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GSI-CHQ-802
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GEOLOGICAL SURVEY OF INDIA
PROGRESS REPORT FOR THE FIELD SEASON 1959-‘60
(OCTOBER 1959 TO MARCH 1960)
PROGRESS REPORT ON THE SYSTEMATIC MAPPING OF BUNDELKHAND
GRANITES IN PARTS OF JHANSI DISTRICT AND INTERVENING PARTS OF
TIKAMGARH DISTRICT, UTTAR PRADESH AND MADHYA PRADESH
By
H.N. Singh,
Geologist
Geological Survey of India
October, 1961.
Field season programme for 1959-‘60,
Geological Survey of India,
U.P.-Punjab Circle, item No. 1, U.P. Page No. 54.
GSI-CHQ-802
PROGRESS REPORT ON THE SYSTEMATIC MAPPING OF BUNDELKHAND
GRANITES IN PARTS OF JHANSI DISTRICT AND INTERVENING PARTS OF
TIKAMGARH DISTRICT, UTTAR PRADESH AND MADHYA PRADESH
By
H.N Singh,
Geologist,
Geological Survey of India.
CONTENTS
Page No.
I.
INTRODUCTION
1
II.
ACKNOWLEDGEMENT
1
III.
LOCATION AND ACCESSIBILITY
1
IV.
PHYSICAL FEATURES
2
V.
PREVIOUS WORK
2
VI.
GEOLOGICAL SETTING
2
VII. DESCRIPTION OF GRANITES
3
General
3
Coarse-grained pink granite
4
Coarse grained grey granite
4
Medium grained pink granite
5
Medium grained grey granite
5
Fine grained pink granite
6
Fine grained grey granite
6
Petrography
6
VIII. INCLUSIONS
7
General
7
Amphibolite and allied rocks
8
Quartzite and allied rocks
9
Granulite (?) and allied rock
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Hornblende granite
11
Hornblende biotite schist
11
IX.
QUARTZ REEFS
11
X.
PEGMATITES
12
XI.
DOLERITE DYKES
12
XII. STRUCTURAL GEOLOGY
13
Strike trend of inclusions
13
Foliation
13
Joint
13
XIII. GENERAL REMARKS
14
XIV. ECONOMIC GEOLOGY
15
Sulphide mineral
15
Pyrophillite
15
Road Metals and Railway Ballasts
16
XV. WATER SUPPLY
16
XXVI LOCALITY INDEX
16
XXVII. BIBLIOGRAPHY
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PROGRESS REPORT ON THE SYSTEMATIC MAPPING OF BUNDELKHAND
GRANITES IN PARTS OF JHANSI DISTRICT AND INTERVENING PARTS OF
TIKAMGARH DISTRICT, UTTAR PRADESH AND MADHYA PRADESH
By
H.N Singh,
Geologist,
Geological Survey of India.
ABSTRACT
In continuation of the programme of systematic mapping of Bundelkhand granites and
gneisses, carried out by the Geological Survey of India. Since 1953, an area of 311 sq.kms. lying in
Survey of India toposheet No 54 K/15 was mapped. Major part of the area is occupied by
Bundelkhand granites which show wide variation in colour (from pink to grey), texture (coarse to fine
grained, at places porphyritic) and mineralogical composition The coarse grained pink granites and
the medium grained grey granites both bearing some ferromagnesian minerals, form the two dominant
types of granites of the area. The third in order of abundance is the fine grained pink granite, poor in
ferro-magnesian minerals, which occur mostly in the form of very long bands and irregular patches
associated with the other two varieties of granite.
The granites in general are either massive or weakly foliated. The foliation strikes commonly
between N 75º/45ºW-S75º-45ºE direction. Numerous dark grey and pinkish-coloured bands of
schistose crushed granite, trending in varying directions were also encountered. These mylonitic
bands are seen mostly in the coarse grained pink varieties.
The granites bear a large number of inclusion of hornblende rocks, quartzites, granulites (?)
and schists. Many of the inclusions show evidences of reaction with the granites.
The late phase of igneous activity is manifested in the intrustion of very large bodies of quartz
reef and dolerite dykes.
The quartz reefs usually trend in the NE-SW direction while the dolerite dykes have a NW-SE
trend. The trend of the quartz reefs appears to cut the regional trend of the inclusions. Though the
evidences met with in the area are not conclusive, it would appear that the dolerites are younger than
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the quartz reefs.
It is too premature to give any view regarding the origin and the emplacement of the granite
bodies. Certain facts gathered during the field and the preliminary laboratory studios, having some
bearing on the above problem, have been recorded and discussed in the report.
GSI-CHQ-802
PROGRESS REPORT ON THE SYSTEMATIC MAPPING OF BUNDELKHAND
GRANITES IN PARTS OF JHANSI DISTRICT AND INTERVENING PARTS OF
TIKAMGARH DISTRICT, UTTAR PRADESH AND MADHYA PRADESH
By
H.N Singh,
Geologist,
Geological Survey of India.
INTRODUCTION.
In continuation of the programme of systematic and detailed mapping of the Bundelkhand
granites, carried out by the Geological Survey of India, since 1953, a party consisting of Sarvashri
Kedar Narain, Geologist (Sr.), A.S. Dass, Assistant Geologist and the author was deputed to carry out
mapping in parts of Jhansi district. U.P. and intervening portions of Tikamgarh district M.P. Mapping
was taken up during the last week of October, 1959, when, the author joined Shri Dass in the field and
working with him, covered an area of about 21 sq. kms., in the sheet No. 54 K/15. Later on Shri
Kedar Narain joined the party, and an area of 44 sq. kms. was covered collectively in the area around
Kachneo and Arjar falling in toposheet No. 54 K/15. The party then splitted and each of the members
took up separate areas of systematic mapping. The author continued working in the same sheet
(54K/15).
ACKNOWLEDGEMENT
Shri S.C Chakravarty, Superintending Geologist-in-Charge, U.P,,Punjab Circle, Northern
Regional Office, Geological Survey of India, paid a visit to my camp at Sakrar. He went over part of
the area mapped by me. He gave guidance and suggestions regarding the field work and the problems
involved.
LOCATION AND ACCESSIBILITY
The mapped area lies in the southern part of the sheet No. 54 K/15, between the parallels of
latitudes 25°15’ and 25°25’ N and longitudes 78°45c and 79°00cE. The Jhansi-Manikpur section of the
Central Railway passes through the area in an east-west direction. About four to six kms, north of this
railway line runs the Jhansi-Nowgong all weather road. The western part of the area is traversed by
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another all weather road which coming from Tikamgarh joins the Jhansi-Nowgong road near Nivari.
The interior parts of the area out approached by numerous cart tracks, many of which are jeepable
during the fair weather
PHYSICAL FEATURES
The country is generally plain or rolling, with interspersed hills and ridges, not exceeding 183
metres in elevation from the ground level. The quartz reefs form long chains of high ridges and are the
very conspicuous features of the terrain. The hills made up of granites are generally flat topped. A
series of such hillocks exists between Tejpura and east of Kagar.
There are numerous streams in the area flowing in the northerly direction, the largest amongst
them being the Barawa Sagar nala which flows in the southeastern part of the area.
PREVIOUS WORK
Medlicott, Hacket. Mallet and Wilson mostly worked in the Bundelkhand granites and
gneisses area during the later part of the nineteenth century. The problem relating to these rocks
received renewed attention from several geologists during the last decade. During the field season
1953-‘54 the Geological Survey of India again took up the systematic mapping of Bundelkhand
granites and gneisses. Accounts of the work done so far, are furnished in the progress reports for the
various field seasons submitted by Dr. A.G Jhingran, Deputy Director, Geological Survey of India
and other officers of the G.S.I. In his presidential address in the Geology section of the 45th session of
Indian Science Congress, held at Madras-(1958), Dr. Jhingran gave an upto date account of these
granites and problems relating to their origin and other allied topics.
GEOLOGICAL SETTING
There exists still today some uncertainties regarding the age of Bundelkhand granites. They
have been grouped in the Archean formation and are considered equivalent to the Banded Gneissic
complex of Rajasthan There is also no uniformity of opinion regarding the age of Banded Gneissic
complex. According to some, it represents the granitised Aravallis, while Heron (Geology of India
and Burma, M.S. Krishnan, pp. 129-131) takes it to be older than Aravallis resting unconformably on
the granites. Further, the various varieties of Bundelkhand granites comprising the massif may not be
of a single generation and there might have been more than one period of “intrusion”. Until the entire
massif is mapped in detail it will not be possible to establish the precise sequence of various varieties
of the Bundelkhand granites. In tentative succession given below the different varieties of granite
have been grouped in one division, which is subject to alteration in the light of further wok and
petrological examinations
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4. Dolerites
3. Quartz reefs and pegmatities (?)
2. Bundelkhand granites of different varieties
1. Amphibolites, quartzites, granulites (?) and various hybrid rocks.
DESCRIPTION OF GRANITES
General
The granites are very heterogeneous in character, in colour, texture and in the abundance of
mafic minerals contents. On the one hand these are coarse grained with the grain size varying upto 1
cm. across and on the other it is extremely fine grained and dense.
In colour the rock vary from pink through greyish pink to grey. The proportion of mafic
minerals varies from place to place. The mafic minerals in the rocks are mainly biotite, hornblende
and chlorite. In some cases they are mainly biotite, whereas in others hornblende is predominant
Based on the above features Dr. Jhingran and other workers of the Geological Survey of
India, classified the granites into 11 varieties ( Jhingran (1954), Puri and Mathur (1957). ). Though
attempts were made to map as many varieties of granites in the field, it is to be noted that there Could
be no water tight compartments between the different varieties of granite which merge imperceptibly
from one to the other. At times it is extremely difficult to fit in a particular rock type even to the rather
elaborate classification mentioned above. Further, at some places more than one variety occur in
juxtaposition with each other and it is difficult to delineate them in the scale of the map used. In such
cases only the dominant varieties have been shown.
Broadly speaking, of all the varieties of the granites met with in the area, the most dominant
types are the (i) coarse grained pink granite bearing ferromagnesian minerals and (ii) medium grained
grey granite also bearing some ferromagnesian minerals- the former being more dominant than the
latter. The coarse grained pink variety is developed in the south-eastern part of the sheet No. 54K/15,
whereas the medium grained granite occurs mostly in the north-western part. It is important to note
that the Rajapur quartz reef marks the boundary between the two varieties for a distance of 11 kms.
upto Nivari, where the boundary swerves in the easterly direction.
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Coarse-grained pink granite (1a).
The granite in general is pink coloured, coarse grained and bear a little amount of ferromagnesian minerals. At some places e.g.,3.2 kms, west of Teharka, it is found to become very rich in
ferro-magnesian minerals. Here it is associated with a few bands of amphibolite bearing rocks.
The granite either massive or crudely foliated. Very often, bands of dark grey and pink
coloured mylonitic rock trending in varying directions are encountered. These bands vary in width
from 2.5 cms. to about 23 cms. and run sometimes for 6 to 19 metres. The granites near the contact
with the mylonitic bands are locally strongly foliated; foliation in general making a very small angle
with the trend of the mylonitic bands, though near the contact the foliation, at some places, parallels
the trend of the mylonite bands.
In the southern part of the area between Kagar and Yobri Khirk the granites show porphyritic
character with the development of big phenocrysts of felspar ranging upto more than 5 cms. across.
The phenocrysts have random orientation and are formed both of grey and pink felspars. The
porphyritic granite is patchy in distribution and appears to be a local variant of the coarse grained pink
granite.
The granite at some places also shows well developed foliation near the contacts with
inclusions. The foliation is sometimes so intense that the rock develops schistose character. Such
foliated granites are seen (i) south of Nanora (ii) 0.4 kms, south of Churari, (iii) 0.6 kms. south-west
of Jakhangaon. Usually the foliated granite does not extend over 12 metres in length.
The inclusions commonly seen are of (i) quartzites and (ii) amphibolite and rocks possibly
derived from it. The granite have strikingly sharp contacts with the “inclusions”. Apart from these
rocks, numerous other varieties of granite also occur in the form of bands and patches in the coarse
grained pink granite. The most predominant amongst these being the fine grained pink granite
(1e).which exhibits sharp contacts with the granite (1a). However, at a few places a narrow zone of
transitional rocks, have been developed at or near the contact of the inclusion and the granite.
Coarse grained grey granite (1b.).
In the area under report, this variety of granite, usually rich in ferro-magnesian minerals,
occurs as bands and irregular patches in the (i) northern part of the hill, 0.6 kms. south of Ghugsi, (ii)
0.6 kms. southwest of hill 1103, (iii) 0.1 km. west of Inspection Bungalow at Kachneo and (iv) 2 kms.
north of Rajapur and various other places. Most of the exposures of this rock are associated with the
coarse grained pink granites (1a) while a few occurs in the medium grained grey granites (1d). Near
Kachneo, the rock outcrops between the exposures of coarse grained pink granite and the amphibolitegranite (hybrid?) rocks. With the development of a few big crystals of felspar, the grey granite passes
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to a porphyritic variety, as seen near Reyron Khirk.
Medium grained pink granite (1c).
Small exposures of this rock are noticed at many places in the area associated with coarse
grained pink granite (1a) and the medium grained grey granites (1d). The variety of granites usually
carries a few grains of ferro-magnesian minerals. Some of the important exposure of this rock are seen
(1) at a place 0.6 kms. north-west of Umri, (ii) in the hillocks north-east of Arjar, (iii) 1.6 kms. southsouth-east of Ghurari and (iv) 0.6 kms. north-east of Pua. At some places, e.g. (i) 0.4 kms. east of
Dharampura and (ii) 1km. south-west of Arjar, the medium grained pink granite is rich in ferromagnesian minerals.
Medium grained grey granite (1d)
This variety of granites, which is second only to the (1a) in a real distribution in the area, is
associated with the medium grained pink granite (1c). In general the ferro-magnesian mineral content
in the rock is low. At many places the rock is found to bear a few grains of felspar and ferromagnesian
minerals of slightly bigger size than the groundmass. At some places the rock occurs in the form of
bands.
Associated with the granites are seen a number of lenticular and lobate masses of pegmatites
(1.5 to 1.8 metres in diameter) composed mainly of felspar and quartz. Such bodies are very well seen
in the north-western part of the area. Due to weathering, pieces of quartz and felspar stand up
prominently on the rock surface. The medium grained grey granite is found to occur, though rarely,
within the coarse grained pink granite (1a). A few of the important localities where such occurrences
are encountered being (i) near Umri and (ii 0.8 kms. south east of Rampura.
At a few places e.g. (i) near Tejpura and (ii) south of Jakhangaon, the medium grained grey
granite is porphyritic with the phenocrysts (?), ranging upto 2.5 cms. across. The Jakhangaon
exposure appears to be a local variation of the coarse grained pink porphyritic variety (1a).
The medium grained grey granite is usually unfoliated. Mylonitic bands are also very rare.
The inclusions commonly seen in the rock are the granulites (?) and the hornblendic rocks.
The granite sends off minor bands and veins into these inclusions. Apart from these, like the coarse
grained pink granite, numerous bands of fine grained pink granites (1e) running for several furlongs
are found occurring in the medium grained grey granite.
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Fine grained pink granite (1e).
Amongst the fine grained granites, the pink coloured variety predominates The fine grained
pink granite occurs in two forms viz, (i) as dense compact rock and (ii) as granular rock. In the latter
case the rock contains slightly greater amount of ferromagnesian minerals than in the former. It is
mostly developed within the coarse grained pink varieties and may be just a fine grained facies of the
same.
The dense fine grained pink granite occurs usually in the form of long bands and in some
cases as irregular patches. Most of these rock seen to bear sub-rounded to rounded ovoids of felspar
and ferromagnesian minerals. The ovoids range in size upto 1.2 cms. across. At places the felspars are
lath-shaped. In a few of the bands the ovoids are seen at or near the contact with the enclosing granite.
At many places, the fine grained pink granite (slide No. 137) is associated with a few small
bands and lenticular patches of dark grey quartzites (slide No. UPP 123). Near Khisni Buzurg the dark
grey quartzites appear to mark the junction between the coarse grained pink granite (1a) and the fine
grained pink granite. Gradation from the dark grey quartzite to the fine grained pink granite, usually
absent, the contact being generally sharp. In a few of the bands, however, a transition (slide No. UPP
125) between the quartzite and the fine grained pink granite is seen. The frequent association and
mode of occurrence in the field, of the dark grey quartzites and the fine grained pink granite, as well
as their textural resemblances would tend to suggest that the fine grained pink granite might possibly
be genetically connected with the quartzites. More detailed petrological work would, however, be
necessary to proves this.
Fine grained grey granite (1f).
It is very subordinate in occurrence and is noticed near Ghugsi where it forms the tops of
knolls, seldom exceeding more than 15 metres across in size. The medium grained grey granite also
changes locally to the fine-grained grey variety. The ferro-magnesian mineral content in the granite is
usually very low.
Petrography
The granitic rocks of this region commonly display a hypautomorphic granular texture and
contain felspars (of different varieties) quartz, mica and chlorite with accessories like hornblende
magnetite, sphene, epidote, apatite and zircon.
Felspars, commonly seen, are K-felspar, Microcline, perthite and albitic-plagioclase. These
occur in subhedral to anhedral crystals. The potash felspars occur in bigger crystals and frequently
show sutured margin. They include laths of plagioclase and quartz. A few veinlets consisting of quartz
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and mica traverse the felspars. The felspars are usually altered. The plagioclase felspars are usually
more altered than the K-felspars. The marginal parts of some of the grains are fresh whereas the core
is highly altered. In the fine grained varieties, the felspars are somewhat more fresh than those in the
coarser grained types. Myrmekitic intergrowth of quartz and felspar is seen at some places, between
potash-felspars and the plagioclases.
Quartz grains are anhedral and occur in a mossaic of polygonal outline. Effects of crushing in
the form of granulated appearance and the wavy extinction of quartz granites are noticed at times
Mica (biotite) occurs in thin flakes and shreds; pleochroic from pale brown to dark brown and
pale brown to dark green. The crystal boundary is very irregular and some of these have embayed
margin. A few grains are poikilitic, including smaller grains of quartz and felspar. A large number of
magnetite grains are scattered in the biotite. Sometimes: the magnetite grains are rimmed by a thin
zone of sphene.
Sphene occurs in subhedral to anhedral grains and is frequently associated with magnetite.
Subhedra of epidote are scattered in the mass either as discrete grains or in crystal aggregates. Apatite
occurs in euhedral crystals enclosed in the felspars, quartz and mica. Zircon is less common and is
usually included in quartz and mica
INCLUSIONS
General
The granites bear a host of inclusions varying in sizes from a few cms. to more than 1.5 kms,
by 0.1 km.
These inclusions usually occur in the form of bands and as irregular patches. The bigger of
the inclusions roughly trend in two main directions; (i).ENE-WSW and (ii) WNW-ESE. There are
smaller inclusions with varying trends. Some of the inclusions are of hybrid nature resulting possibly
from the intercalation with the granites.
The inclusions found in the area can be grouped into 5 categories:1) Amphibolites and allied rocks,
2) Quartzites and allied rocks,
3) Granulites (?) and allied rocks,
4) Dark to light grey hornblende granites
5) Hornblende-biotite schists.
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These are described below:Amphibolite and allied rocks:
These are coarse grained hornblende rich rocks, with varying amounts of felspars of both pink
and grey colour. With the increase in the content of felspars some quartz and biotite also appear.
Some of the variants of this suite of rocks may apparently be termed as hornblende- rich granite. The
acidic varieties are seen mostly in the medium grained grey granite (1d).
Some textural variations have also been noted in the amphibolites. West of Marori some of
the inclusions are fine grained granular in texture.
The bands of amphibolites vary in sizes, between a few cms. square to two to five sq. kms. A
typical exposure of amphibolite is seen about 1.6 kms. WSW of Teharka. The band is roughly
0.2.kms. in width and 0.4 kms. in length and consists almost entirely of coarse-hornblende with a little
amount of interstitial felspar. In all the other exposures felspars form more than 50% of the rock. In
these rocks are seen a few lenticular schistose bands rich in hornblende ranging upto 6 metres across
in size.
The amphibolites are occasionally banded with alternate layers of hornblende and felspars.
This feature is well encountered in an exposure, 2.5 kms. west of Teharka.
Occasionally the amphibolites are intruded by veins of granite. At places, e.g. (i) 1.6.km.
WSW of Asati and (ii) 0.6 km. west of Marori, they occur in the form of angular blocks ranging upto
0.3 to 0.6 metres in length embedded in a matrix of granitic matter. Clots of hornblendic masses are
seen strewn over the surface of granites at many places. Those possibly represent the unassimilated
portions of what might have been the once continuous amphibolite bands.
The boundary of the amphibolite and the granites, in general, is sharp; transition zone has
been noticed only rarely, Near Teharka, however, a transition zone, roughly 7.5 cms, wide, is
developed between the inclusion and the host rock.
The amphibolites occurring as inclusions are broadly of three types. The purer variety through
an intermediate type-containing many minerals common to both the inclusions and the host rock
granite, passes ultimately to an almost granulitic rock rich in ferromagnesian minerals.
The purer variety (coarse grained amphibolite) (slide No. UPP 120) shows in thin section
abundant grains of hornblende and a little amount of felspar. Hornblende occurs in large subhedral
crystals and is pleochroic from pale to dark green. It is partially altered to chlorite, epidote and zoisite.
Inclusions commonly seen in hornblende are apatite and sphene. Felspar is interstitial between the
grains of hornblende and in some cases is seen to fill up fractures in hornblende. The varieties of
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felspar observed in the rock are the same as seen in the enclosing granite i.e. K-felspar, microcline and
albitic-plagioclase. But the felspars in the inclusion are less altered than that of the host rock, where
those are often
The other varieties of coarser amphibolite (slide No. UPP 121) are characterised by the
presence of plenty of felspar and biotite apart from dominant hornblende. A few of these biotite flakes
are bent. A large number of small inclusions of apatite are seen in the felspar and the ferro-magnesian
minerals. Magnetite occurring as subhedral grains are in plenty and a few of them are rimmed by
sphene. Felspars are mostly altered. A few grains of quartz also appear in some cases.
At other end the rock is granite (coarse grained-slide No. UPP l22) (rich in hornblende and
biotite). But for the abundance of ferro-magnesian minerals this rock in thin section resembles the
coarse grained pink granite.
The suite of rocks vary in compositions from amphibolite to hornblende granite and possibly
resulted from the action of the granite, and the amphibolite. More petrological work would be taken
up in near future for the precise nomenclature of various varieties of these rocks.
Quartzite and allied rocks
Inclusions of quartzite found in the granite, are fine grained, dense and compact rock of dark
grey colour. The rocks weather giving rise to smooth surface.
Quartzites often are studded with sub-rounded to rounded grains of felspars, ferro-magnesian
minerals and quartz. The quartz ovoids are rare and have been seen in only a few bands. The felspar
ovoids range upto 0.6 cms. across and are both of pink and grey variety. Some of the ovoids are
fractured.
The quartzites locally at the contact with the granite are fine grained granular with the
development of the large number of small grains of felspars.
A few of the bands show a transition between the grey quartzite and the fine grained pink
granite. These transitional rocks are pinkish grey in colour and contain very small grains of felspar in
fair concentration, in the matrix.
In thin section the rock (slide No. UPP 123) displays a granoblastic texture with quartz and
felspar (few) forming a mosaic of polygonal grains in which are scattered varying proportion of
hornblende and biotite. Magnetite grains are also abundant and are associated with crystals of ferromagnesian minerals. Epidote grains are few. The ferro-magnesian minerals show in some cases
preferred orientation.
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A few of the specimens of quartzite (slide No UPP 126 & 127) under microscope show some
subrounded grains of quartz and subhedra of felspar. The quartz has an irregular outline. A few of
them are broken and are filled with minerals of the ground mass. Granulation due to shearing is very
well displayed. The felspar porphyroblasts are partially altered. They constitute K-felspar, microcline,
perthite and albitic plagioclases.
The granular rock (slide No. UPP 124) occurring at the contact of granite and quartzite shows
good development of’ felspars many of which appear to replace quartz. Consequently quartz develops
embayed margin. The felspars are easily altered.
The pinkish grey transitional rock (slide No. UPP 123) under the microscope shows abundant
grains of felspars some of which occur as porphyroblasts. The texture of the ground mass is granular
resembling that of the quartzites.
Granulite (?) and allied rock:Megascopically these rocks may be grouped into two classes-(i) bluish grey dense rock and
(ii) light coloured biotite rich granular rock. The former resembles the dark grey quartzite but with a
bluish shade of colour. The rocks of both the classes are characterized by (i) a generally characteristic
weathering with crests and troughs of small dimension on the surface and (ii) being intruded by
numerous bands of medium grained grey granite. (1d).
The bluish grey dense rock occurs in the form of bands usually 61 metres in length within
both coarse grained pink granite (1a) and the medium grained grey granite (1d).
The light coloured biotite rich granulitic rocks are usually found associated with the medium
grained grey granite and are rarely found within the coarse grained pink granite. The ferro-magnesian
minerals in the rock display foliation concordant with the regional foliation observed in the area.
The study of thin sections reveals that the rocks are of hybrid nature resulting from the interaction of’ granite and granulite and gradation from partially digested granulite to hornblende- biotite,granite is observed. The bluish grey compact rock (slide No. UPP 128) is the least digested and under
microscope displays a granulite texture. It is composed dominantly of felspars which are seen to
enclose irregular grains of quartz, mica, chlorite, and iron ore. The felspars are highly altered, its
outline is very irregular being cuspate towards felspar and embayed-towards quartz. In some cases the
cracks in quartz have seen filled up by altered felspar.
The granular variety, in thin section (slide No UPP 129-131), differs from the bluish-grey
compact rock in containing more of the quartz grains and the ferro-magnesian minerals. The grain size
grows bigger and the outline of quartz tends to be more regular but still the embayed margin is seen in
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some of the grains. The texture is granulitic. Amongst the ferro-magnesian minerals, hornblende
dominates over the biotite. A few of the rocks of this group simulates granitic character exhibiting
hypautomorphic granular texture. The felspars which in other cases are irregular are now mostly
subhedral. In certain portion of this slide the relict granulitic texture is also noticed.
Hornblende granite
The rock is of dark to light colour and resembles some of the granulitic rocks and may range
in composition from hornblende granite to granodiorite. It is fine grained granular and contains plenty
of rounded clots of ferro-magnesian minerals. Bands of the dark coloured rock have been seen at (i) 2
kms, of south-west of Rauli and (ii) 0.8 kms. north-east of Sakrar. The light coloured rock occurs near
Nora and Sakrar and some other places.
The rock (slide No. UPP 132 to 135) differs from the ordinary granite in containing more
hornblende with irregular outline and sieved with inclusions of quartz and felspar. At places it is
interlaminated with biotite which is developed mostly at the edges. Many of the grains of the felspars
are idiomorphic and in this way can be distinguished from the other hybrid granites (resulting from
the assimilation of granulites).
Hornblende-biotite-schist.
It is very isolated in occurrence and has been found to occur in small patches ranging upto 3
metres across within the medium grained grey granite (1d) at a place about 2.5 kms. from Gidkhiri. It
is intruded by thin veins of medium grained granites.
The thin section (slide No. UPP 136) of the rock shows a good preferred orientation of the
ferro-magnesian minerals. The rock is composed of quartz, hornblende and biotite. A large number of
zircon grains are scattered all over the mass.
QUARTZ REEF
The area is traversed by a large number of quartz reefs. Excepting a few, majority of these
trend in NE-SW direction. Some of the reefs have ENE-WSW and NW-SE trends. The reefs vary in
width from about half a metre to as much as 60 metres. These have been traced, discontinuously, for
many kilometres. Reefs, at times, show a change in the direction of strike or offsets. Individual reefs
sometime branches into two
A really the quartz reefs are concentrated in three well defined zones, as parallel to subparallel bands; the zones varying in width from about 0.2 kms. to 0.8 kms.
The reefs are made of composite masses consisting of fine grained dense quartz grains of
12
GSI-CHQ-802
greyish white to pale pinkish Colour, veined by milky white secondary quartz trending in the NW-SE
direction in the major reef. The biggest reefs are frequently crushed and brecciated. These are
associated with ferruginous matter at some places. About 1.8 kms. WNW of Asati, on the northern
flank of the hills made up of quartz reef, is seen a zone of ferruginous clay (sometimes sandy),
roughly 60 metres in length, where the thickness of the reef dwindles down to roughly 0.6 metres.
South of this ferruginous zone the quartz reef is again seen in great force, attaining considerable
thickness.
The contact of the major reef with the granite is seldom exposed, being hidden under the
debris of quartz, and the granites are very rarely seen.
Two sets of joints are prominently developed in the reef-(i) NE-SW (parallel to the trend of
the quartz reef ) and (ii) NW-SE, at right angle to (i). The joints at some places are filled with epidote
which may be lined with thin zones of silica.
The views of Dr. Misra (The quartz reefs of Bundelkhand granites and their origin;” Proc.
47th Indian Science Congress: part III, pp. 241-42), that the quartz reef may not be igneous but are
recrystallised quartzites does not appear to fit in well with the field data. One of the evidence cited by
him is the uniformity of trend of quartz reef which represents the original disposition of the rock. If
this be the case then the other associated members of the sequence should also be aligned in a roughly
parallel trend. Field evidences are against this. The quartz reef appears to cut the general trend of
inclusions.
PEGMATITES
As compared with the quartz reefs, the pegmatites are very few in this area. Most of these are
1.5 cms. to 23 cms. in width and run for a few tens of decimetres in varied directions. They are
composed of quartz and felspar.
The pegmatite found at a place about 1.8 kms. south of Billat is circular in plan measuring 60
metres in diameter. The felspar and quartz crystal of which the pegmatite is composed are elongated
in the vertical direction. From the surface examination the shape of the pegmatite body appears to be
of the nature of the pipe
DOLERITE DYKES
The granites are cut by a large number of dolerite dykes trending generally in the NW-SE
direction. The band varies in width from a few decimetres to about 0.1 km. and have been traced
discontinuously for several kilometres. Intrusive relation with the granite is evident from the clear
development of the marginal fine grained facies of dolerite. The dolerite near the contact sends out
13
GSI-CHQ-802
thin veins and apposes in the granite. The relative age of the quartz reef and the dolerite dykes is not
clear in the area since these are seldom seen in contact with each other. At a distance of about 0.8
kms. north of Naykhera, a dolerite dyke is seen apparently cut by a quartz reef. More detailed search,
however, revealed that the two parts of the dolerite dyke on either side of the quartz reef are joined by
discontinuous patches of dolerite seen in the reef which could also suggest that the quartz reef is cut
by dolerite
STRUCTURAL GEOLOGY
The data so far collected during the course of geological mapping, is not sufficient to visualise
accurately the regional structure of the area. However, the significant structural features encountered
in the field work are briefly recorded here.
Strike-trend of “inclusions”.
In general there are two major directions in which the inclusions are aligned-(i) ENE-WSW
and (ii) WNW-ESE, the former trend is prevalent mostly in the northern part of the mapped area and
also to the west of the Rajapur quartz reef. Some of the quartz reefs here have also the same trend.
The other trend is seen in the southern part of the area where a few of these bands also show the
former trend. Deviation from these two major trends are noticeable in some of the bands to the south
of Khisni Buzurg,
Foliation
Foliation is very weakly developed in the rocks of the area. On the surface it is due to
elongation of quartz grains and the parallel orientation of the ferro-magnesian minerals. The general
trend of the foliation is N 60ºW-S 60ºE., the dips of the foliation in many cases are not easily
discernible. The foliation, where ever well developed, is steeply dipping (above 60°) on both sides.
This foliation direction is common both in the granite and inclusions. Near the contact of the mylonite
band the granite is locally foliated usually making a small angle with that of the mylonite band but
when traced towards the mylonite, in many cases, the foliation of the granite has been found to merge
with that of the mylonite band.
Joints
Though there is a wide variation in the directions of jointing in the granite, the sets commonly
seen are (i) WNW-ESE to NW-SE and (ii) NE to SW to ENE-WSW. In many cases a horizontal
jointing with very shallow dip in varying directions, is also developed.
These sets of joints are common both to the granites as well as the inclusions. In the fine
grained granite, the joints are more closely spaced than the coarse grained variety.
14
GSI-CHQ-802
GENERAL REMARKS
Granite with its various problems has been the concern of geologists for more than a century.
But there still holds today, even after such a large amount of work done in this field, a wide diversity
of opinion between the various workers regarding the origin and emplacement of granite. So far as the
granite problem in present area, is concerned, I am not in a position to give any view as the field
studies were not substantiated by enough laboratory work. The laboratory work consisted only of the
preliminary examination of a few slides of the typical rock types. However, it will not be out of place
at this stage to put some of the more salient points of my observations which may be relevant to the
problem of origin of these rocks.
1. The coarse-grained pink granite (1a) bearing some ferro-magnesian minerals and the
medium grained grey granite also with some ferro-magnesian minerals (1d) are the two dominant
types of granites encountered in the area. The coarse grained pink granite occurs in the south-eastern
part of the area, where medium grained grey granite is very subordinate in occurrence and the latter
rock is developed mainly in north-western part, where the coarse-grained pink granite so typical in the
south-eastern part, is rarely seen. The occurrence of these two types of granites, without any marked,
association or any passage from one to the other may perhaps indicate that these two are of different
generations.
2. One set of inclusions, granulites (?), is cut, in most cases, by medium trained grey granite
even when these are enclosed by coarse-grained pink granite. The bands of medium grained grey
granite does not extend from the inclusions to the coarse-grained pink granite. This would indicate the
possibility of the medium grained grey granite being of earlier origin.
3. The contacts between the inclusions and granites are commonly not gradational and no
where the inclusions are seen to merge imperceptibly to the adjoining granitic rocks.
This fact would be against the metasomatic origin of granites.
4. Evidences of reaction between the granites and the inclusions have been seen at many
places. The different bands of hornblendic rock show varying proportion of quartzo-felspathic
material. In the purer band the interstices between the hornblende are filled by felspar which are
identical to that seen in the enclosing rock. As the proportion of quartz and felspar in the hornblendic
rock increases biotite starts taking the place of hornblende often at the expense of it, which is in
conformity with the Bowen’s assimilative reaction principles (Igneous and metamorphic petrology;
Turner and Verhoogen-pp.75). The granite in the vicinity of inclusion is enriched in hornblende.
5. The dark grey quartzite locally shows evidence of replacements, by felspar and quartz
grains. It is probable that some of the inclusions have been locally metasomatised by the granite.
15
GSI-CHQ-802
6. The fine grained pink granite bearing ovoids of felspars and ferro-magnesian minerals, at
many places are associated with small and thin bands of grey quartzite. At places the quartzite occurs
at the margin of the fine grained pink granite and the host rock granites. In a large number of cases the
fine grained pink granite occur as independent bands. A few of these bands show transition stage
developing between quartzite and the fine grained pink granite. The contact between the fine-grained
pink granite and the other normal granite is strikingly sharp and this suggests that many of fine
grained pink granites represent a separate phase of activity in the complex igneous history of
Bundelkhand granites. It, however, remains to be worked out whether they are earlier or later than the
normal prevalent granite of the area. The fine grained pink granite needs careful studies because
normal microscopic work is rendered difficult on account of the fine grin size.
ECONOMIC GEOLOGY
Amongst the economic minerals and rocks the following are worth mentioning:-(i) Sulphide
minerals, (ii) Pyrophyllites and (iii) Road metals and railway ballasts. Excepting the road metals and
railway ballast the occurrences of other minerals are not large enough to warrant economic
exploitation.
Sulphide minerals
Specks of pyrites have been noticed in the different varieties of granites as well as in the
inclusions but these are only of mineralogical significance. South of Bhimaura on the northern side of
the railway line chalcopyrite in association with pyrites forms bunches and nests ranging upto 7.5
cms. across within the coarse grained pink granite, rich in ferro-magnesian minerals. It is very
localized in occurrence. The exposures bearing these pyrite and chalcopyrite bodies do not exceed 3
metres across in extent.
Pyrophyllite
Pyrophyllite occurs associated with quartz reef and has been located near Rajapur. The exact
extent of the deposit is difficult to estimate since the area is covered under alluvium. They are
concentrated in two zones-(i) 0.3 kms. ESE of Rajapur and, (ii) 0.4 kms. NE of Larwari. In the former
locality this appears to be localized in an area not exceeding 90 metres x 60 metres. The Larwari
deposit appears to be very small. A few shallow pits covered with debris occur in the zone of
pyrophyllite.
The pyrophyllite is yellowish grey and purplish in colour and greasy in feel. In hand
specimens it resembles soapstone and shows faint foliation.
For several metres along the trend of the quartz reef smears of pyrophyllite are also seen near
16
GSI-CHQ-802
the zones of concentration of pyrophyllite bands. At many places it occurs intergrown with quartz.
Though a few bands may occur within the quartz reef, it would appear that the major bands
are concentrated towards the contact of quartz reef and granite. It is probable that the contact might
have acted as a control for the formation of pyrophyllite.
The Rajapur pyrophyllite is not being used, Pieces of this mineral are collected by the
children for use as slate pencil.
Road Metals and Railway Ballasts
Vast supplies of this material exist in the area. The dolerites, fine grained granites and quartz
reefs are the good sources of road metal and railway ballasts on account of their hard and compact
nature and fine grained texture.
WATER SUPPLY
The main source of water supply of the area are wells and tanks. Wells are usually shallow
varying in depths from 3.0480 metres to 12.1920 metres. The depth to water level is usually shallow
in the coarse-grained granite; whereas it is deeper in the fine-grained types. The upper weathered zone
of coarse-grained granite forms a good receptacle for groundwater; while in the fine grained granite
groundwater is mostly localized along the joint planes.
LOCALITY INDEX (Sheet No. 54 K/15).
Locality
Co-ordinates
Arjar
25º19c40s
:
78º49c27s
Asati
25º23c20s
:
78º51c00s
Bhimaura
25º23c00s
:
78º53c00s
Billat
25º18c55s
:
78º45c10s
Churari
25º17c50s
:
78º52c50s
Dharampura
25º17c30s
:
78º48c20s
Gidkhini
25º24c20s
:
78º48c30s
Ghugsi
25º19c20s
:
78º57c15s
Hill 1103
25º17c00s
:
78º59c00s
Jakhangaon
25º16c00s
:
78º56c15s
Kachneo
25º16c00s
:
78º58c30s
Kagar
25º15c05s
:
78º58c00s
17
GSI-CHQ-802
Khisni Buzurg
25º16c30s
:
78º50c00s
Larwari
25º15c50s
:
78º45c05s
Marori
25º20c20s
:
78º47c15s
Nanora
25º18c00s
:
78º48c00s
Naykhera
25º18c40s
:
78º46c20s
Nivari
25º21c00s
:
78º48c00s
Nora
25º19c55s
:
78º53c55s
Pua
25º20c50s
:
78º60c15s
Rajapur
25º16c15s
:
78º45c30s
Rampura
25º18c20s
:
78º50c30s
Reyron Khirk
25º15c25s
:
78º55c00s
Sakrar
25º21c15s
:
78º52c30s
Teharka
25º17c15s
:
78º53c10s
Tejpura
25º19c40s
:
78º58c10s
Umri
25º18c40s
:
78º56c00s
Yobri Khirk
25º15c00s
:
78º53c00s
18
GSI-CHQ-802
BIBLIOGRAPHY.
Hacket, C.A. (1870)
Geology of Gwalior, Records, G.S.I. Vol III., Part-2,
Medlicott, H.B. (1859)
On the Vindhyan rocks, and their associates in Bundelkhand
Mem. G. S. I., Vol. II., part-1.
Jhingran, A. G., Mathur, S.M., Puri, S.N. and Progress report for the year 1953-‘54. A study of a part of the
Sharma, R.S. (1955,)
Bundelkhand granites and gneisses.
Jhingran, A.G (1958)
The problem of Bundelkhand granites and gneisses, presidential
address, Forty-fifth Indian Science Congress
Puri, S.N. and Mathur, P.C, (1958).
Progress report for the year 1957-‘58 study of Bundelkhand
granites and gneisses
Sd/
(H.N. Singh)
Geologist,
Geological Survey of India,
U.P.-Punjab Circle,
Lucknow.
‘Sharma’
7.10.61