STRUCTURAL ANALYSIS IN THE CENTRAL SECTOR OF THE …

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Int. J. of Geol. & Earth Sci., 2017 Dr. Chandrabali Mukhopadhyay, 2017

STRUCTURAL ANALYSIS IN THE CENTRALSECTOR OF THE NORTH SINGHBHUM FOLD BELTIN AND AROUND SINI, JHARKHAND DISTRICT,

BIHAR, INDIA

The study area is dominantly made up of pelitic, semipelitic schists, amphibolites and quartzite.The metasedimentary sequence has been intruded by granitic rocks in two phases. Signaturesof polyphase deformation are clearly discernible in these rocks. The first phase of deformation(D1) produced schistosity (S1) with downdip lineation. Mesoscopic isoclinical folds are rarelyseen. The second phase deformation (D2) produced asymmetric folds on S1 and axial planarcrenulations cleavage (S2). In the northern part S2 has almost completely obliterated the earlierschistosity and the regional schistosity is here combined (S1/S2). The last deformation episodeD3 gently folded S1 and S2 on transverse axial planes. Mylonites, ultramylonites and phyllonitesare confined to the southern part of the area which represents the western extension of theSinghbhum Shear Zone. Mylonitic foliation within the feldspathic schist and micaceous phylloniteis parallel to S1. Isolated late stage shear zones occur throughout the area. Evidences suggestthat shearing started during D1 and occurred during different stages in the deformation history.The deformation events comprising D1, D2, D2A and ductile shearing are parts of the samedeformation cycle with N-S compression combined with simple shear with top-to-the-southsense of movement. Late stage longitudinal compression occurs during D3.

Keywords: Pressure solution bands, Transposed schistosity, Differentiated crenulationcleavage, Extensional crenulation cleavage, Progressive shearing, Conjugate shearplanes

INTRODUCTIONThe E-W trending Proterozoic fold belt of NorthSinghbhum, is flanked to the south by the Archeannucleus of Singhbhum and to the north by theChhotanagpur Granite Gneiss terrain. A medianbelt of mafic volcanics (Dalma lavas) subdivides

1 Ph.D. Designation, Part-time Lecturer, W.B.C.T.S., ADDL.CCT, PG Circle 7122-1575.

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Int. J. of Geol. & Earth Sci., 2017

Research Paper

the fold belt into two parts. The present area liesin the central part of the southern section of thefold belt. The Singhbhum Shear Zone which is amore than 100 Km long arcuate belt withnorthward convexiety passes along the southernflank of the North Singhbhum Fold Belt. This

Dr. Chandrabali Mukhopadhyay1*

*Corresponding Author: Dr. Chandrabali Mukhopadhyay [email protected]

Received on: 12th June, 2017 Accepted on: 12th August, 2017

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Singhbhum Shear Zone (or Copper Belt Thrust)seperates Iron Ore “Stage” and SinghbhumGranite in the south from Chaibasa “Stage” in thenorth (Dunn and Dey, 1942) (Figure 1). In therecent years it has been proposed that the IndianPeninsular Shield is made up of two blocks, thesouthern Dharwar-Bastar block and the northernBundelkhand block. The blocks wereamalgamated during mid-Proterozoic and theirjunction is referred to as the Central IndianTectonic Zone (CITZ, Radhakrishnan, 1988;Yedekar et al.,1990; Jain et al., 1995 and Acharya,2001). The north Singhbhum fold belt is theeastern continuation of CITZ.

METHODS OF STUDYMapping was done on 1:25,000 scale using anenlarged copy of the Survey of India Toposheet

as base map. Altitudes of various planar andlinear structures were measured and the relationsbetween different structural elements werestudied both in hand specimen and thin section.Structural and lithological maps were prepared.

LithologyThe area (latitudes 22046’N and 22051’N andlongitudes 85054’E and 8603’E ) (Figure 2) coversa part of the Singhbhum Shear Zone and an areanorth of it within the Proterozoic fold belt of NorthSinghbhum and is located near the small townshipof Sini and Gamaria, Singhbhum District,Jharkhand. The principal rock types encounteredin Sini area are quartzite, mica schist and phyllite.Amphibolites (both massive and schistosevarieties) are present as discontinuous lenses.Massive granite and granophyres are found in the

Figure 1: Geological Map of Proterozoic Fold Belt of North Singhbhum

Source: Modified from Dunn and Dey (1942)

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southern part of Sini area. Very fine grainedfeldspathic schist is also present along the banksof Sona Nadi, it is a granitic ultramylonite. Doleriteoccur as lenses.

STRUCTURAL ELEMENTSPlanar StructuresBedding (So)Bedding is found in quartzite and they are markedby colour and compositional banding. Thethickness of these bands varies from a few mmto a few cm. Bedding is usually not recognizablein the mica schists. In some semipelitic schistsand tourmalinite compositional layers definebedding. In most instances bedding is parallel tothe regional schistosity due to isoclinal nature ofthe first folds and they cross cut each other onlynear the hinges of the mesoscopic first folds onbedding.

Schistosity (S1)It is the dominant planar element in most of therock types in the southern and central parts ofthe area. Megascopically, schistosity is defined

by parallel arrangement of muscovite, biotite andsometimes chlorite. In thin sections the flakyminerals form thin laminae, which at places showan anastomosing pattern enclosing long, lenticularquartzose domains (Hobbs et al., 1976; andBorradaile et al., 1982).

An interesting structure is found in the bandedsemipelitic rocks near Charakpathar. Herequartzose and micaceous layers in bandedsemipelite is cut across by an oblique set ofcompositional bands defined by regularly spacedthin micaceous laminae separating quartzosedomains. It is inferred that this secondary bandingoriginated at relatively low grade of metamorphismby a process of solution transfer associated withthe formation of differentiated crenulation cleavage(Gray, 1977a and 1979) parallel to the axial planesof folds on a primary fabric parallel to bedding.Subsequent recrystalization during higher grademetamorphism obliterated the traces of earliercrenulated fabric and we now observe a regularsecondary banding cutting across the primarycompositional bands (bedding). Such pressuresolution bands accompanying the formation ofcrenulated cleavage has been described byRamsay and Huber (1987, p. 439) as tectonicallyformed striping or banding. This secondarybanding, a first generation structure (S1) is parallelto the schistosity of the adjacent mica-schist.

Mylonitic Foliation (S1)In the southern part of the area, the extremelyfine grained feldspathic schist represents anultramylonite derived from a granitic protolith. Themain foliation is defined by parallelism of tiny flakesof mica and chlorite as well as very thinmicaceous or chloritic laminae within anultramylonitic matrix. Within feldspathic schistsexposed along Sona Nadi and Sanjay Nadi (inthe southern part of the study area) a regular

Figure 2: Location Map of Study Area

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colour banding is found (Figures 3). Lighter bandsare ultramylonitic and composed of fine-grainedquartz and feldspar, whereas darker bands aremade up of muscovite, biotite and chlorite flakes.A banded migmatite could have been the protolithof this banded mylonite. Alternatively, thedistributed mafic and felsic minerals in the originalgranite could have become concentrated in bandsduring deformation as a result of contrasted,ductility (Passchier et al, 1990, p. 26-34, Ramsayand Huber, 1987, p 591). In the less deformedgranitic rocks an augen structure is developedand lenticular quartzo-feldspathic augen arewrapped around by anastomosing micaceouslaminae. With greater intensity of deformation the

rock is converted to a finely foliated quartzo-feldspathic rock with only a few tinyporphyroclasts. The mylonitic foliation in both thefeldspathic schist (ultramylonite) and the lessdeformed granite has a very strong nearlydowndip stretching lineation. The mylonites showisoclinals/tight early folds of reclined nature aswell later asymmetric folds with gentle to steepplunges. The foliation in phyllonites is alsogrouped under mylonitic foliation. Characteristicallythe phyllonitic foliation is of composite naturewith sigmoidal S and C planes (S-C fabric)(Figure 4). Typically the angle between the twoplanes is 20o-30o. The movement planes aredefined by micaceous/chloritic laminae and theS-planes by small phyllosilicate flakes. Often theC-surfaces ramps up to a higher level givingrise to sigmoidal shape. Such ramps aresubparallel to the S-fabric defined by smallphyllosilicate flakes. Asymmetric tails againstporphyroblasts or lenticular aggregates arecommon. The phyllonitic foliation is cut acrossby later shear planes (C’-planes, Berthe et al.,1979). The foliation in the mylonites andphyllonites is parallel to the schistosity in the

Figure 3: Ultramylonite with AlternateQuartzo-Feldspathic and Chlorite-Biotite

Bands Near Sona Nadi, SouthernPart of the Area

Figure 4: S-C Fabric in Phyllonite,Occassional Dragging of the Oblique FlakesAlong the Movement Surfaces South of Sini

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neighbouring rocks; hence these are allgrouped together as S1.

Crenulation Cleavage/Transposed Schistosity(S2)In the southern part of the area the schistosity isfolded and crenulation cleavage parallel to theaxial planes of the folds is well developed in micaschists. Both discrete and zonal crenulationcleavages (Gray, 1977b) are observed. In somebanded rocks the cleavage appears as discreteplanes in the quartzose bands (Figure 5) while inthe micaceous bands it is of zonal nature. Somemica flakes have recrystallised parallel to thecrenulation cleavage. In the northern part of thearea near Sini Pahar, Charakpathar and Khadan

Hills the main foliation in the meta-pelitic rocksapparently appears to be a schistosity, and itsformation is accompanied by metamorphicdifferentiation that has given rise to a few mmthick siliceous bands separated by thinmicaceous laminae. These correspond to M-domains or cleavage domains and QF-domainsor microlithons (Davies, 1996). However, carefulexamination reveals that the fabric is adifferentiated crenululation cleavage, and foldedearly schistosity is clearly recognizable within thequartzose domains. S1 can sometimes be tracedcontinuosly across the domain boundary. Inmicaceous bands the S1 mica flakes are foldedand an axial planar S2 fabric has developed. Atmany places S2 has almost completelytransposed the earlier schistosity (S1), butisolated first fold hinges (Figure 6) defined byearlier mica flakes are still present, their axialplanes being parallel to the main foliation (S2)

In some thin sections within M-domains relictearlier mica is present as isolated transverseflakes truncated by S2-parallel flakes. Similarfeatures are also seen at Kukudungri. It is,therefore, concluded that the main planar fabric

Figure 5: Discrete Crenulation Cleavagein Quartzose Band in Banded Toumalinite,

Kukudungri, Northern Part of the Area

Figure 6: S2 Tranposing S1, Isolated RelictHinge of D2 Fold Defined by S1 Mica,

Sini Pahar

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in the northern part of the area is a secondgeneration structure (S2) which has almostcompletely transposed the earlier schitosity (S1).Stages in the development of micaceous andquartzose domains in such transposed foliationare schematically illustrated in (Figure 7).

Linear StructuresMineral lineation is best developed in pelitic schist,amphibolites and feldspathic schist. In theschistose rocks this is formed due to lineararrangement of biotite, muscovite and chlorite onthe schistosity surface. In some feldspathicschists elongated clots of biotite and chlorite onthe mylonitic foliation define mineral lineation. Insome deformed granites ribbon shaped quartzgrains define a lineation on the foliation surface.Mineral lineation in the rocks of southern part ofthe area is nearly downdip. These lineations onschitosity are first generation lineation (L1).Striping lineation is the trace of bedding on theschistosity plane and appears as bands ofdifferent colours on the schistosity plane. It isfound within quartzite and pelitic schist, mostly inthe southern part of the area. In the pelitic schistof the northern part of the area the intersection ofcrenulation cleavage (S2) and schistosity (S1)defines a second-generation lineation (L2) and is

parallel to axes of puckers on schistosity. Inamphibolits elongation of amphibole needlesdefines the mineral lineation which is parallel tothe second-generation crenulation axes and S1/S2 intersection lineation.

Minor Folds And PuckersMinor folds of this area belong to differentgenerations. The earliest folds (D1) are smallisoclinals folds with axial plane schistosity foundin feldspathic schist, banded semiplite andtourmalinite. Their axes are parallel to the downdipmineral lineation and striping (L1). Secondgeneration folds (D2) are crenulations onschistosity and mylonitic foliation. They have aconstant sense of asymmetry, being S-shapedin section looking from east or Z-shaped lookingfrom west (Figure 8). Their plunge is generallylow but variations are observed. These minorfolds bend the early lineation.

At places in Sini Pahar and Charakpathar i.e.in the northern part of the area, the folds on S1

are overturned and have northerly dipping axialplanes. Folds and crenulations with transverseaxial planes (D3) have developed on the differentplanar fabrics. The strike of axial planes of thesetransverse minor folds is nearly perpendicular tothat of the regional schistosity. Their axes are

Figure 7: Stages in the Development of Quatzose and Micaceous Domains in CrenulationsCleavage

Source: Hobbs et al. (1976)

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nearly downdip on the schistosity surface. Inaddition to these, very late folds with gently dippingaxial planes have bent the S2 fabric.

Shear Zone StructuresThe feldspathic schists are ultramylonites derivedfrom granite. The occurrence of these and of thephyllonites in the southern part of the present areamarks the Singbhum Shear Zone. The nearlydowndip lineation indicates the movementdirection during the main mylonitization phase.There is no distinct structural or metamorphicbreak across the shear zone. The structuralfeatures of the Singhbhum Shear Zone are well

documented in the region east of the present area(Ghosh and Sengupta, 1990; and Mukhopadhyayand Deb, 1995). The mylonitic foliation is parallelto the schistosity in the surrounding schists andphyllites (Figure 9). Hence, the mylonitisation isregarded to have started during the firstdeformation. Shear sense is indicated byconsistent asymmetry of minor folds of themylonitic foliation, c-c’ relation, asymmetricdeflection of foliation against porphyroblasts, stair-stepping of tails (Passchier and Trouw, 1998)against lenticular aggregates of porphyroblastsand elongation of dynamically recrystallizedquartz (Figure 10). Axes of the asymmetrical foldsmylonites and phyllonites have variable plunge,from being nearly downdip to gentle westerlyplunge. The folds also show varying degrees oftightness. While in cross section the folds alwaysshow the same sense of vergence (S-shapedviewed from east), on the horizontal surface bothS and Z shapes are found depending on thedirection of the plunge. Similar phenomena havebeen described by Mukhopadhyay and Deb(1995) east of the present area. Following them,we interpret this as being due to rotation in

Figure 8: Asymmetrical D2 Folds in Section,Sona Nadi, S-Shaped Looking from East

and Z-Shaped Looking from West

Figure 9: Mylonitic Foliation in FeldspathicSchist Folded on Transverse Axial Planes,

Sona Nadi, Southern Part of the Area

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opposite sense of axes of asymmetric minor foldsduring progressive shearing (Figure 11).

Though the effects of shearing are morecommon in the southern part of the area, even inthe higher grade rocks of the north shear planesare discernible.

The presence of ultramylonitic granitesindicates a phase of pre-mylonitisation graniteemplacement. On the other hand, the youngercoarse-grained granite and granophyres are post-mylonitization. However, later discrete shearzones, tens of centimetres wide, are present inthem and the granite is converted to quartzo-feldspathic schist within these discrete shearzones. The shear zones sometimes showanastomosing pattern and at places conjugateshear zones (Figure 12) are present.The internalmylonitic foliation in these shear zones is at acuteangle to the shear zone walls and often displaysa sigmoidal curvature. The sense of movementcan be inferred from the sigmoidal shape of thefoliation. In the central part of the shear zonewhere the deformation is more intense thefoliation is almost parallel to the shear zone walls.Majority of those discrete shear zones in graniteshow dextral sense of movement on horizontalsurface. The presence of the shear zones withingranite indicates that shearing movementcontinued to the late stages in the history ofevolution of the belt.

Deformation SequenceThe first phase of deformation (D1) produced the

Figure 10: Asymmetrical Deflectionon Foliation Against Garnet Porphyroblast

Figure 11: S Shape and Z Shape in Plan of D2Minor Folds Caused by Rotation in Opposite

Sense of Axis of Asymmetrical Folds

Source: Mukhopadhyay and Deb (1995)

Figure 12: Conjugate Shear Zones in Granite,Sona Nadi (S-C Angles are Only Schematically

Shown), Southern Part of the Area

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schistosity (S1) which is axial planar to the minorisoclinal folds. Early folds are found in feldspathicschist near Ukri in the southern part of the areaand in banded tourmalinite and pelitic schist nearKukudungri in the eastern part. In the semi-peliticschist a secondary compositional banding is atplaces produced by the deformation. Thestretching lineation (L1) associated with thisdeformation is nearly downdip on the schistositysurface.

The second phase of deformation (D2)produced asymmetric folds and bent the firstlineation. Axial plane crenulation cleavage (S2) isobserved in the southern part of the area and inthe northern Part S2 has completely transposedS1 to become the main planar fabric in the rocks.Both S1 and S2 are northerly dipping but S2 dipsmore steeply than S1.In the northern part of thearea near Bikanipur and Rangamatiya, the mainfoliation, which is a transposition structure (S2),is again folded at a few places on steep northerlydipping axial planes. Unlike in S2 no segregationbanding is produced parallel to these axial planes.These folds have the same sense of asymmetryas the D2 folds and probably representcontinuation of the D2deformation episode. Theseare labelled as D2A folds. Mylonitization involvedslip on the D1schistosity surface and the myloniticfoliation is parallel to S1. However shearingcontinued in the late stages also though itsintensity was less. This is indicated by thepresence of isolated shear zones within theyounger granophyre and of S2–parallel shearplanes in the staurolite-kyanite-sillimanite bearingmica schists (Figures 13).

Hence it is concluded that mylotinizationstarted during D1. The shear sense criteriaindicate top-to-the-south sense of movement(thrust sense). The asymmetry of D2 folds is

consistent with this sense of movement and it islikely that D2 folds is consistent with this sense ofmovement and it is likely that D1, and D2/D2A

represent early and late stages of a continuousepisode of deformation in which south directedshear was an important component. Extensionalcrenulations cleavage with gentle northerly diphas caused sigmoidal curvature of S1 and S2

foliation. These are c’ planes formed at late stageof shearing deformation.

A third phase of deformation (D3) has givenrise to broad warps on the schistosity withtransverse axial planes and nearly downdip axes.An excellent example of Type 2 interferencepattern (boomerang form) resulting from D2 andD3 folds is observed at Kukudungri (Figure 14).The early mineral lineation is bent by tightasymmetric D2 folds with steep dipping axialplanes. The D2 axial planes are refolded sinistrallyby D3 folds. The D2 fold axes are also bent by thelater deformation producing Type 2 interferencepattern. The D2A folds have NNE-SSW trendingsubvertical axial planes and the axes have

Figure 13: S2 Parallel Shear Surfaces Markedby Granules of Staurolite and Small ParallelFlakes of Biotite Truncating Earlier Biotite

Porphyroblasts, Direction Sense of Movementis Indicated by Dragging of Basal Cleavage

of One Biotite Porphyroblast, Near Sini Pahar,Northern Part of the Area

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different orientation on the two limbs of the D2

folds. In addition, gentle folds on S2 with sub-horizontal to low dipping axial planes aresporadically found. These have resulted fromvertical compression on the steep dipping foliationand probably formed at a very late stage due tosuperecumbent load.

Structural SynthesisRegional schistosity is northerly dippingthroughout the study area. Isoclinal minor foldson compositional banding, with axial planarschistosity, are observed at places.

In the south within the granite mylonite and thephyllonitic rock the mylonitic foliation is parallel tothe first schistosity. This would suggest that themylonitization started during the first phase ofdeformation (D1). The nearly downdip minerallineation represents the stretching direction andindicates the direction of movement duringshearing. Shear sense indicators point to thrusttype movement (top-to-the-south). The higheasterly rake of the lineation maximum (i.e., inthe southern part of the area ) indicates that thethrust movement was combined with horizontalsinistral component. This mylonitic zone is the

western continuation of the Singhbhum ShearZone.

The schistosity and mylonitic foliation arefolded into asymmetrical folds (D2) with axialplanes dipping more steeply than the schistosity.The folds had gentle plunges in the initial stagesand with increasing deformation the axes rotatedtowards the direction of elongation. They have aconstant sense of vergence (S-shaped in sectionlooking from east), consistent with the top-to-thesouth shear sense.

In the northern part of the study area near SiniPahar and Charakpathar the main foliation ismore steeply dipping compared to the southernpart of the area. This is because this is the laterfoliation (S2) which has almost completelytransposed the earlier schistosity (S1). Continueddeformation (D2A) has at a few places folded theS2 fabric on steep northerly dipping axial planes.

Consistency of the asymmetry of the D2/D2A

folds with the other shear sense criteriaassociated with mylonitization suggest that D1,D2 and D2A represent the early and late stages ofa continuous period of deformation. Thisdeformation was caused by N-S compressioncombined with simple shear that gave rise toductile shear zone with thrust sense of movement(top-to-the-south) combined with a sinistralhorizontal component.

Mylonitic fabric and downdip lineation areabsent in the northern part of the area where therocks are more metamorphosed in comparisonto the southern part. This metamorphism waspost-mylonitization and it has obliterated anyshear related fabric that might have been presentin the northern part. It is also to be noted that inthe northern part the D2 folds are mostly gentlyplunging and hence their axes have not rotatedmuch from their initial orientation.

Figure 14: Interference Pattern Producedby D1 and D2A Folds, Mineral Lineation is Bent

by D2 Folds

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A third set of minor folds has steep dippingaxial planes, which are transverse to the strike ofthe main planar fabric and the axes are nearlydowndip on main foliation plane. These belong tothe last stage of deformation and are presentthroughout the study area.

CONCLUSIONConclusion from the deformation history initialasthenospheric upwelling and rifting followed byintracontinental subduction and compressionaldeformation leading to loading and heating isenvisaged. Sedimentation was going on along thecontinental margin of the southern SinghbhumArchaen nucleus when the subduction processstarted. The metasedimentary sequence hasbeen intruded by granitic rocks in two phases.Weakly deformed younger granite (‘ArkasaniGranophyre’ of Dunn, 1929) intruded during the

waning stage of deformation. Signatures ofpolyphase deformation are clearly recognisablein the rocks. First phase deformation (D1)produced schistosity (S1) with downdip lineationand the rarely observed isoclinals minor folds.Second phase deformation (D2) producedasymmetric folds on S1 and axial planarcrenulations cleavage (S2). In the northern partS2 has completely obliterated S1 and the regionalschistosity is here combined S1/S2. The down dipmineral lineation is absent in northern schistoserocks having transposed S1/S2 schistosity. Acontinuation of the second phase of deformation(D2A) folded the transposed schistosity (S1/S2) onsteep northerly dipping axial planes. The lastdeformation episode D3 gently folded S1 and S2

on transverse axial planes. Mylonitic foliation isparallel to S1. Mylonites and ultramylonites areconfined to the southern part of the area, whichrepresents the western extension of theSinghbhum Shear Zone. Sporadic small scaleshear zones are found even in the schistose rocksto the north and within the late phase granite.Mylonitisation started during D1, but formation oflate stage shear zones and the asymmetry of D2

and D2A minor folds indicate existence of simpleshear regime throughout the deformation history.Shearing had consistent thrust sense (top-to-the-south) movement. D1, D2, D2A and ductileshearing parts of the same deformation cycle withN-S compression combined with simple shearwith top-to-the-south sense of shear.

Deformation history of the present area isconsistent with the tectonic model presented byGhosh et al. (2006) (Figure 15). Their modelenvisages initial asthenospheric upwelling andrifting followed by compressional deformationleading to loading and heating. New informationfrom sediment geochemistry suggests active

Figure 15: Tectonic Model of North SinghbhumFold Belt

Source: Ghosh et al. (2006)

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continental margin setting. Hence a subductionzone (intracontinental subduction) processstarted when sedimentation was going on alongthe continental margin of the southern SinghbhumArchean Nucleus. More information about thesedimentation history, geochronology and timingof deformation and metamorphic events isneeded to tightly constrain the tectonic model.

ACKNOWLEDGMENTI am indebted to Prof. Dr. Dhruba Mukhopadhyay,my teacher and supervisor for his guidandance,invaluable suggestions. My sincere thanks goesto Dr. T Bhattacharya of Department of Geology,University of Calcutta for extending his support inmany ways. This research project leading to Ph.Dis funded by UGC.

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5. Ramsay John G and Huber Martin I (1987),“The Techniques of Modern StructuralGeology”, Vol. 2.

6. Spry Alan-Metamorphic Textures (1976),p. 350, Pergamon Press Ltd.

7. Winkler G F (1988), “Petrogenesis ofMetamorphic Rocks”, Narosa PublishingHouse, New Delhi.

8. Winter John D (2001), “An Introduction toIgneous and Metamorphic Petrology”, p. 297,Prentice Hall.

9. Yardley (1989), “An Introduction toMetamorphic Petrology”, Narosa PublishingHouse, New Delhi.

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STRUCTURAL ANALYSIS IN THE CENTRAL SECTOR OF THE …