singhbhum

CHAPTER 1

Introduction

1.1 Introduction

Technological improvements in integrated application of multi-spectral remote

sensing and geophysical techniques, using Geographical Information System (GIS), are

providing opportunities for acquiring ever-increasing volumes of data as well as powerful

analytical techniques for deriving potential geological information.

Remote sensing, both aircraft-borne and satellite-borne, has emerged as a

powerful tool for data acquisition of the earth resources. The different objects on earth’s

surface can be mapped using sensors on board aircrafts and spacecrafts. The sensors used

in remote sensing techniques include a variety of sophisticated systems, viz.,

photographic cameras, and different types of optomechanical multispectral scanners,

pushbroom scanners, microwave radiometer and imaging radars. The main advantages of

remote sensing are: synoptic coverage, repetitive coverage, multispectral approach

(visible, infrared, thermal and microwave remote sensing), geometric accuracy of data,

feasibility, quantification and computer compatibility, multidisciplinary approach, time

and manpower saving, repeatability of results, overall low cost-to-benefit ratio, and real

time continuous data.

Gravity anomalies have become an important tool for geologic studies since the

widespread use of high-precision gravimeters after the Second World War. Recently the

development of instrumentation for airborne gravity observations, procedures for

acquiring data from satellite platforms, the readily available Global Positioning System

with precise vertical and horizontal control, improved global databases, and enhancement

Chapter 1 Introduction

2

of computational hardware and software have accelerated the use of the gravity method

in traditional as well as new geologic studies (Hackney and Featherstone, 2003; Fairhead

et al., 2003; Featherstone and Dentith, 1997; LaFehr, 1991; Majumdar et al., 1984 and

1998; Li and Götze, 2001; Kamguia et al., 2005, North American Gravity Database

Committee, 2005; Rajesh and Majumdar, 2004; Majumdar and Bhattacharyya, 2005;

Majumdar et al., 2006, Chatterjee at al., 2007)

1.2 Study Area

The present study area of about 6000 sq. km, is a part of Singhbhum Orissa-

Craton, located in the eastern part of the Indian subcontinent; it lies between latitudes 200

50' N and 230 24' N and longitudes 840 56' E and 870 5' E. The area is a hard rock terrain

comprising of granites, gneisses, quartzites, shales and phyllites. It is one of the

geologically complex and mineralogically rich regions of India, and has undergone

several phases of tectonic deformation, metamorphism and metasomatism leading to

formation of a sheared zone, known as Singbhum Shear Zone (SSZ). This SSZ is host to

occurrence of large number of important mineral deposits. The present area of interest

covers parts of three adjoining States of India, namely, Jharkhand, Orissa and West

Bengal and falls in the Survey of India Toposheets (Numbers 73E, 73F, 73G, 73I, 73J,

and 73K). The location of present study area is shown in Fig. 1.1.

1.3 General characteristics of the study area 1.3.1 Location and approach

The major cities/township in and around the study area are Jamshedpur,

Chakradharpur, Chaibasa, Monaharpur, Bhagmundi, Noamundi, Champua,

Keonjhargarh, Sukinda, Harichandanpur, Satkosia, Jashipur, Badampahar, Baripada,

Baharagora, Mosabani, and Rakha. The places are easily approachable by road and rail

from all parts of the country. National Highways (NH) 5, 6, 32 and 33 passess through

different parts of the study area. The area is well connected by south-eastern rail lines of

India.


3

Figure 1.1 Location map of the study area


4

1.3.2 Climate

The climate of the area is tropical with hot and dry summer and pleasant winter.

The summer falls in the months of April to June, while winter is from November to

March. The southwest monsoon is the principal source of rainfall during July to August.

Average temperatures range from 8°C (winter) to 47°C (summer) with average yearly

rainfall of about 1300 mm.

1.3.3 Topography, soil and drainage

There are distinct chains of hills occurring in the northern, central and southern

part of the study area, rising to a maximum height of 1500ft at several places. In the

northern part (around Dalma Volcanic), the hills and valleys are covered with dense

forests, and are protected as ‘reserved forest’. The plateau between Dalma Volcanic and

Singhbhum Shear Zone is covered with thick literate. On the hillsides of Dhanjori Group

and Kolhan Group, which occur south of SSZ up to central plateau, forests have been

much degraded. The hills fringing the central plateau are granitic in nature and covered

with a few small trees or are completely barren. A chain of hillocks composed of

dolerites, forms dykes criss-crossing the plateau. The boulders are exposed on the

hillocks. The thin soils on the plain lands have scrubs and bushes. Simlipal, occurring in

south-eastern part of the study area, is protected as ‘reserved forest’. Cultivated fields

surrounding isolated villages, which are located mostly near the roads and rail lines,

occupy the major part of the plateau. The principal rivers are Subarnarekha, Brahmani,

Baitarani, Burhabalang and Koel.

1.4 Geological setup

Extensive work has been carried out for geological assessment in this part of the Indian

Shield that has contributed to the unveiling of many of the complexities (Dunn, 1929,

1937; Dunn and Dey, 1942; Sarkar and Saha, 1962, 1963; Naha, 1965; Mukhopadhayay

et al., 1975; Sarkar and Saha, 1977; Acharya, 1984; Ghosh and Sengupta, 1990). Initially,


5

there were dual concepts regarding the stratigraphic and tectonic classifications of this

region. According to one, the rocks of north and south Singhbhum, in spite of their

structural and metamorphic contrasts, belong to one broad stratigraphic unit; whereas, the

other concept was that the rocks of north and south Singhbhum two separate stratigraphic

and orogenic belts. Both opinions believe that the structural and metamorphic contrast of

north and south Singhbhum were brought about by large-scale horizontal displacement of

the rocks along a prominent E-W thrust belt.

Dunn (1929) and Dunn and Dey (1942) classified the Precambrian rocks of

Singhbhum into following divisions:

Iron Ore Stage

Iron ore Series

Chaibasa Stage

According to them, the rocks of north Singhbhum belong to both stages and those of

south Singhbhum to the Iron Ore Stage only. The rocks of north have an E-W regional

strike and consist of medium to high grade metamorphic rocks, whereas those of south

are characterized by NNE –SSW regional strike and low grade regional metamorphism.

The juxtaposition of these rocks as explained by them was prominent thrust, named

“Copper Belt Thrust” which stretches for about 200 km. The thrust plane have an over all

northerly dip, but regionally they form a sweeping curve, convex towards north.

Sarkar and Saha (1977) and Sarkar et al. (1979) have suggested a revised

stratigraphic sequence of Singhbhum (Table1.1) on the basis of some key areas and a

critical review of earlier records, coupled with geochronology data (Sarkar and Saha,

1962, 1977; Sarkar, 1980). In this revised correlation, the rocks of north Singhbhum, i.e.,

the “Singhbhum Group ” and “Dalma Volcanic” are placed much younger than the “Iron

Ore Group”, i.e., rocks of south Singhbhum; both evolving into two separate orogenic

belts (closing at 850 ma and 2900-3000 ma respectively). According to Sarkar (1963)

large-scale N-S displacements of the rocks along the thrust belt have brought these two

orogenic belts in an intersecting disposition.


6

Bhattacharya (1966) carried out structural study in the Chakradharpur area in

western Singhbhum ("Copper Belt Thrust" of the earlier workers) and within the area of

the so-called intersection of the two orogenic belts. He concluded that the NNE trend of

the rocks of the area corresponds to the strike of the axial plane schistosity of an earlier

- - - - -- - --Unconformity - - - - - - - - - - -

Table 1.1 Stratigraphic sequence of Precambrian rocks of Singhbhum after Sarkar and Saha (1977) and Sarkar et al. (1979)


7

set of folds, and the E-W trend (more precisely ENE-WSW) to that of the axial plane

schistosity of a later set of folds; the latter being overprinted on the former.

These studies have revealed that a Shear Zone named as Singhbhum Shear Zone

(SSZ) occurs as a curvilinear belt with an E-W trend. Singhbhum rocks, like those of

other Precambrian terrains, have undergone many phases of deformation and

metamorphism. Rocks to the south of the Singhbhum Shear Zone are relatively less

metamorphosed compared to those to the north. The basement of the Singhbhum

metasedimentary rocks can be traced in a broadly elliptical pattern of granitoids,

surrounded by metasediments and metavolcanics of Greenstone Belt association. Most of

the intrusive rocks in the area are Singhbhum Granodiorite intruded during 3.1 Ga, (Saha,

1994) and were crosscut in rectangular pattern by voluminous Neoarchaean mafic and

ultramafic dike swarms (Roy et al., 2002). Rocks of Older Metamorphic Group (OMG)

form the basement rocks. They are exposed in the central part of the basin. A primeval

nucleus to the Singhbhum Granite was built by the relatively small remnant of the OMG

and Older Metamorphic Tonalite Gneiss (OMTG) rocks, between 3.4 and 3.5 Ga and

metamorphosed to amphibolite facies (Sharma et al., 1994; Saha, 1994). The Singhbhum

Granodiorite is intrusive into these old rocks and to younger, mid Archaean

metasediments, at upper greenschist facies, including iron formations, schists and

metaquartzites and siliciclastics of the Iron Ore Group (IOG). OMG mainly consists of

schist. The IOG rocks overlie the basement rocks and are exposed over vast areas in the

western part and over some areas in the east. The IOG succession is believed to have

formed a broad NNE plunging synclinorium with overturned western limb. The

succession has a symmetric lithology with the Banded Iron Formation (BIF) lying in the

middle of the succession bounded on the upper and lower sides by phyllite and basaltic

lava. Massive batholiths of granite to granodiorite composition are occupying vast areas

in the central part to the south of SSZ. This granitic mass was emplaced after the

deformation of the IOG. Xenoliths of older IOG and OMG rocks are found within the

granitic mass. Radiometric dating suggests an age of 2950 Ma for Singhbhum

Granite. Rocks of Dhanjori Formation (Mazumder, 2005), which were initially classified

as belonging to Dhanjori Group (Saha, 1994 and GSI, 1998), are exposed in the eastern


8

part of Singhbhum region. This palaeoproterozoic Formation/Group consisting of

conglomerate, arkose, quartzite and lava flows, overlies the Singhbhum granite and, is in

turn, overlain by the Chaibasa and Dhalbhum Formations constituting the Singhbhum

Group (Mazumder, 2005) to the north of Singhbhum Shear Zone. The Dhanjori

Formation/ Group of 2100 Ma (Roy et al., 2002) includes lavas in its upper part. To the

north, the Dhalbhum Formation comprising quartzites and schists; is followed by Dalma

Formation (Mazumder, 2005), which were initially classified as Dalma Volcanic (Saha,

1994 and GSI, 1998), consisting of lava and volcaniclastic rocks of 1600 Ma (Roy et al.,

2002b). Chandil Formation of 1500 Ma (Sengupta and Mukhopadhaya, 2000) and

comprising of quartzites, mica schists, carbonaceous phyllite, weakly metamorphosed

acidic volcanic and volcaniclastic rocks, lies between Dalma Formation/ Volanic and

Chottanagpur Granite-Gneiss (CGG). Dolerite dikes have intruded in the Singhbhum

Granite and occur mostly in southern part of Singhbhum. Kolhan Group occurs to the

SSW of SSZ. It consists of gently dipping purple sandstones, conglomerates, limestones

and slates of Proterozoic age.

The entire metasedimentary succession thus may cover more than 500 million

years of supracrustal sedimentation history and believed to have suffered from severe

thrusting and multiphase folding and metamorphism. The rocks were thrusted towards the

craton core, along the prominent and laterally extensive semi-circular Singhbhum Shear

Zone (SSZ), which encompasses mainly Dhanjori quartzites and schists and can be

followed for some 200km along strike and for few km in width. Sedimentary structures,

in many cases, can be easily recognized on the weathered bedding surfaces in mixed

pelitic and arenitic rocks, but are not recognizable in the formerly massive pelites that

were turned to almandine-mica lustrous schists, displaying schistosity and crenulation

cleavage. Conspicuously, the degree of metamorphism decreases markedly towards the

top of the section and is much lower in the Dalma and Chandil Formations, probably

reaching lower greenschist facies at the top. The timing of one of the metamorphic events

is around of 1600 Ma, as is the age of the shearing/ thrusting along the Singhbhum Shear

Zone (Krishna Rao et al., 1979; Sengupta and Mukhopadhaya, 2000).


9

Moreover, former researcher identified three distinct petrotectonic zones in the

Singhbhum crustal province (Bose and Chakraborty, 1994; Sarkar et al., 1992; Blackburn

and Srivastava, 1994). From south to north, these are: (1) the southern Archaean granite–

greenstone terrain (Acharyya, 1993; Sengupta et al., 1997), widely referred to as the

“Singhbhum Granite Craton”; (2) the almost 200 km long North Singhbhum Fold Belt

(NSFB) comprising the Dhanjori, Chaibasa, Dhalbhum, Dalma and Chandil Formations

(Mazumder, 2005), and (3) the extensive granite-gneiss and migmatite terrain in the

north, known as the Chottanagpur Granite-Gneiss (CGG). A zone of sheared and

deformed rocks known as Singhbhum Shear Zone, SSZ (Mazumder, 2005) build up close

to the contact of the oldest Proterozoic supracrustal (Dhanjori) belt with the Archaean

nucleus. Contradicting the previous interpretation (Sarkar and Saha, 1962; Saha, 1994), it

has been established that the SSZ does not mark the boundary between the Singhbhum

Archaean nucleus and Proterozoic NSFB (Blackburn and Srivastava, 1994). Recent

studies establish that the Singhbhum Group of rocks (the Chaibasa and Dhalbhum

Formations, Sarkar and Saha, 1962) and the Dhanjoris suffered a prominent

metamorphism around 1600 Ma (Acharyya, 2003). Quadrangle geological map

(lithological map) of Geological Society of India (1998) over the study area is shown in

Fig. 1.2(a) and the geological map (regional lithological map) of Saha (1994) is shown in

figure 1.2(b).

1.5 Mineral occurrences

This region is one of the highly mineralized regions of India having rich deposits

of iron, copper, uranium and manganese ores with traces of other ores also. The ore

deposits of the Singhbhum Shear Zone (SSZ) in the study area have been mobilized from

the volcanogenic rocks of that zone by albite-rich metasomatic fluids permeating through

them. The fluids themselves become enriched in Fe, Mg, Ca, Co, Ni, Cr, V, Mn, Ti, and

H2O. Thus enriched in basic elements and water, these fluids gave rise to zones of

biotitozonation, chloritization, and sericitization around the soda-granite bodies within

which copper, uranium and apatite-magnetite ore deposits formed (Gangopadhyay and

Samanta, 1984). The ore bodies are mainly restricted to one persistent stratigraphic


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Figure 1.2a Geological map of the study area (after Geological Survey of India, 1998)


11

Figure1.2b Geological map of the study area (after Saha 1994). 1-Older Metamorphic Group; 2-Older Metamorphic Tonalite-gneiss; 3-Pala Lahara Gneiss; 4-Singhbhum Granite-Phase-I; 5-Singhbhum Granite-Phase-II and xenolith-dominated areas of Bonai Granite; 6-Nilgiri Granite; 7-Iron Ore Group lavas, ultramafics; 8-Iron Ore Group shales, tuffs, phyllites; 9-BHJ, BHQ and sandstone-conglomerate of Iron Ore Group; 10-Singhbhum Granite –Phase-III, Bonai Granite, Chakradharpur Granite; 11(a)-Singhbhum Group pelites, 11(b)-mafic bodis 11(c)-carbon phyllite; 12-Singhbhum Group quartzites; 13-Dhanjori Group(unclassified); 14-Quarzite-conglomerate-pelite of Dhanjori Group; 15-Dhanjari-Simlipal-Jagannathpur-Malangtoli lavas; 16-Dalma Lavas; 17-Proterozoic Gabbro-anorthosite-ultramafics; 18-Kolhan Group and equivalents 19-Mayurbanj Granite; 20-Soda granite, Arkasani Granite, Kuilapal Granite, alkaline granite; 21-Charnockite; 22-Khondalite; 23-Amphibolite enclaves (within CGG) 24-pelitic enclaves within CGG; 25-Chhotanagpur granite-gneiss(CGG); 26-Porphyritic member of CGG; 27-Gondwana sediments 28-Alluvium, Tertiaries.


12

horizon called the “granular rock” (quartz-chlorite-biotite schist). Over the study area,

the copper mineralization occurs as number of parallel to sub-parallel discontinuous lodes

along the major tectonic grains of the area. The sulphide mineralization is considered to

be associated mainly with the meta-volcanics and meta-tuff of Singhbhum and Dhanjori

Groups. Predominant sulphide minerals are chalcopyrite, pyrite and pyrrhotite. The mode

of occurrence varies from massive to braided veins, stringers, and disseminations,

discordant to sheet like bodies and also as en-echelon veins. Sarkar et al. (1986)

suggested that sulphide mineralization in this belt is confined mainly within certain

stratigraphic horizon adjacent to the Dhanjori metavolcanics. The remobilization has

mainly taken place along shear bands and concentrated during the later metamorphic

process. Clay minerals consisting of serisite, mica-feldspars derived clay minerals, iron

ores consisting of magnetite, hematite and copper ore consisting of chalcopyrite,

chalcocite were also reported by Saha (1984; 1994). A major copper mineral,

chalcopyrite occurs as veins, patches and disseminations, mainly in chlorite schist in the

Singhbhum Shear Zone. Apatite mineralisation is found along the Singhbhum Shear Zone

over a length of 60 km as veins and lenses in biotite-clorite rock. Asbestos minerals are

entirely confined to the basic and ultrabasic rocks of IOG and Dalma Volcanic. Gold

bearing quartz veins and iron ore consisting mainly banded hematite quartzite are

reported from number of locations Manganese occurrences are found in the form of thin

beds, lenses and concentration in the schist and quartzite of Dalma Volcanic (Geological

Survey of India, 1999).

1.6 Review of literature

The extensive scope of remote sensing application in topographic structural

mapping are proved by various researchers (Sarkar and Chakraborti, 1982; Harris, 1984;

Parson and Yearley, 1986; Majumdar and Bhattacharya, 1988; Masuoka et al., 1988;

Verma, 1991; Javed et. al., 1993; Karpuz et al., 1993; Majumdar, 1995; Mah et al., 1995;

Briere, and Scanlan, 2000; Majumdar and Mohanty, 1999; Sharma et al., 1999; Robinson

et al., 1999; McGregor et al., 1999; Rivard et al., 1999; Chernicoff, 2002; Paganelli et al.,

2003; Singhroy and Molch, 2004).


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The lithological mapping in scarcely vegetated areas have become possible since

the beginning of multiple and narrow-band spectrometers in the visible and / or infrared

region of the electromagnetic spectrum; whereas, geo-botanical techniques based on the

spectral response of plants are useful for lithological mapping in highly vegetated areas.

These techniques allow for detection of structural and taxonomic variations, which can be

related to the subsoil (Weber, 1985). Integrated remote sensing and GIS has been found

to be a very effective tool for geological mapping/lithology discrimination by several

researchers (Seigal and Abrams, 1976; Seigal and Goetz, 1977; Hunt, 1979; Marsh and

Mckeon, 1983; Chang and Collins, 1983; Weber, 1985; Yuna et al., 1998; Loughlin,

1991; Price, 1999; Saraf, 1999; Briere and Scanlan, 2000; Grunsky, 2002).

Remote sensing as a technology started with the aerial photographs in the late

nineteenth century. Satellite remote sensing originated in the space age during late

twentieth century with launch of Landsat satellite in 1972. In the very early stages,

satellite imagery were mostly analyzed by visual interpretation techniques following the

techniques used for aerial photographs, namely, the photo-geologic elements, tone, size,

shape, texture, pattern, shadow, site and association. However, with the availability of

much faster and superior computers and more developed digital processing techniques,

there has been an explosion in processing of digital satellite remote sensing data. In

satellite remote sensing technology, sensors mounted on the satellite record the

electromagnetic radiation either in the visible, infrared, thermal or microwave parts of the

spectrum. At present, a wide variety of satellite imagery using different sensors are

readily available of which Landsat MSS, Landsat TM, SPOT, IRS LISS, IKONOS,

ASTER, ERS-1/2, JERS-1, RADARSAT, SAR and SRTM are widely used. Landsat

MSS sensor has three spectral bands in visible and one near infrared parts (NIR) of the

electromagnetic spectrum with 80 m spatial resolution, while Landsat TM has seven

bands of which three are in visible, one in NIR and two in middle IR each of 30 m spatial

resolution and one thermal band with spatial resolution of 120 m. The last of Landsat

series of satellites, Landsat-7 ETM+ is similar to the earlier TM, but with an additional

15-m resolution panchromatic band, and improved resolution (60m) for the thermal band.


14

SPOT and IRS satellites with higher spatial resolution of 10m and 23.5m respectively,

also have the capability of stereo viewing. IRS LISS sensors capture radiation in blue,

green, red and IR bands at 23.5m spatial resolutions, it also provides 5.8m resolution

panchromatic image as well as 188m resolution wide field sensor (WiFS) imagery.

Advancement in remote sensing techniques and satellite digital image processing has

been discussed in several standard textbooks and numerous journal articles by several

authors. Some of the standard research literature are: Vincent and Thomson (1972),

Gonzalez and Woods (1992), Castleman (1979), Moik (1980), Cracknell (1982) Hord

(1982), Simonet (1983), Atkinson et al (1985), Curran (1985), Jensen (1986), Mather

(1987), Sabins (1997), Paine and Lodwick (1989), Eliason and McEwan (1990), Light

(1990), Gupta (1991), Drury (1993), Jensen (1995), Nayak et al.(1996), Foresman et

al.(1997), Vincent (1997), Nayak et al. (2001), Singh at al.(2002), Sahoo et al. (2005),

Verbyla (1995), Campbell (1996), Saraf and Choudhury (1997, 1998) Cracknell (1997),

Conway (1997), Schmid et al.(2005), Choudhury et al.(2006), Koch et al.(2008). While

this new space-driven approach has not yet revolutionalized the way in which the

geoscientist conduct their field studies, it has proven to be an indispensable technique for

improving the geological mapping process and carrying out practical exploration for

mineral and water resources in a cost-effective manner.

In recent years, GIS has been widely used for the integration and comparative

study of multiple dataset, viz., remote sensing dataset, geological dataset, geophysical

dataset and other collateral dataset for extensive geological study, structural mapping,

and ground water and mineral potential mapping. A major function of a GIS is the ability

to analyze the spatial relationships between different dataset. Integrated study using

remote sensing data, geological and geophysical data has been successfully applied in

geological studies by various scientists (Ilyin et al., 1983; Bhattarai, 1983; Rakshit and

Swaminathan, 1985; Schlichter and Kuhlmann, 1986; Tsombos and Kalogeropoulos,

1990; Rabie and Ammar, 1990; Hs and Ruhland, 1990; Ishiwada and Akiyama; 1992;

Huadong and Pinliang, 1992; Bonnefoy et al., 1992; Thomson and Salisbury, 1993;

Kruse, et al., 1993; Bonham-Carter, 1994; An et al., 1995; Sabins, 1999; Rivard et al.,

1999; Cudahy et al., 1999; McGregor et al., 1999; Srivastav et al, 2000; Verma, 2000;


15

Zumsprekel and Prinz, 2000; Lunden et al., 2001; Chernicoff et al., 2002; Srivastava,

2005; Pradhan et al., 2006; Pena and Abdelsalam, 2006; Srivastava and Bhattacharya,

2006).

Some work had been carried out in the study area for structural study and mineral

potential mapping using remote sensing involving Landsat TM data and GIS (Sarkar,

1982; Rakshit, 1985; Parson, 1986; Chetty, 1993; Javed, 1993; Majumdar, 1995 and

1998; Mukhopadhyay et al., 2002).

1.7 Scope of present study

It is one of the geologically complex and mineralogically rich regions of India,

and has undergone several phases of tectonic deformation, metamorphism and

metasomatism leading to formation of a sheared zone, known as Singbhum Shear Zone

(SSZ). This SSZ is host to occurrence of large number of important mineral deposits.

Since very limited work using integrated study of remote sensing (IRS and Landsat) and

GIS for structural mapping and mineral potential mapping of the study area has been

reported, the present study was undertaken with the aim of comprehensive geological

appraisal involving structural mapping, lithological mapping, mineral occurrence

mapping through a GIS based integrated study of remote sensing (multi-sensor satellite

image) and gravity data.

1.8 Objectives of the present study

The primary objective of the present study was to undertake a geological appraisal

over a part of Singhbhum-Orissa Craton, India through an integrated remote sensing,

gravity and GIS approach. The aim of the study was to generate lithological, structural

and mineral maps. The following tasks have been carried out to achieve the objective of

the present investigation:

• To delineate structural features and generate computer automated lineament

pattern for understanding tectonic activities through visual interpretation of


16

synthetic aperture radar data, ESR-1 SAR and digitally enhanced (using Fast

Fourier Transform technique) ERS-2 SAR.

• To construct a lithology map using merged image formed by fusion (using

Principal Component Analysis technique) of optical (IRS-1 C LISS-III) and

synthetic aperture radar (ERS-2 SAR) data and to carry out comparative

assessment analysis between inferred and published lithology maps using GIS.

• To construct lithology maps based on estimated relative emissivities (using

Reference Channel, Emissivity Normalization and Alpha Residual methods) and

land surface temperature (using Reference Channel and Emissivity Normalization

methods) from MODIS thermal infrared (TIR) data, and to carry out comparative

assessment analysis between inferred and published lithology maps.

• To generate mineral map using Advanced Spectral Analysis techniques from

Landsat ETM+ data.

• To generate Digitized Gravity Model (DGM) from Bouguer Gravity anomaly map

using GIS technique, and to prepare aspect map for delineation of gravity

lineaments to infer subsurface geology.

1.9 Data used

Following data were used in the present study:

1. Survey of India (SOI) Topographic Maps: Nos.73E, 73F, 73G, 73I, 73J, and 73K

on 1:250,000 scale and Nos. 73J/6, 73 J/1, 73 J/2, 73 J/3, 73 J/5, 73 J/6, 73 J/7, 73

J/9, 73 J/10 and 73 J/11 on 1:50,000 scale

2. Geological Quadrangle Map (Lithological map) No.73 J on 1:250,000 scale,

Geological Survey of India (1998)

3. Geological map (regional lithological map) of Singhbhum-Orissa Craton region

compiled by Saha (1994) on 1:700, 000 scales.

4. Mineral map of India published, 1999 on 1:5,000,000 scale

5. ERS-1 SAR Path Radiance Image (PRI)/Precision Image; path-P 0842 / row-S

0198, 10th August 1993.


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6. ERS-2 SAR Path Radiance image (PRI)/Precision Image; path-0842/row-0198,

30th September 2002

7. IRS-1C LISS-III image; path-106/row-56, 11th April 2002.

8. Landsat -7 ETM+ image; parts of paths/rows-140/44, 139/44, 140/45 and 139/45,

7th May 2003.

9. MODIS (Level 1B), MOD021KM; Gring Point Latitude: 33.6621, 30.1393,

12.7151, 15.8116, Gring Point Longitude: 74.168, 98.5028, 92.8111, 71.5094; 7th

May 2003

10. All India Weather Bulletin; 8th May 2003.

11. Bouguer Gravity Anomaly Map of Singhbhum region (Verma, et al., 1984)

1.10 Methodology

The following methodology was adopted and represented in flow chart (Fig. 1.3)

The following methodologies have been followed:

1. ERS-1 SAR image has been visually interpreted for identifying lineaments and

Rose diagram has been generated from these delineated lineaments.

2. ERS-2 SAR image has been enhanced by Fast Fourier Transform (FFT)

technique.

3. The FFT enhanced ERS-2 SAR image has also been visually interpreted for

identifying lineaments and Rose diagram has been generated from these

delineated lineaments.

4. A computer programme (‘C’ language) has been developed for extraction of

strike directions of lineaments, which have been used in the generation of Rose

diagrams.

5. Two merged images have been formed by fusion of optical (IRS-1C LISS III) and

synthetic aperture radar (ERS-2 SAR) data, using Principal Component Analysis

(PCA) technique; i) One has been generated by fusing histogram equalization

enhanced IRS-1C LISS III and FFT enhanced ERS-2 SAR image (named as

FFT1C); and ii) another by fusing histogram equalization enhanced IRS-1C LISS

III and Frost filtering enhanced ERS-2 SAR image (named as FF1C).


18

Figure 1.3 Flow diagram represents the methodology of the present study

6. Feature-oriented Principal Components Selection (FPCS) technique has been

applied to generate FCC images from the fused images, and lithological maps

have been finally prepared from the two FCC images.


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7. GIS technique has been used for change detection analysis between the fusion

based inferred and published lithological maps.

8. Reference Channel, Emissivity Normalization and Alpha Residual methods have

been applied to estimate relative emissivities, while land surface temperatures

have been estimated using Reference Channel and Emissivity Normalization

methods. MODIS TIR data has been utilized for both the estimations.

9. Lithology maps (MOD-MAP) have been prepared based on the estimated relative

emissivities and land surface temperatures. Change detection analysis has been

carried out between the inferred and published lithological maps.

10. Landsat ETM+ data has been analyzed by means of Advanced Spectral Analysis

techniques for mapping of probable mineral occurrences.

11. Landsat ETM+ data has been converted to radiance and then to reflectance values.

Atmospheric correction has been applied to the reflectance value using Dark

Subtraction technique.

12. Minimum Noise Fraction (MNF) transformation has been carried out to segregate

the noise in the data and to determine the inherent dimensionality of image data.

13. Pixel Purity Index (PPI) has been calculated to find purest pixels in the image,

and N-Dimensional visualization has been applied to delineate the segregated

corner pixel cloud.

14. The endmember spectra have been extracted by averaging the segregated corner

pixel cloud.

15. Three techniques, namely Spectral Feature Fitting (SFF), Spectral Angle Mapper

(SAM) and Binary Encoding (BE) have been used for identification of the

extracted endmember spectra, and Mixture-Tuned Matched Filtering (MTMF)

method has been used for mineral occurrence mapping.

16. GIS technique has been used to generate Digital Gravity Model (DGM) from

bouguer gravity anomaly data using surface interpolation method.

17. Gravity highs and lows have been identified from DGM.

18. An aspect map has been prepared from the DGM, which has been used to

demarcate gravity lineaments. The aspect map has also been overlaid on

lithological map (Saha, 1994) to find the interrelationship.


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19. Gravity lineaments have been superimposed over DGM and lithological map

(Saha, 1994) to study their interrelationship.

20. The lithological map (Saha, 1994) of the area has been draped over the DGM to

correlate gravity and geology of the area.

1.11 Plan of the Thesis

The present work is presented in seven chapters in this Thesis as described below.

Chapter 1: This is an introductory chapter of this Thesis. Location and Geological setup

of the study area and Review of literature are discussed. These are followed by Scope of

the work; Objectives, Data used and Methodology.

Chapter 2: This chapter describes the procedures for identification of lineaments and

structural features and results over part of the study area using: i) visual interpretation of

ERS-1 SAR image, and ii) Fast Fourier Transformation enhanced ERS-2 SAR image.

Chapter 3: Techniques for fusion of optical and synthetic aperture radar (SAR) imagery

for mapping of various lithological units over a part of the study area are discussed in this

chapter. The inferred lithological map has been validated with the lithological map of

GSI (1998) by change detection analysis.

Chapter 4: This chapter describes an approach for regional lithological mapping based

on estimated land surface temperature and relative emissivity extracted from MODIS TIR

imagery. The inferred regional lithological map has been validated with lithological map

of Saha (1994) by change detection analysis.

Chapter 5: The efficiency of Advanced Spectral Analysis techniques as a possible means

for identification of different mineral occurrences using Landsat ETM+ imagery over part

of the study area has been discussed in this chapter.


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Chapter 6: This chapter discusses procedures for generation of Digital Gravity Model

(DGM) from Bouger gravity anomaly map and aspect map from DGM. Gravity highs and

lows are delinated from DGM. Aspect map has been utilized for delineation of gravity

lineaments and lithological boundaries. 3D gravity model has been generated for better

undersatnding of gravity distribution corresponding to different lithounits.

Chapter7: The results obtained in various chapters are summarized and conclusions

drawn from this study are presented in this chapter.

1.12 Contribution of Scholar • Multi sensor satellites (IRS-1C LISS III, Landsat ETM+, MODIS and ERS-1

SAR and ERS-2 SAR) covering the broad range of electromagnetic radiation

spectrum (optical, infrared, thermal infrared, and microwave) have been

successfully utilized in studying a geologically complex and mineralogically

important region of India.

• Various state-of-art image processing and GIS techniques have been successfully

utilized.

• Three papers in International journals (Pal et al., 2006a, 2007a and 2007b) and

one paper in Indian journal (Pal, at al., 2006b) have been published. Further, and

two revised manuscripts (Pal et al., 2007d and Majumdar et al., 2007) one

manuscript (Pal, et al., 2007e) have been communicated to International journals.

• Two papers (Pal, et al., 2005 and 2007c) have been presented at Conferences.

singhbhum

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