRINIVASALU MINE LEASE AREA (ML No.2631)


LIST OF PLATES

No. TITLE R.F.

I Location Map 1 : 200000

II Regional Geological Map 1 : 2000

III Topographic and Geological Map M/s Srinivasalu Mine Lease Area

1 : 1000

IV Graphic Llithologs with Histograms 1 : 500

V Geological Cross Sections (S-1 - S-1’ to S-4-S-4’) 1 : 1000

LIST OF TEXT PLATES

TEXT PLATE

NO. TITLE

PAGE NO.

1 Iron Ore Deposits of India 6 2 Typical geological cross section 22 3 Histogram of Primary Sample Assay (Entire data)-Fe2O3 25 4 Histogram of Primary Sample Assay (Entire data)-Sio2 25 5 Histogram of Primary Sample Assay (Entire data)-Al2O3 26 6 Distribution of Primary samples grade (entire data) Fe2O3 (Log plot) 27 7 Distribution of Primary samples grade (entire data) Sio2 (Log plot) 28 8 Distribution of Primary samples grade (entire data) Al2O3 (Log plot) 29

9 Distribution of Primary samples grade (Zone data) Fe2O3 (Log plot) 30 10 Distribution of Primary samples grade (Zone data) Sio2 (Log plot) 31 11 Distribution of Primary samples grade (Zone data) Al2O3 (Log plot) 32

1

GEOLOGICAL REPORT ON ESTIMATION OF IRON ORE RESERVES / RESOURCES IN RESPECT OF

M/s SRINIVASALU MINE LEASE AREA (ML No.2631) DISTRICT: CHITRADURGA, KARNATAKA

CHAPTER - 1 1.0.0 INTRODUCTION 1.1.0 GENERAL 1.1.1 The extensive exploitation of Iron ore by small and large lease area holders by

violating all norms fixed by the government, besides the illegal mining beyond their lease boundary by few mine owners forced the government to stop mining activity and cancel the mining leases since September 2011 by the verdict of Hon’ble Supreme Court of India in its Order dated: 24.02.2014. Accordingly a committee was formed to assess the extent of encroachment / violation based on the joint survey conducted by authorities under the Chairmanship of the Chief Secretary to Government of Karnataka. Considering the extent of encroachment, 51 mines have been grouped under C-category mines and the mining licenses of these mines were cancelled. As per the guidelines Director, Department of Mines and Geology vide letter no. GO No.CI79MMM 2013 [Vol-III] Bengaluru dated 14-11-2014 for carrying out exploration on estimation of iron ore reserves / resources for 9 C category mines in Sandur of Ballari and 2 mines in Chitradurga district. The subsequent detailed discussions with official of IBM, DMG and MECL, it was decided to restrict core drilling method to less than 20% and enhance the RC drilling to more than 80%.

1.1.2 MECL officials visited 15 abandoned C-Category iron ore mines in Sandur area

of Ballari district and Hiriyur area of Chitradurga district along with DMG officials between 19-3-2014 to 23-3-2014 in prelude to the exploration in the C-Category mines. It is observed that, no systematic mining being done, no old exploration / Borehole data or chemical data and no updated Surface Plan is available for planning further exploration.

1.1.3 Based on the available Surface Plan and GPS Survey data provided by DMG

Karnataka, the proposal for detailed exploration for iron ore in 9 abandoned C category mines located in Ramgad Range, NEB Range in Ballari district and 2 mines in Chitradurga district, Karnataka were prepared.

1.1.4 Chitradurga Schist Belt is one of the schist belts of Dharwar Super Group

occupied in about 5550 Sq.km area between Chikkanayakanahalli in the north to Yarahalli in the south. The belt is known for copper, gold which has been mined around Chitradurga town at Ingaldal upto a vertical depth of 300m by Hutti gold mines. Iron and Manganese ores also have been mined by ancient people.

1.1.5 In future, almost entire Europe (excluding former USSR), Japan, Korea, China

and other Asian Countries will nearly depend upon import of iron ore. The main exporters will be Brazil, Oceania [Australia, New Zealand etc.) and former USSR. India has a good export market in the eastern sector as Australia seems to be the sole major competitor; besides, India has a good market even

2

in Europe and Africa. Therefore, it is pertinent to explore large areas to cater to heavy export of iron ore.

1.2.0 LOCATION AND ACCESSIBILITY 1.2.1 M/s Srinivasalu Mine Lease area (ML No.2631) falls The lease area falls in the

Hriyur range and approachable by road from Hosadurga at a distance of 39km. The area is bounded by Longitudes E76º26’24.31” and 76º26’27.72” and Latitudes N13º43’08.39” and 13º43’04.00”. The railway station is in Hosadurga on Bengaluru-Harihar broad-gauge line of SWR.

1.2.2 The Chitradurga Schist Belt extends over a strike length about 450 km

Chikkanayakanahalli in the north and Yerrahalli in the south. The area is covered in Survey of India Toposheet Nos.57 C/6.

1.3.0 PHYSIOGRAPHY 1.3.1 Physiography of the area is characterized by two elongated ridges trending

NW-SE. No nalla runs thorough the area. The surface area is covered by float iron and iron ore bands.

1.4.0 CLIMATE 1.4.1 The area of Chitradurga district experience dry semi arid climate with annual

rainfall varying from 40cm to 80cm. The monsoon begins in June first week and continues up to September and winter from the month of October to January is some what pleasant However, hot to very hot summer is from the month of February to May.

1.5.0 SCOPE OF WORK

TABLE-1:

QUANTUM OF WORK EXECUTED IN M/s SRINIVASALU MINE LEASE AREA (MLNo.2631)

Sl. No Activity Quantity

1 Topographical Survey - on 1:1000 scale ( Dove tailing of data provided by DMG,Karnataka)

74.86 Ha

2 Geological Mapping 0.7486 sq. km.

3 Survey

i) Triangulation/Traversing 74.86 Ha

ii) BH Fixation 31 Nos.

iii) Determination of RL & Co-ordinates 31 Nos.

3

Sl. No Activity Quantity

4 Exploratory Drilling

i) Core Drilling 194.50 m ( 4 Bhs)

ii) RC Drilling 1027.00m. ( 27 Bhs)

5 Geological Activities

i) Core Logging 1221.50 m

ii) Sampling 1143 Nos.

6 Chemical Analysis :

i) Primary (Fe,Sio2 &Al2O3)

ii Primary - Manganese

1143 Nos.

31 Nos.

ii) Specific Gravity determination 11 Nos.

1.6.0 ACKNOWLEDGEMENTS 1.6.1 MECL is highly thankful to Ore resource estimation committee for its

suggestions and valuable guidance in planning and execution of the proposed exploration in ‘C’ - Category iron ore mines of Ballari – Hospet and Chitradurga area, Karnataka.

1.6.2 MECL places on record its profuse thanks to Director, Directorate of Mines and

Geology, Karnataka for assigning the responsibility of exploration in M/s Srinivasalu Mine Lease Area (MLNo.2631), Chitradurga district, Karnataka.

1.6.3 MECL also gratefully acknowledges the co-operation in execution of exploration

activity at M/s Srinivasalu Mine Lease Area (MLNo.2631) by the officials of Directorate of Mines & Geology, Chitradurga.

4

CHAPTER-2

2.0.0 REGIONAL GEOLOGY AND STRUCTURE 2.1.0 BACKGROUND INFORMATION 2.1.1 H. James defined iron formation as a “Chemical sediment, typically thin bedded

or laminated, containing 15% or more iron of sedimentary origin and commonly but not necessarily containing layers of Chert”. Banded Iron Formation (BIF) has been formed within a single epoch of earth between 1900 and 2500 million years ago. The amount of iron deposited in this epoch of sedimentation is quite enormous.

2.1.2 The pre-Cambrian banded iron formations which are known as IRON

FORMATIONS or IRON ORE SERIES consists of banded haematite quartzite, banded haematite jasper, banded chert, etc. in the un-metamorphosed state; whereas on metamorphism, the bounded ferruginous rocks have given rise to banded magnetite quartzite in which, the magnetite has been derived from the original haematite and in places from grunerite - cummingtonite bearing rocks. The basic eruptive rocks of the Precambrian time are the major source of iron ores. The iron ores have been deposited through sedimentary resources followed by leaching, oxidation by surface water percolation over a long period and re-cementation with some replacement have also played a part at places. The haematite generally occupies the top of the ridges and hillocks, which are of great magnitude. Most of the ores have grade of > 60% and are in association with ores of medium and lower grade in larger quantities. The grain size varies from fine to coarse. Few grains of martite and magnetite are present, which are of not much significance. Due to weathering haematite have altered to limonite & goethite and finally to laterite at places.

GEOLOGICAL DISTRIBUTION OF INDIAN IRON ORE DEPOSITS

Formation Type of Deposits Areas of occurrence

Quarternary Laterite Small occurrences widely scattered as derived from many formations including Deccan Traps.

Tertiary Eocene and Miocene

Ironstones

NE Regions [Assam] Kumaon Hills, Travancore, Malabar coast.

Jurassic Rajmahal Trap (inter trappean beds)

Ironstones

Birbhum, West Bengal. Rajmahal Hills, Bihar

Formation Type of Deposits Areas of occurrence Triassic Sirban limestone

Haematite and limonite

Udhampur, Kashmir

5

Gondwana Ironstone

Ironstone and Siderite

Raniganj Coalfield

Barakar Mahadeva Ironstone and Siderite Birbhum, Auranga Coalfield Cuddapah Bijawar, Gwalior, Cuddapah

Haematite and Ferruginous, Quartzite

Bijawar, Gwalior, Indore, Rewa, Mahendragarh, Jaipur, Jhunjhunu, Sikar, Cuddapah

Banded Iron Formation (Metamophosed)

Magnetite-Quartzite Guntur, Salem, Tiruchira- palle, Shimoga, Chikmaglur Mandi (Himachal)

Banded Iron Formation

Haematite (massive, shaly, powdery etc).

Singhbhum, Bonai, Keonjhar, Mayurbhanj, Poonch (Kashmir), Bastar, Durg, Jabalpur, Chandrapur, Gadchroli, Ratnagiri, Dharwar, Ballari, Shimoga, Chikmaghur, Goa.

Granites Magnetites (Residual) Jaintia Hills (Assam) Granodiorites (Rampahari Granite)

Apatite-Magnetite rock Singhbhum, Mayurbhanj

Basic Ultra basic rocks

Titaniferous-vanadiferous magnetites

Singhbhum, Mayurbhanj

Pre-Cambrians Magnetite SE Karnataka, Mysore 2.1.3 The BIF has great economic potential, as it hosts many useful metalliferrous

ores such as iron, aluminum, copper, chromium, gold, uranium, etc. 2.2.0 CLASSIFICATION OF IRON ORE DEPOSITS: 2.2.1 The iron ore resources of India are mainly distributed within the five major

zones as detailed below:

6

GEOGRAPHICAL DISTRIBUTION [GSI’s Bulletin series A, No.51 (1988)]

(Text Plate-1)

ZONE

A Chiria, Noamundi, Kiriburu, Meghahatuburu, Thakurani, Bolani, Gua, Malong toil, Gandhamardan, Daitari.

B Bailadila, Dalli, Rajhara, Rowghat, Mahamaya, Aridongri, Surajgarh.

C Donimalai, Ramgad, Kumaraswamy, NEB Range, Ettinahatti, Tumti, Belagal.

D N.Goa, S.Goa, Redi.

E Kudremukh, Bababudan, Kudachadri.

2.2.2 Also less important (deposits) belts are around central Madhya Pradesh,

Rajasthan, Haryana, Tamilnadu, Andhra Pradesh etc.

TEXT PLATE-1

IRON ORE DEPOSITS OF INDIA

7

2.3.0 REGIONAL GEOLOGY AND STRUCTURE 2.31 The Chitradurga basin is an elongated narrow belt of 450 kms in length. It

narrows southwards and splits up into several linear strips south of Dodguni. The basin is structurally disturbed, followed by later folding and shearing movements and covers an area of about 5550 sq.km. It trends NNW-SSE with an easterly moderate dip.

2.3.2 Shelf facies is subordinate confined to a narrow strip along the western margin.

In the main, the basin shows characteristics of sedimentation in deep water. The mafic complex to the south of Chitradurga town represents one of the thickest accumulations of pillowed tholeiitic basalt associated with pyro clastics. Basement gneiss of smaller dimensions are present. The eastern margin is a thrust contact with mylonite zone. Intrusive granite [2500 Million years] sets the upper limit to the sedimentation.

2.3.3 The meta basalts are found in totally different environment and show well

preserved pillow and variolitic structures. They are least deformed agglomerates, tuffs and cherts are very common. The associated iron formation is of the sulphide facies. Basalts show excellent quench textures. Metabasalts constitute nearly 60% of the volcanic pile in the lower sections and andesites, rhyolities and pyroclastics in the upper sections.

2.3.4 The change of oxide – carbonate facies with chert and manganese ore

[gradually subsiding basin] to sulphide facies with carbonaceous shale, chertlayers with dominant pyrite is observed in the deeper parts of the Chitradurga basin. Thus, the iron formation appears differently and traced along the strike, having formed under different environments of deposition.

2.3.5 It seems shore to depth arrangements of oxide, carbonate and sulphide facies

in a sinking volcanic sedimentary basin [Goodwin 1973]. 2.3.6 Metamorphism of Chitradurga basin is of Green schist facies, at places it

graduates into amphibolite facies though garnet do occur. 2.3.7 Mineralisation: The low grade granite – greenstone terrain [3500-2500m.y] is

the repository of a number of economically important mineral deposits of iron, manganese, gold, copper, chromium and nickel. Most of the deposits are associated with greenstone belts. Crustal development is marked by specific mineral deposits characteristic of particular stage in its evolution. Structure has played an important role by providing suitable dilatant zones of low pressure in which mineralization solutions could migrate. Stratigraphy too has exercised control especially in the localisation of deposits of iron and manganese ores. The generalized stratigraphic sequence of Chitradurga belt is as follows:

8

Hiriyur Formation Greywacke – argillite suite with volcanics, pyroclastics,

cherts and polymict conglomerates. Ingaldhal Volcanics

Basic volcanics and Pyroclastics, acid volcanics, cherts and phyllites.

Vanivilas Formation

Iron and manganese formations, limestones, dolomites, phyllites and quartzities. Talya and Dodguni conglomerates.

Javanahalli Formations

Amygdular basalt and clastics and associated para gneisses. Neralkattee quartz pebble conglomerate, quartzities

----------------------------Unconformity--------------------------- Basement gneisses

2.3.8 The hill ranges of Sandur Schist Belt appear to be isoclinal synclines trending

NNW – SSE with general northeasterly dip. The major valleys are in the anticlinal regions. The Copper Mountain (Belagal), Thimmappanagudi, Ramgad, Kumaraswamy and Donimalai ranges are located in the synclinal regions. The overall structure of the schist belt is synclinal and it is often called “Sandur Synclinorium”

2.3.9 The eastern and western limbs of Sandur Syncline and Copper Mountain cross

folded syncline show only iron ore enrichment. The en-echelon drag fold shows concentration of manganese ore along the troughs and the saddles.

2.4.0 STRUCTURAL CONTROL 2.4.1 Iron ore, banded ferruginous cherty quartzite, are intimately associated with

gabbro of pre-tectonic and post tectonic origin. 2.4.2 The hill ranges trend in NW-SE direction, which are similar to the regional

tectonic trend of the Sandur Schist Belt. The area has under gone two phases of deformation [F1 and F2] and metamorphism. The axial trace of F1 have NNW-SSE trend which is refolded by open F2 folds trending ENW-WSE. The primary structure of banded iron ore formation is bedding and pene-contemporaneous faults. Schistosity and fracture cleavage are common. The repetitions of iron ore bands, which cause the thickening of ore at places, are due to diastrophic folds.

2.5.0 METAMORPHISM 2.5.1 Metamorphism of Chitradurga basin is of Green schist facies, at places, it

graduates into amphibolite facies though garnet do occur.

9

CHAPTER-3

3.0.0 EXPLORATION BY MECL 3.1.0 OBJECTIVE 3.1.1 The main objective of exploration by MECL is to estimate the iron ore resources

in M/s Srinivasalu Mine Lease Area (M.L. No.2631). The following objectives were set for this purpose:

i Borehole fixation, determination of boreholes co-ordinates and RL

ii To prepare geological map of the mine lease area besides planning and fixation of exploratory boreholes

iii) To assess the strike and depth continuity of iron ore in the mining lease

area iv) Estimation of iron ore reserves / resources as per UNFC classification

3.1.2 Based on the work order of DMG, Karnataka, the exploration was commenced

on 18.01.2015 and completed on 04.03.2015 involving 194.50m core drilling in 4 boreholes and 1027.00m in 27 boreholes by RC drilling thus amounts to a total of 1221.50m in 31 boreholes. 1143 nos. primary samples have been analysed for Fe, SiO2 and Al2O3 besides 31 nos. for Mn. 11 nos. samples have also been studied for specific gravity determinations. The chemical analysis was completed on 02.05.2015.

3.2.0 SUMMARY OF EXPLORATION WORK DONE 3.2.1 The summary of physical work done by MECL is given in Table 1.1. The

detailed account of each activity is presented in the following paras. 3.3.0 SURFACE SURVEY 3.3.1 The survey work has been carried by using Differential Global Positioning

System (DGPS) of Tremble make having an accuracy of 0.10 m with WGS 1984 datum. The surveyed map of the mining lease area has been provided by DGM, Karnataka. The boreholes have been fixed and RL determined by triangulation method. The triangulation stations details and co-ordinates and borehole header details have been provided as Annexure-I and II.

3.3.2 The base map has been provided by DMG, Karnataka as surveyed by NIT,

Suratkal, Karnataka. The co-ordinates, both National and UTM, of triangulation stations and boundary pillars of the base map were also provided by DMG, Karnataka. The survey work by MECL has been continued to prepare the geological map on 1:1000 (Plate-III) and fixation of boreholes by using the Electronic Total station (Sokkia make).

10

3.4.0 GEOLOGICAL MAPPING 3.4.1 The geological mapping was carried out with the help of tape and compass

over an area of 0.7486 sq.km on 1:1000 scale. The survey stations fixed on the cross sections line were used as reference points.

3.4.2 During the exploration, the benches dug were also studied carefully to decipher

and delineate the nature and behavior of iron ore bands. Other formations as well as surface geological features were also incorporated in the topographical and geological map. Structural features viz. attitude, different formations, joints, foliation etc. were also recorded and provided in Plate-III. A few field photographs have been appended [Field Photo-1 to 4].

11

Field Photo-1 : Mining pit western side of Cross section S11-I

Field Photo-2 : SE corner of the mine between Cross section S18-S19-I

12

Field Photo-3: SE corner of the mine between Cross section S18-S19-II

Field Photo-4:SE corner of the mine between Cross section S18-S19-II

13

3.5.0 EXPLORATORY DRILLING 3.5.1 The boreholes have been released as per the proposal approved by DMG,

Karnataka. The boreholes have been drilled by MECL and closed in consultation with DGM officials at Ballari. In order to assess total potential of iron ore in the mine area, a total of 4 no. of boreholes for core drilling and 27 no. of boreholes for RC drilling have been planned involving of 194.50m and 1027.00m respectively. Thus, a total of 1221.50 m (31 BHs) exploratory drilling has been completed in M/s Srinivasalu Mine lease area (ML No.2631). During the period of execution, due to the finer nature of ore, utmost care has been taken while drilling, so as to achieve maximum core recovery. In the mineralized zone, the overall recovery has been 85-90% and above.

3.6.0 CORE LOGGING 3.6.1 The core and powdery materials recovered from drilling were logged

systematically to demarcate various litho-units. The logging of run wise cores and the powdery materials as well as the cuttings from boreholes have helped in discerning physical characters like colour, shape, size and nature of pieces [laminated, goethite, clayey, and siliceous etc. Besides these, the qualitative analytical data were helped in delineating the ore types and non ore. Among the non ore, ferruginous shale, shale banded hematite quartzite has also been demarcated. The upper portion of ore body has been covered invariably by laterite / lateritic ore. However, impersistent remnant banded hematite quartzite have been observed at few places. Based on these observations, ore zones and non-ore horizon were distinguished and delineated after chemical analysis and lithological details were given in Annexure IIIA, IIIB and IV. In order to generate graphic lithologs, concise lithologs were prepared (Annexure-V) and presented in Plate-IV.

3.7.0 PRIMARY SAMPLING 3.7.1 The core recovered by drilling was divided into two longitudinal halves. One

half was taken for sampling, whereas the second half was kept for future reference [with DGM, Karnataka]. The first half was subjected to uniform size reduction of 1mm size. It is thoroughly mixed pounded and powdered to (-) 100 mesh size by pestle and mortar and then coned and quartered. 3 sample packets of 100 gram each have been prepared; out of the three, one packet was handed over to DGM, Karnataka and the other one has been labeled and sent to MECL laboratory for Fe, SiO2 and Al2O3 analyses, whereas the third packet has preserved for future reference. However, wherever required some of the samples amounting to 31 nos. were also analysed for Mn determinations by classical methods. Generally, one meter length of the core has been considered as a sampling unit, provided no change in lithology or else, the length corresponds to particular lithology has been taken into consideration for sampling purposes. The analytical details of the samples have been given in annexure IIIB and IV.

14

3.7.2 The entire lot of chips and powder material were collected from boreholes drilled by Reverse Circulation drill. 50% mostly of chip samples have been thoroughly mixed to have the desired quantity of 500-600 gms. and pounded to (-)100 mesh size by progressive reduction, 3 sample packets of 200 gram each has been prepared; out of the three, one has been labeled and sent to MECL laboratory mostly for Fe, SiO2 and Al2O3 analyses, at places where wherever required for determination of Mn. The other packet was handed over to DMG, Karnataka, and the 3rd packet of the sample has been preserved for further studies at camp.

3.7.3 Chemical Analysis: All the primary samples were analysed for Fe, SiO2, and

Al2O3 at MECL laboratory by classical method and at JNRDC laboratory by XRF method. The details of analysis are provided in Annexure-IIIB.

3.7.0 SPECIFIC GRAVITY DETERMINATION 3.7.1 The specific gravity of different types of ores has been determined on samples

by Walker’s Steelyard Balance method in the MECL laboratory. The results are given below:

Sl.No. Sample No. Lithology Specific Gravity

1 SV-1 Ochre 1.95 2 SV-2 Massive Ore 3.67 3 SV-3 BHQ 3.58 4 SV-4 Limonitic Ore (Powdery) 2.92 5 SV-5 Yellow Ochre 1.93 6 SV-6 Flaky Ore 2.74 7 SV-7 Flaky Laminated Ore 2.95 8 SV-8 Clay + Manganese Ore 1.97 9 SV-9 Quartzite 2.60

10 SV-10 Float Ore 3.35 11 SV-11 Brown Ochre 1.97

3.7.2 However, bulk densities determined by different deposits by various agencies

are also given below:

Determination of Bulk density by GSI in NEB Range

Ore Zone Hard Ore Soft Ore Powder Ore I 3.4 3.0 II - - 3.0

III - - 3.0 IV 4.9 3.0 3.0

V 4.7 3.3 3.0 V-A 4.4 3.0 3.0 X 4.35 3.07 3.0

Mean 4.35 3.07 3.0

15

Determination of Specific Gravity by IBM in Chitradurga – Hospet deposit

Lumpy ore 3.5

Blue Dust 3.8 Mean 3.65

Determination of Specific Gravity by NMDC in Bailadila deposit no.4

Steel grey hematite 4.2 Blue grey hematite 4.0 Laminated hematite 3.5

Lateritic & Limonitic ore 3.5 Flaky ore & Blue dust 3.4

Mean 3.72

Overall Specific Gravity after consideration of all the deposits is 3.50

16

CHAPER-4

4.0.0 MINERALISATION AND CHARACTERISTICS OF IRON ORE 4.1.0 MINERALISATION 4.1.1 The core samples with more than 45% Fe and above have been considered as

the iron ore. The ore exhibits wide variations of physical properties ranging from compact, hard and massive ore to soft, granular, laminated and reddish brown powdery ore.

4.1.2 However, categorization/classification of the ore based on quantitative data

such as hard, soft, laminated, powdery etc., have been possible based on mine data (size range or granulometry). It is also based on physical properties like colour, presence or absence of weakness, cohesiveness of the grains etc. This lithological classification helped in revealing a stratigraphical picture of the relative preponderance of different ore types.

4.1.3 The iron ore in nature is not homogeneous, but consists of a mixture of many

ore types. Hence, practical approach of demarcating the ore zones based on predominant nature of the lithology/ore substantiated with analytical data have been applied.

4.2.0 TYPES OF ORE 4.2.1 Various types of iron ores are derived from haematite viz. massive ore,

laminated ore, low grade iron ore, Manganese and powdery ore.

Type of Ore Characteristic Features

Lateritic Porous and cavernous in nature Laminated Closely spaced laminae, which give rise to biscuity

ores. Blue dust (-)10 mesh Ore constituting of haematite and martite Massive (Haematitic) No planar structure

4.2.2 Ferruginous clay has been intruded over the strike length of 668.0m between

S1 to S6. In the north western corner of the lease area over 200.0 m strike line low grade iron ore occur with predominant float ore and trends in the NW-SE direction.

4.2.3 The Manganese ore occur mostly as wad and pockets in the form of powdery and black in colour. Rich manganese ore has been found in the north and northwestern side of the lease area. Primary samples of 31 nos. have been analysed for manganese determinations. The results are provided in the Annexure-IIIB and IV.

4.2.4 Limestone has been mapped in the central part of the area between S-7 and

beyond S-8, north western side of S-9 and eastern side mine lease area. The limestone has been encountered in the boreholes MSVR-10and MSVR-11 is of moderately good quality, which could be used for manufacture of cement. Float ore has been encountered in the north western periphery, middle of S-11 and S-12, S-14 and southwestern side of S-13.

17

4.2.5 The ochre which has been traced in the southeastern and southwestern part of the lease area between S-14 and S-16. It is of good quality which could be used in the pigment industry.

4.2.6 The area between section S8 and S9 over 500 m strike length has limestone exposures; due to non-approachability, the same has not been explored.

4.2.7 Low grade iron ore has been further exposed over the wide area of 190 to 445 m along the strike length of 645 m between S9 and S15 section in NW-SE direction. However limonitic clay/ore has been intruded.

4.3.0 GRADE CLASSIFICATION 4.3.1 The exploration efforts in 70’s were mainly for lumpy ores. Fines were not

given economic importance. Similarly, exploration will also be required to categorize the ore reserves / resources based on end user’s grade classifications. At threshold cutoff of 45% Fe as stipulated by IBM Fe cutoff, the mineralized zones within the lease hold area have been delineated and presented in the Table-2 and Table-3 respectively.

Table-2: DETAILS OF IRON ORE ZONE INTERSECTED IN THE BOREHOLES (AT 45% Fe CUT-OFF)

BH.No. From (m)

To (m)

Thick. (m)

True Thick.(m)

Grade %

Fe SiO2 Al2O3

MSV-1 0.00 6.50 6.50 6.45 42.81 7.39 20.09

10.00 50.50 40.50 40.16 61.16 2.67 3.13

MSV-2 1.50 45.00 43.50 43.14 55.64 5.38 7.80

MSVR-9 2.00 5.00 3.00 2.97 50.16 4.17 14.96

MSVR-13 2.00 17.00 15.00 14.85 48.51 1.98 20.78

MSVR-14 0.00 11.00 11.00 10.89 49.67 1.30 19.44

23.00 31.00 8.00 7.92 49.38 0.77 22.52

MSVR-15 0.00 26.00 26.00 25.74 57.99 2.80 6.96

MSVR-16 33.00 39.00 6.00 5.94 45.35 29.41 1.78

48.00 49.00 1.00 0.99 48.74 1.02 28.76

MSV-18 0.00 8.00 8.00 7.94 55.12 4.62 6.20

MSVR-20

0.00 11.00 11.00 10.89 52.91 8.61 9.98

29.00 59.00 30.00 29.70 55.27 7.71 5.70

63.00 67.00 4.00 3.96 45.59 13.73 12.72

MSVR-22 12.00 39.00 27.00 26.73 57.60 7.06 4.61

42.00 47.00 5.00 4.95 53.19 6.86 8.77

18

Table-3:

DETAILS OF IRON ORE ZONE INTERSECTED IN THE BOREHOLES

(AT >35% and < 45 Fe% CUT-OFF)

BH NO FROM (m) TO (m) Thick. (m) Fe

%

MSVR-11

0.00 2.00 1.98 33.36

6.00 8.00 1.98 30.94

MSVR-14 11.00 23.00 11.88 43.28

31.00 35.00 3.96 43.28

MSVR-15 26.00 46.00 19.80 36.73

MSVR-16 0.00 36.00 35.64 37.27

39.00 49.00 9.90 37.90

MSVR-17 0.00 33.00 32.67 29.23

MSVR-19 0.00 10.00 9.90 35.68

MSVR-20 11.00 28.00 16.83 36.54

MSVR-21 0.00 4.00 3.96 31.43

MSVR-22 47.00 52.00 4.95 38.78

MSVR-23 0.00 12.00 11.88 30.51

MSVR-24 0.00 16.00 15.84 28.40

MSVR-25 0.00 25.00 24.75 30.24

MSVR-26 18.00 25.00 6.93 40.73

MSVR-30 0.00 4.00 3.96 33.63

4.4.0 DEPTH PERSISTANCE 4.4.1 The general mode of occurrence of hematite deposits which, form bulk of the

ore resources in the country, is in the form of surface enrichment. The ore band occurs as reef is in the form of pure sedimentary beds with steep dip of 75º -85º easterly dip. The average depth of the mineralised zone proved by the present exploration in the present mine lease area is 26.56m over 1.8 km strike length. However, over an area of 500m has not been covered by exploration due to non approachability between S8 and S9 sections.

4.5.0 MINERALISATION FACTOR 4.5.1 Mineralogy of an iron deposit has a great influence in the ore treatment

characteristics and economics. Magnetite is recoverable by relatively simple, economical magnetic separation while, haematite, goethite, siderite require expensive roasting or flotation processes. Although when the grains are coarse, haematite ore may get treated with low cost. Mineralisation factor is the ratio of net ore bearing area to gross area. It is referred as the co-efficient of impurities. Out of the mining lease area of 0.7486 sq.km, the mineralized area is 30490.01 sq. m. The mineralization factor for M/s Srinivasalu Mine Lease Area is 4.07.

19

4.6.0 PHYSICAL CHARACTERISTICS OF ORE 4.6.1 The types of ore present in this block are massive + laminated, soft laminated,

Limonitic ore, powdery and siliceous ore. 4.6.2 Principal ore minerals are haematite + magnetite, goethite and limonite. 4.7.0 CHEMICAL CHARACTERISTICS OF THE IRON ORE 4.7.1 In the entire deposit, the high grade ore is almost free from lateritisation and the

laterite area is very less (2-3%). The haematitic ore persists even beyond the level of exploration as could be visualize from the geological cross sections (S-1 & S-3).

4.7.2 Silica to Alumina ratio ranges between 0.0341 and 16.522 with the average of

1.806 indicating low level of lateritisation. The ore are in general, moderately rich in iron [>50%Fe], but they also contain 1.78 to 22.52% Al2O3 and the ore deposits normally have Al2O3: Fe ratio around 8.353.

4.8.0 ORE BODY DIMENSION 4.8.1 At 45% Fe cut-off, over the strike length of 1800 m, the geometry of the iron ore

bands is given below.

Overall Low grade iron ore

Strike length (m) 1800m(S1-S16) 644.50m (S9-S15) Av. Wide area (m) 310 - 570.00 190 – 445.00 Av. True thick (m) 26.56m Trend NW-SE Grade % Fe 55.08

SiO2 6.42 Al2O3 7.75

With predominant float ore

The float ore patch has been traced between cross section S-13 to S-15 and

beyond, S-5 to S-8 and a small patch mid of cross section S-9 (north). However, iron ore still persists beyond the explored depth as could be visualized from the cross section S-9, S-10, S-11, S-12 and S-14.

20

CHAPTER-5

5.0.0 METHOD OF RESERVES ESTIMATION 5.1.0 RESERVES ESTIMATION BY GEOLOGICAL CROSS-SECTION 5.1.1 Resources have been estimated by geological cross section method. In order

to delineate the ore and non-ore, the grade or threshold value of 45% Fe has been adopted, thus non ore above and below ore zones has been demarcated. The rule of gradual change or law of linear function has been applied [Constantine C. Popoff, 1965] along with the rule of nearest points for application of influence of half way between successive boreholes.

5.1.2 At threshold cutoff of 45% Fe as stipulated by IBM, the mineralized zone within

the lease hold area and the ore reserves are estimated. 5.1.3 A total of 16 cross sections serially numbered S1-S1’ to S16-S16’ from west to

east along N58°E-S58°W have been prepared (Plate-V) based on the interpretation of sub surface borehole qualitative data along with surface geological data which is perpendicular to general strike of the ore body. A typical cross section along section line S9 is given as Text Plate-2.

5.1.4 50.0 m on either side of the iron ore intersection of the borehole has been

placed under (G1) and the rest under (G2) category of UNFC. 5.1.5 Correction factor of 1.003 for Thickness of Iron ore in strike direction has been

applied. Similarly a correction factor of 0.99 has been applied to get true thickness.

5.1.6 A call factor of 10% reduction has been applied to arrive at net geological

reserves. 5.2.0 SHAPE OF THE ORE BODY 5.2.1 The shape of the ore body has been obtained by interpretation and correlation

of the borehole data. Each borehole gives a point for the location in space of the ore bottom which, in general is either limonitic iron ore or clayey iron ore. Hence, iron ore persists even beyond the explored depth.

5.2.2 The possibility of the ore body being in the nature of sedimentary bed,

behaving as a stratigraphic unit was considered. The alternative hypothesis of the ore body, being a leached and replaced portion of some pre-existing rock, in this case the BHQ, appeared to be more realistic and adopted for determination of the ore bottom configuration. The ore bottom was out-lined by joining intersection on adjacent boreholes through smooth lines, though these lines may cut across the general dip of the formation.

21

5.2.3 Linear zones of oxidized rocks are most abundant in the iron horizon of syclined structure in the area. The deep seated zones, including several stratigraphic horizons, strike in parallel to host rocks (BHQ) and follows the principle trend of the structure; at depth they may plunge inconformity with folded and joint structures (Y.N.Belevtsev -High grade iron ores of Krivoyrog type, UNESCO 1973- Symposium 1970)

5.2.3 The remnant BHQ has been impersistent and traced over between north of

cross section S-9 and S-16 in the eastern corner and with the sinistral shift between S-10 and S-14.

5.2.4 Influence of each cross section has been taken up to half of the distance

between successive sections following the “rule of gradual change”. However, at the extreme end of the area of exploration (between S1-S1’ and S16-S16’) sectional influence up to buffer zone of mine lease area (7.5m from mine lease boundary) of 80m and 50m respectively has been considered.

5.3.0 ESTIMATION OF RESERVES AND GRADE 5.3.1 After delineating the limit of the ore zones (>45%) and boundaries of different

lithounits, geometry of the ore body have been demarcated and plotted on the respective cross sections. The sectional area of the ore zone has been computed by the software using Autocad. The strike influence of the section has also been computed using Autocad.

5.3.2 Ore resource tonnage has been estimated by multiplying the volume with the

tonnage factor of specific gravity of 3.50. The sum has been considered as geological in-situ resources.

5.3.3 Iron ore has been expected over a strike length of 1800m, wide area of 310m

to 570m. However, manganese ore is closely associated with the volcano- sedimentary rocks and occurs as lenticular intercalations in the top most levels ( Barama series- Guyana and lower Paramara-French Guyana and Suranam-B.Choubert,Directorate of Scientific Research France, UNESCO 1973- Symposium 1970). The UNFC code pertains to geological axis of (G1) have been assigned. The estimation of ore reserves at 45% Fe cut off is given in Table-4.

5.3.4 It reveals that the iron ore band extends over the strike length of 1800.00m

strike length in NW-SE with in the average wide area of 310m -570 m and upto the explored vertical depth 26.56m. However, the iron ore persists even beyond the explored depth as could be visualised from the geological cross section S-9, S-10, S-11,S-12 and S-14. A total of 9.880 m.t. of net reserves with average grade of 55.08% Fe, 6.42% SiO2 and 7.75% Al2O3 have been estimated.

22

`

Text Plate No. 2

25.74 57.99 2.80 6.96 Mineralized Zone of true thickness (m) with Grade (%) Fe, Sio2 Al2O3

Index

MSVR-13

MSVR-15

MSVR-27

MSVR-28RL. 767.11

RL.786.98

RL.750.95

RL.763.34

TD.30.00mTD.46.00m

TD.20.00m

TD.20.00m

750

700

RL. In Meters

S58°W

GEOLOGICAL CROSS SECTION ALONG SECTION LINE S9-S9'

R.F. 1:1000

N58°E

RL. In Meters

800

700

750

800BUFFER

ZONE LOW GRADE

IRON ORE

BUFFER

ZONE

SOIL/SCREE

FLOAT ORE

LIMON. CLAY

SOIL/SCREE

SOIL/SCREE

BHQ

BHQSOIL/SCREE

TYPICAL CROSS SECTION ALONG SECTION LINE S9-S9’

23

Table: No.4

SECTION-WISE, BOREHOLE-WISE, CATEGORY WISE ORE RESERVES/RESOURCES BY CROSS SECTION METHOD

Section

Number

Borehole

Number

Intersection

(m) Diff

(m)

True

Width

(m)

Average

Sectional

Influence

(m)

Area

(Sq. m)

(1)

Area

(Sq. m)

(2)

Reserves

(Tonnes)

(1)

Reserves

(Tonnes)

(2)

Total Reserves

(Tonnes)

Grade %

From To Fe SiO2 Al2O3

S6 MSVR-9 2.00 5.00 3.00 2.97 75.00 198.5999 94.5626 52330.5772 24917.0087 77247.5858 50.16 4.17 14.96

S9 MSVR- 13 2.00 17.00 15.00 14.85 73.00 1068.4387 0 274023.4350 0 274023.4350 48.51 1.98 20.78

MSVR- 15 0.00 26.00 26.00 25.74 73.00 1629.5310 0 417927.2821 0 417927.2821 57.99 2.80 6.96

S10 MSVR-14

0.00 11.00 11.00 10.89 97.50 1163.1883 246.7438 398446.3718 84521.2868 482967.6586 49.67 1.30 19.44

23.00 31.00 8.00 7.92 97.50 779.2334 250.3478 266923.8687 85755.8253 352679.6939 49.38 0.77 22.52

MSV-1 10.00 50.50 40.50 40.10 97.50 2244.2402 0 768757.1867 0 768757.1867 61.16 2.67 3.13

S11

MSVR-16 33.00 39.00 6.00 5.94 111.00 648.0432 0 252721.4894 0 252721.4894 45.35 29.41 1.78

MSVR-20

0.00 11.00 11.00 10.89 111.00 658.5835 0 256831.9566 0 256831.9566 52.91 8.61 9.98

29.00 59.00 30.00 29.70 111.00 2958.5030 2608.8463 1153746.0535 1017388.2273 2171134.2808 55.27 7.71 5.70

63.00 67.00 4.00 3.96 111.00 404.2944 448.4301 157665.2342 174877.1112 332542.3454 45.59 13.73 12.72

S12 MSV-2 1.50 45.00 43.50 43.07 99.00 4150.9092 3278.8272 1443755.5399 1140430.8566 2584186.3965 55.64 5.38 7.80

S13 MSV-18 0.00 8.00 8.00 7.92 69.00 837.4283 0 203007.4424 0 203007.4424 55.12 4.62 6.20

S15 MSVR-22 12.00 39.00 27.00 26.73 117.00 2685.5187 3125.2681 1103898.8433 1284660.5166 2388559.3599 57.60 7.06 4.61

42.00 47.00 5.00 4.95 117.00 446.2235 564.2446 183422.8916 231936.1847 415359.0764 53.19 6.86 8.77

Total 6933458.172 4044487.0172 10977945.1896 55.08 6.42 7.76

Geological In situ Reserves (Tonnes) 10977945.1896

55.08 6.42 7.75 Net Reserves

(Tonnes) 9880150.6707

(Million Tonnes) 9.880

24

CHAPTER-6 6.0.0 RELIABILITY OF ESTIMATION 6.1.0 FREQUENCY DISTRIBUTION 6.1.1 The entire primary sample data and sample data within the ore zone (>45% Fe)

have been subjected to statistical evaluation, the frequency distribution is highly skewed as could be seen from the Text Plate-3, 4, 5 and 6,7 & 8.

The statistical parameters estimated for primary sample data(1143 nos.) is as follows:

No. of Samples Fe2O3 % SiO2 % Al2O3 %

Mean 23.00 35.00 6.2

Variance 0.0009 0.007 0.033

Standard deviation 0.096 0.085 0.181

Sichel’s “T” estimator 1.000 1.030 1.010

The statistical parameters estimated for primary sample data (215 nos.) with in the ore zone is as follows:

No. of Samples Fe2O3 % SiO2 % Al2O3 %

Mean 55.00 8.40 5.00

Variance 0.0005 0.015 0.08

Standard deviation 0.0239 0.124 0.2896


6.2.0 ACCURACY OF ANALYTICAL PROCEDURE 6.2.1 Grade: The grade estimates of the deposit are based on the results of core

samples. Each sample undergoes the process of sample preparation and analysis. Since, sampling and analysis are two complimentary links of quality estimation chain, the possible source of errors, if any, could be from the bias in sample preparation and inaccuracies in assaying or both.

6.2.2 1143 nos. of samples pertaining to iron ore zones at 45% cut-off has been

plotted on to log probability graph for respective radicals of Fe2O3 , SiO2 and Al2O3 . The plots are provided as Text Plate-9, 10 and 11.

25

TEXT PLATE-3

TEXT PLATE-4

26

TEXT PLATE-5

27

1

80

10

20

30

40

6055

70

ß Ln(50)-Ln(23)

10090

Mean = 23

Lower Limit 0.9833

Upper Limit 1.017

Variance = 0.0009

Sichels 't' estimator 1.000

(at 90% Confidence Interval)

Standard Deviation 0.096

1

probabilityx2 log cycles

n = 1143

TEXT PLATE NO.6

50

45

35

25

15

1009080

70

605550

4540

35

30

25

20

15

10

DISTRIBUTION OF PRIMARY SAMPLES GRADE Fe

28

1

10

20

30

40

50

15

25

35

45

5560

70

8090

100


Mean = 35

1

20

30

40

50

25

35

45

5560

70

8090

100

41

DISTRIBUTION OF PRIMARY SAMPLES GRADE SiO2

TEXT PLATE NO.7


(at 90% Confidence

Interval)

Lower Limit 0.9852


Upper Limit 1.015

Variance = 0.007

n = 1143

29

Variance = 0.033

Upper Limit 1.023

Lower Limit 0.9773

(at 90% Confidence In terval)


1

20

10

30

50

40

60

908070

100

Mean = 6.2

n = 1143

20

10

30

50

40

60


908070

100

ß Ln(16)-Ln(6.2)

DISTRIBUTION OF PRIMARY SAMPLES GRADE Al2O3

TEXT PLATE NO.8


1

30

n = 215

Variance = 0.0005

Upper Limit 1.007

Standard Deviation

0.0239

Lower Limit 0.9927

(at 90% Confidence

Interval)Sichels 't' estimator 1.000

1

10

20

30

40

50

1

10

20

30

40

50

Fe %

Valu

e

1 1

10

20

40

50

10

20

30

40

50

probability x2 log cycles

Mean = 55

DISTRIBUTION OF PRIMARY SAMPLES GRADE (ZONE DATA) Fe2O3

TEXT PLATE NO.9

70

31

5045

30

20

n = 215

Variance = 0.015

Upper Limit 1.019


Lower Limit 0.9817

(at 90% Confidence

Interval)Sichels 't' estimator 1.010

10090

80

70

6065

40

35

30

5045

30

20

10

1

10090

80

70

6065

40

35

30

Mean = 8.4

10

1

25

15

SiO2 ZONE DATA probabilityx2 log cycles

DISTRIBUTION OF PRIMARY SAMPLES GRADE (ZONE DATA) SiO2

TEXT PLATE No.10

32


(at 90% Confidence

Interval)

Lower Limit 0.9701

Standard Deviation

0.2896

Upper Limit 1.031

Variance = 0.08

n = 215

1

10

20

30

40

50

1

10

20

30

40

50

TEXT PLATE NO.11


Mean = 5

DISTRIBUTION OF PRIMARY SAMPLES GRADE (ZONE DATA) Al2O3

33

6.2.3 Comparative study on statistical parameters

On comparing with the values obtained on various parameters, it has been found that the grades are more congruent. Hence, the analytical values are more reliable.

Between S1-S16 Fe2O3 % SiO2 % Al2O3 %

Statistical Method 55.00 8.40 5.00

Calculated 55.08 6.42 7.75


34

CHAPTER-7

7.0.0 CONCLUSIONS AND RECOMMENDATIONS 7.1.0 CONCLUSIONS 7.1.1 M/s Srinivasalu Mine Lease area (ML No.2631) falls in the Hiriyur range,

Longitude E76º26’24.31” and 76º26’27.72” and Latitudes N13º43’08.39” and 13º43’04.00”, which is approachable by road from Hiriur at a distance of 39km. The railway station is in Hosadurga on Bengaluru-Harihar broad-gauge line of SWR.

7.1.2 The Chitradurga Schist Belt extends over a strike length about 450 km

Chikkanahalli in the north and Yerrahalli in the south covering 5550 Sq.km. The area is covered in Survey of India Toposheet Nos.57 C/6. Copper has been exploited by HGML at Ingaldal near Chitradurga.

7.1.3 The average depth of the mineralised zone proved by the present exploration in

the present mine lease area is 26.56 m over 1800m strike length. However, full thickness of the iron ore band has been not fully encountered as could be visualized from the cross section S12 and S10 The maximum ore has been intersected is 43.07m (MSV-02).

7.1.4 The rocks exposed are typical iron formations with the limonitic ore, haematitic

ore, low grade iron ore, clayey iron ore and siliceous ore of Vani Vilas Formations. The predominant ore minerals are hematite and limonite and goethite to some extent. The important non ore consists of remnants of limonitic clay, clay and banded haematite quartzite.

7.1.5 Generally, the iron ore ranges from haematitic ore to laminated, powdery and

siliceous ores have also been encountered. 7.1.6 Based on the reserves/resource estimation by geological cross section, the net

in-situ reserves of 9.880 m.t. of iron ore with 55.08% Fe, 6.42% SiO2 and 7.75% Al2O3 at 45% Fe cut off has been estimated. The overall ratio of SiO2: Al2O3 is 1.80.

7.2.0 RECOMMENDATION 7.2.1 M/s Srinivasalu Mine lease Area [ML No.2631] has good potential which would

be amenable to systematic scientific mining. The limestone has been encountered in the boreholes MSVR-10 and MSVR-11 is of moderately good quality, which could be used for manufacture of cement. The ochre, which has been traced in the southeastern and south-western part of the lease area between S-14 and S-16, is of good quality which could be used in the pigment industry.

35

References :

1 Document on strategy for exploration, exploitation and development for Iron Ore in India.

Sub group on Iron Ore, Government of India, MOM.

Jan-2006

2 Preliminary appraisal of the Ballari Hospet Iron Ore Deposits, Ballari Division, Mysore.

K.Ganeshan & R.C. Vidyarthi, IBM, Nagpur.

March-1964

3 Archaean Greenstone belts of South India

B.P.Radhakrishna M.Ramakrishnan

Geological Society of India, Bengaluru, 1990

4 Geology of Karnataka BP Radhakrishna R.Vaidyanathan

Geological Society of India

5 Computing reserves of Mineral deposits : Principles and Conventional methods

Constantine C.Popff

USBM, 1965

6 Economic Mineral Deposits Revised Edition

Mead L.Jensen & Alan M.Bateman

John liley & Sons New York 1951

7 Economic Evaluation of Mineral Property

Sam L. Vanlandangham

Huchinson Press Publishing Co. Pennsylvania 1983

8 Geo-statistical Ore Reserve Estimation

M. David Elsevier Scientific Publishing Co. Netherlands, 1977

9 Exploration Report Far Eastern section BRH Iron Ore Mine, Dist. Ballari, Karnataka

MECL, Sept, 1996

10 Exploration Report Bailadila Iron Ore Deposit No.4

NMDC, Hyderabad, Andhra Pradesh

11 Exploration Report Rowghat Iron Ore Deposit ‘F’,Block-A Phase-I, Dist. Bastar, Madhya Pradesh

MECL, Dec, 1991

12 Exploration Report Chiria Iron Ore Deposit, Phase-I, Dist. Singhbhum, Bihar

MECL, March, 1974

13 Vision 2020 IBM 14 Mineral Year Book 2012 IBM 15 Special Issue on Iron Ore

Future- Next Decade Journal of Mines, Metals & Fuels

Mar/Apr-2010

36

PERSONNEL ASSOCIATED

1. Overall Guidance

Shri S.K. Thakur General Manager (Exploration)

2. Monitoring and Co-ordination

Shri S.K. Thakur

Shri D.Mohan

General Manager (Exploration)

Sr. Manager(Geology)

3. Physical Execution of work

Shri P.Sekar

Shri Sandeep Sarangi

Shri A.K. Ghosh

Shri S.N. Dhyani

H.R.Mallick

Gasal Khan

Sr. Manager(Geology)

Officer Trainee (Geology)

ASMO

ASMO

Sr. Survey &Map Officer

Sr. Drilling Engineer

4.

5.

Geological Mapping

Shri S. Satpathy Sr. Geologist

Data Processing & Documentation

Dr. S. Kamalakaram

Shri J. Narayana Moorthy

Shri Akhil Kumar Dwivedi

Sr. Manager (Geology)


O.T.(Geology)

6. Chemical Laboratory, MECL, Nagpur

Shri PC Khot

Manager (Lab.)

7. Petrological Laboratory, MECL, Nagpur

Shri Sayantan Pal

Dr. Anjani Kumar

Geologist


8. IT Centre

Shri ADP Rao

Shri B. Umapathy

Shri K.K. Kaushik

Shri Rahul Mathankar

Shri Philip Varghese

Shri S.Unnikrishnan

Shri N.C.S.Reddy

Sr. Manager (Systems)

Sr.Manager (Geology)

Sr.Manager (Geology)

Sr. Programmer(Systems)

Sr. Console Operator

Jr. Console Operator

Jr. Console Operator

limonitic ore exhibiting folds a mini-ratna company · 2019-02-15 · m/s srinivasalu mine lease...

Documents