Geological Fieldwork File

FIELD REPORT ON ANNUAL GEOLOGICAL FIELDWORK
Submitted To-
DEPARTMENT OF EARTH AND ENVIRONMENTAL SCIENCE
KRANTIGURU SHYAMJI KRISHNA VERMA KACHCHH UNIVERSITY
SUBMITTED BY-
Mr. DHEERAJ SINGH
M.Sc. SEMESTER 1

KRANTIGURU SHYAMJI KRISHNA VERMA KACHCHH
UNIVERSITY
(A STATE UNIVERSITY ESTABLISHED UNDER ACT NO. 5, 2003,
BY GOVERNMENT OF GUJARAT)
CERTIFICATE
This is to certify that Dheeraj Singh of M.Sc 1st
Semester of the Department of Earth and Environmental
Science, K.S.K.V Kachchh University has completed the
field work in metamorphic terrain of North Gujarat and
Rajasthan region conducted from 20th September, 2019
to 30th September, 2019 is an authentic work carried out
under our supervision and guidance.
Teacher's Incharge –
Dr. Mahesh G. Thakkar
Dr. CP Mistry
Dr. Gaurav D. Chauhan

ACKNOWLEDGEMENT
It is my great pleasure and privilege to acknowledge all those involved directly or
indirectly from whom I received considerable help in this work. I take this
opportunity to thank all of them.
I am heartily thankful to Prof. Dr. Mahesh G. Thakkar, Department of Earth and
Environmental Science, K.S.K.V Kachchh University for his guidance. His constant
supervision, suggestions and discussions at every stage have enriched my work.
I would also like to extend my thanks to Assistant professor Dr. Gaurav Chauhan,
Dr. C.P Mistry.
A special thanks goes to our seniors Mr. Anil Chavan, Mr. Abhishek Lakhote, Mr.
Chirag Jani and Mr. Adarsh Thakkar who gave us a brief knowledge and made the
experience even more fulfilling.
I feel vastly enriched after spending our busy days in their company and consider
myself extremely blessed and lucky to have got this opportunity.
And at last, I'd like to extend my special thanks to all my friends whose cooperation
and help during the field is ought to be noticed without whom the field work
would be incomplete.
Date: 8th
October, 2019 Dheeraj Singh
M.Sc 1st
Semester
Department of Geology
K.S.K.V KACHCHH UNIVERSITY, BHUJ

Day Date Location
General Geology of Ambaji & Rajasthan
Day -1 20/09/19 A- Palanpur danto highway, Jalotra village
B- Nawabas, Near Hanuman Temple
Day-2 21/09/19 A- Kui Village Chitrasani
B- Balaram, Near balaram river
C- North Dabela
D- Shikanwadi
E- Kanpura
F- Kingora village
G- 3km east in Kingora village
Day-3 22/09/19 A- Near mandali village
B- Manik nath caves
C- Nani tundadiya
D- Dadadu
E- Nawabas, Danta highway
F- Pipalavali vav
Day-4 23/09/19 A- Vk trivedi marble mines, jariba village
B- Surphagla
Day-5 24/09/19 A- Tulsi das ji ki sarai village, near dewari
B- Near Debari, Opp. Of circuit house
C- NH-27, near chunda mahila college
Day-6 25/09/19 A- Jamunio ki naal
B- Near iswal village, near iswal highway
C- Jharmeshwar mahadev temple
Day-7 26/09/19 A- 45km NE of Udaipur Newania
B- Rundera Village
C- Bhojunda Stromatolites park
D- The great boundary fault
E- Chittorgarh fort

Day Date Location
Day-8 27/09/19 A- Jhamar kotra Phosphate Mines
Day-9 28/09/19 A- Haldighati road cutting section
Day-10 29/09/19 A- Road cutting section towards Mount Abu
B- Mount Abu Road (Road cutting section)

General Geology of Ambaji basin, delhi supergroup,
Northeast Gujarat
INTRODUCTION
Delhi Supergroup (DSG) occurring in the western part of the Aravalli -Delhi Mobile Belt of NW
India consists of low to medium grade rocks with sporadic occurrences of granulites. Unlike other
granulite belts of Indian Peninsula which occur as extensive manner namely Southern Granulite
Terrane and Eastern Ghats Mobile Belt, the granulites of DSG occur as discrete outcrops within the
low to medium grade rocks bounded by ductile shear zones. Additionally many ductile shear zones
occur within the granulite pocket suggesting the fact that the exhumation of such high grade rocks
has happened due to thrusting. Study of deformational structures in the low and high grade rocks
around Ambaji, Gujarat reveals that both the terranes have undergone similar deformational
history. In this paper we have discussed the deformational history of the low grade rocks
occurring in the Ambaji basin and comparison has been made with structures described from the
adjoining granulite rocks by Biswal et al., 1998a,b; Sarkar and Biswal, 2005; Singh et al., 2010.
REGIONAL GEOLOGY
The DSG forms a NE-SW linear belt on the western flank of the central part of the Aravalli mobile
Belt and fans out towards south and sprawls in the northern part, the northern part is called North
Delhi Terrane (NDT) and the southern and central part is called South Delhi Terrane (SDT). While
the NDT shows Mesoproterozoic age, the SDT shows Neo-proterozoic age. The Aravalli Mobile
Belt (AMB) is flanked by the Marwar and Mewar Cratons in the west and east respectively. The
Mewar Craton is comprised of Mesoarchaean tonalite-trondhjemite-granodiorite (TTG) gneisse
sand sporadic greenstone belts. However, the Marwar Craton is extensively intruded by the
Erinpura and Malani granites, and at several places has been covered by younger volcano-
sedimentary sequences belonging to the Sindreth, Punagarh, and Marwar groups. Therefore,
vestiges of the basement are observed at restricted places (near Bar, Heron, 1953). However, so far
no Archaean isotopic age has been reported from Marwar Craton. The AMB, consists of a collage

of NE-SW trending terranes namely Aravalli, Hindoli-Jahajpur, Sandmata-Mangalwar, Delhi and
Sirohi terranes. These terranes are constituted of thick sequences of Proterozoic meta-sedimentary
and meta-igneous rocks unconformably overlying the basement gneisses and individual terranes
display marked contrast in their deformational history.
The Aravalli Terrane is Palaeoproterozoic age and is represented by low- to medium-grade rocks
showing multiple phases of folding and granitic intrusions. Shallow water stromatolites bearing facies
occur in the east and deep water carbonate-pelite facies are present in the west having been separated
by the ophiolite-bearing Rakhabdev subduction zone. The Hindoli-JahajpurTerrane is represented by
very low grade pelitic and felsic volcanic rocks and probably belongs to Proterozoic age. The Sandmata-
and MangalwarTerranes are dominated by Archaen age migmatitic gneisses with sporadic enclaves of
amphibolite and metapelite within it probably belonging to a greenstone sequence.
Granulite pockets have been emplaced into Sandmata terrane at around 1.7 Ga. The Sirohi
Terrane is Neoproterozoic age and occurs to the west of the SDT, and consists of low grade
metasedimentary rocks. The terrane is extensively intruded by the Erinpura granites, Malani igneous
suite and Sindreth volcanic. The SDT has been divided into number of longitudinal tectonic zones; the
eastern zones are dominated by arenaceous facies while the western zones are dominated by
calcareous facies. The SDT is marked by greenschist to amphibolite facies metamorphism
and multiple stages of folding, however, at places granulite, tectonic slices of ophiolite, blue schist
and basement gneiss occur within it.
Based on the ages of the synkinematic Sendra-Ambaji granite and diorite, the South Delhi orogeny
is constrained between ca. 1.7 and 0.8 Ga. The basin closed through subduction along the Kaliguman
shear zone running along the contact between the Delhi and Aravalli Terranes. Contrary to this, the NDT
exhibits more extensive outcrops of quartzites and schists unconformably overlying the sialic
basement rocks. The NDT is marked by late-stage open folding, axial planar shearing and low
grade metamorphism, and has been constrained to between 1.8 and 1.5 Ga.

Ambaji basin: rock types
The Ambaji basin is represented by low grade rocks comprising quartzite, amphibolite, calc schist,
mica schist and granite. Quartzites are interlayered with amphibolite band. They have very
distinct depositional bedding layers of different thicknesses. They are jointed, fractured, foliated,
occasionally sheared and massive. Under thin section, grains are medium to fine,
equigranular. Biotite, muscovite and quartz are the main minerals found in the quartzite band.
Amphibolite appears dark green medium to fine grained and well foliated. Under microscope,
actinolite-tremolite, hornblende, muscovite, biotite, quartz, K-feldsper are showing preferred
orientation. Poikiloblastic texture is prominent with growth of plagioclase and K-feldspar
porphyroblasts. In many cases actinolite and tremolite layers are finely interlayered with
thin carbonate layers dominantly consisting of calcite; as a result the whole unite is so called calc
schist. The calc silicate layers stand out prominently forming ribs due to differential weathering.
Under microscope, grains are of medium size more or less showing preferred orientation. In hand
specimen, mica-schists are fine to medium grained, dark, shiny with vitreous luster, highly
foliated. Schistose texture is defined by biotite and muscovite both in megascopic as well as
microscopic scale in mica schist, where biotite is the dominating mineral and the other constituent
minerals are muscovite, quartz and feldspar. Granites are massive, foliated and fractured
and are interlayered with calc schist. Granite consists of quartz, plagioclase, K-feldspar, boitite
and hornblende. Myrmekite textures are common in the granite.

Structures
• Small Scale Structures
The study area shows polyphase deformation history. Three phases of folding have been identified and
designated as F1, F2 and F3 respectively for first, second and third generations. The F1 folds are
tight to isoclinal and are developed on the bedding plane (S0 ) and gives rise to most prominent
schistosity (S1). S1 fabric crosscut the bedding plane (S0 ) at the hinge area of F1 folds,
but along the limb of the F1 folds S1 remains parallel to S0. In mica schist, amphibolite and quartzite S0
plane are well preserved as compositional banding but in calc schist it is defined by alternate
carbonate and calc silicate layer that represent original bedding plane. Isoclinal F1 folds are
recumbent to reclined to upright, showing very high amplitude to wavelength ratio and mostly fall
under the Class 1C fold of Ramsay's (1967) methods of fold classification. Under microscope S1
fabric is defined by shape preferred orientation of actinolite-tremolite, hornblende in amphibolite
and calc schist; biotite, muscovite and quartz in mica schist. Except intrusive granite body, all the
country rocks exhibit second generation of folds (F2 ) at various scales (Fig 3a, 3b, 3c, 3d, 3e). Upright to
incline F2 folds are open to tight, developed on the original bedding plane S0, and S1 planer fabric. F2
folds are also modified into box folds showing two hinges at the outer part and single hinge isoclinals
fold at the core (Fig 3a).
• Large Scale Structures
The map pattern of the study area is defined by the contacts between three groups of litho types viz.
quartzite/mica schist, amphibolite/ calc schist and granite. Granite is the lowermost unit
with amphibolites/ calc schist and quartzite/ mica schist over it. Contacts show effect of folding
throughout the study area. The contact between quartzite/mica schist and amphibolite/ calc schist
produce a synform at western part of the area. The eastern part of the area shows the presence of an
overturned antiform with granite at its core. The common limb of these two fold strikes NW SE
and dips moderate to steeply towards SW. Both the synform, and the overturned antiform show
general trend of dominat F fold being NW SE. Effect of F3 fold is most prominent on the contact
between quartzite/mica schist and amphibolite/ calc schist. The synform, defined by this contact
show the effect of F3 fold with conjugate axial trend trending NNW SSE and ENE WSW.

General Geology Of Rajasthan .
Every facet of rajasthan is unique and fascinating – so is its geology. Its rock range in
age from one of the oldest (more than 3200 million year age) to recent, displaying a wide
range of rocks, mineral deposits and geologic processes. Mining and smelting of its base
metals deposits are also one of the oldest in the world dating back to more than 2500 years
before present (BP). The states modern geological knowledge is based on mining interest of
British India Government (1829 onward),which had established Geological Survey of India
(GSI) – one of the first in the world. Culmination of GSI workers resulted in publication of
Memoir# 65 of GSI in 1936 and more significantly the Memoir# 79 (in 1953) with fairly
accurate and two-sheet maps that served as guiding maps for decades. The modern knowledge
of principles of stratigraphy , remote sensing , tectonics etc have been utilized in publications
of GSI Memoir # 123 in 1997 with four-sheet geology and structure maps (on 1:253,440
scale). Numerous university and State Government geologists have described geology of
specific sites. The status of geological knowledge of region at the end of the last century has
been concisely presented in text book “Geology of Rajasthan” by S.Sinha Roy, G.Manhotra
and M. Mohanty published by the Geological society of India, Bangalore in 1998.
Briefly stated, Rajasthan is endowed with a continuous geological sequence of rock
from the oldest Archaean Metamorphic, represented by Bhilwara Supergroup (>2500 m.y)to
sub recent alluvium & wind-blown sand. Vast unconsolidated deposits including the blown
sand of Thar Desert of Western Rajasthan cover the western & NW parts of the state. The
remaining area exposes wide variety of hard rock’s including various types of metamorphic
rocks like schist, quartzite, marble, and gneisses of Precambrian age with associated acid &
basic intrusive rocks. The formations include the rocks of Aravalli Supergroup, Delhi
Supergroup, upper Precambrian Vindhyan Supergroup and those of Cambrian to Jurassic,
Cretaceous, and tertiary ages. The southeastern part of the state is occupied by a pile of
basaltic flows of Deccan Traps of Cretaceous age. Several mineral deposits and renowned
building stones of economic importance occur in association with the above rock units.

Sandmata Complex (SC), the Mangalwar Complex(MC),and the Hindoli Group(HG),Forming
the Bhilwara Supergroup(BSG), is essentially Archaean in age. This is evident from ca 3.5 Ga
age of some mafic inclusions within the BGC and from the age of intrusive granite(2.9 Ga,
Untala and Gingla granitoids). Gneisses comprising the SC and the MC, represent the
reclassified Banded Gnessic Complex of Heron (1953). Rock types of the SC are composed
largely of granulites facies gneisses of diverse composition, such as metapilites and psammitic
gneisses, basic intrusives, and calcareous clastic and chemogenic metasediments which occur
as xenoliths, streaks and patches, and thrust bound large bodies in the gneissic terrain.
Although Gupta et al. (1981) have shown in their map of the Aravalli region that the SC forms
a distinct litho units which lies to the west of the MC, the SC occurs as tectonic wedges within
the basement gneisses of the MC.
The generalized geological succession of the Precambrian formation of Rajasthan after GSI
Memoir # 79 is given below:
Recent & Sub recent Alluvium and blow sand
Vindhyan System Sandstone, limestone & Boulder Dolerite and basalt
(age uncertain)
Malani Rhyolites Rhyolite, tuffs
Granite, ultrabasic rock
Erinpura granite,
Pergmatite, aplite
Epidiorite and
hornblende schist
Delhi
Ajabgarh Series Upper phyllite , Limestone, Biotitic
Limestone and calc-schist , Phyllites
, biotite schist and composite
gneiss.
System
Alwar Series
Qurtzites Arkose , grit and
conglomerates.
Raialo Series Garnetiferous biotite schist
Limestone (marble)
Local basal grit
Aploganite, epidiorites
and hornblende schist ,
ultrabasics
Aravalli
System
Impure limestone , Qurtzites
Phyllites, Biotite-Schist, Composite
gneiss
Qurtzites, grits and local soda-
syenites, conglomerate.
Local amygdaloids and tuffs
Banded Gneissic
Complex(BGC)
Schits , gneisses and Composite
gneiss
Qurtzite
Pegmatites, granites,
aplites and basic
roocks

GEOLOGY OF RAJASTHAN
Pleistocene- AJ1u’ñum/Blown san0
Eocene-I.Jandai/AkIi/Kapurdi/Jogira/fear/
Banda Khu a/Pa ana Series
Cretaceous-fibur/Fatehgarh Series
Ara’alli Sripergroup - Jharol/Bari/Udaipur/Debari Group
Bhilwara Sripergrorip - Ranthamdhor/
Rajpura-Dariba Hin0oli Group
Jurassic-Parihar/Badasar/Baisakhi/JaisaImer/Lathi Series * Msives / Extrusives
Permo-Car Coniferous - Badharira Series
l'1arwar Supergroup
Vindh’an Supergroup - Bhander Group
Vindhyan Supergroup -Rewa/Kaimrir/SemriGroup
Delhi Supergroup - Ajabgarh/AIwar/Sirohi/
Punagarh/Ftaialo Group
Deccan Trap
'da an Vocan cs on cs
Post Delhi & Synorogenic granites
TErinpura/Siwana/Sendra-Ambaji Granites)
Kishangarh Syenite
afics 8 Ultramafics
Berach Granite/Acidic, ltlafic & Ultramafic bodies
GroundWaterAtlasofRa t999
State Remote Sensing Application Centre, Department of Science end Technology,
Govt ofRe Jodhpur
Harshita Upadhyaya

Geology Around Udaipur: Rocks of Mewar Gneiss Complex and Aravalli
Supergroup
Generalised Stratigraphic Succession of the pre-Vindhyan rocks of Rajasthan was given by
Heron (1953) is as shown below.
Malani rhyolites, and
Jalore & Siwana granites
Erinpura granite
Puranas (=Algonkian) Delhi system
Eparchaean Interval Raialo series
I Post-Aravalli & pre-Delhi granitoids
I
Archaean I Aravalli system
I
I Banded Gneissic Complex, and
I Bundelkhand gneiss
************************************
BASEMENT ROCKS- AGE, EVOLUTION AND RECONSTITUTION
The basement rocks of Archaean age exposed east of Udaipur to Chittaurgarh are highly eroded
and forming almost flat terrains.Structural and geochronological studies indicate that a
considerable part of the Archaean basement has undergone tectono-thermal reconstitution, so
much so that it is now difficult to recognise Archaean features in these rocks. For the purpose
of detailed discussion, we shall classify the different basement rocks into three categories :
1. Mewar Gneiss Complex (MGC): the basement gneisses, which retained their pristine
Archaean character, remaining virtually unaffected by Proterozoic deformation and
metamorphism during the later orogenies.
2. Dominantly granitic rocks essentially of Archaean age, occurring as intrusive into the
Mewar Gneiss Complex (Untala and Gingla granites) or as inliers within the outcrops
of the Aravalli Supergroup.
3. The basement ensemble of gneiss-amphibolite-granitoid, which has undergone
tectono-thermal reworking during the Proterozoic. These belts will be described as
tectono-thermally reworked (TTR) basement.
Aerial distribution of all these different types/ categories of granitoids and gneisses are
shown in Fig. 1 and Fig. 2. Geochronological and tectonostratigraphic framework of the
Precambrian rocks of Mewar and Udaipur region is shown in table 1 and geochronology of
basement rocks is shown in table 2.

Fig.1. Geological map of southeastern Rajasthan showing aerial distribution of different categories of
basement separated by cover outcrops of the Aravalli Supergroup.
Fig.2. Generalised geological map of the area around Udaipur.

1. Mewar Gneiss Complex
The most instructive outcrops of the Mewar Gneiss Complex (MGC) occur east of Udaipur city near
Tulsi Namla temple. The recent isotopic studies indicate ‘pristine’ Archaean character of different rocks
constituting the Mewar Gneiss Complex.
Lithology
The Mewar Gneiss Complex is constituted of four main lithological units: (i) biotite
gneisses,(ii) amphibolites, (ii) metasediments, and (iv) ultramafic rocks. In addition to these four
lithologies there are also several bodies of granitoids, the large ones include the Gingla granite and
Untala granite. The biotite gneiss by far is the most extensively developed lithological component of
the MGC followed by granitoids. Metasediments and amphibolites follow in that order. Ultramafic
rocks occur very rarely.
(i) Biotite gneiss.
Biotite gneisses are typically grey coloured, characteristically showing prominent gneissic
banding. Earlier workers such as Gupta (1934) and Heron (1953) described these rocks as the
Banded Gneissic Complex, mainly because of this physical character. Where massive
granitoids (both leucogranite and pink granite types) occur close to biotite gneisses, the contact
between the two appears gradational.
Mineralogically, biotite gneisses are composed of quartz, feldspar (both microcline and
plagioclase feldspar in varying proportions), biotite and chlorite (a possible retrograde mineral).
(ii) Amphibolite
Depending on the nature of occurrences and petrographic characteristics the amphibolites
occurring in the Mewar Gneiss Complex can be divided into three different categories.
1. Amphibolites occurring as small enclaves of irregular shapes and sizes within biotite gneisses
and granitoids.
2. Large, relatively linear bodies of amphibolites showing complex outcrop pattern due
to superposed folding.
3. Actinolite bearing undeformed meta-basalts, cross-cutting even the youngest (~2.5 Ga old)
pink granite.
Most of the large bodies of amphibolites are schistose, mineralogically quite homogeneous, fine- to
medium-grained rocks. The amphibolites are composed predominantly of hornblende and plagioclase
(An30 to An40) with minor amount of quartz, chlorite, epidote, apatite, leucoxene and magnetite.
(ii) Metasediments
Metasediments present in the basement rocks include quartzites (usually greenish coloured with
chrome-bearing mica minerals), marbles, calc-silicate rocks, ironstone formations, and mica schists.

(iv) Ultramafic rocks.
There are a few enclaves of metamorphosed ultramafic rocks in the MGC. Two
different types of ultramafic rocks are encountered. The larger bodies are composed of tremolite and
actinolite with minor quantities of talc and opaque minerals. Talc-antigorite schist with or without
secondary carbonate and magnesite represents the other type.
2. Archaean granitoids
There are a number of late Archaean granitoids, which either occur as large bodies within the Mewar
Gneiss Complex or as separate bodies of granitic inliers surrounded by metasediments and
metavolcanics of the Aravalli Supergroup. Although, the mineralogical and petrological compositions
of these rocks do not always correspond to those of true granite, yet we prefer to describe these rocks
as ‘granite because these are already well-known in literature by that name. Two large bodies of granite
within the MGC are the Untala granite and the Gingla granite (Fig. 2). The major bodies of granite
‘inliers’ are the Berach granite near Chittaurgarh and the Ahar River granite near Udaipur. A
characteristic feature of all these granites is the coarse-grained porphyritic texture, without showing any
prominent foliation. Compositionally, these granites are typical leucogranitoids having very little mica
minerals.
Fig 3. Geological map showing lithostratigraphic relationship between basement
rocks and the basal Aravalli beds. Northwestern fringe of the outcrop of
the the Ahar River Granite.

Table 2. Geochronological framework for the Archaean basement of Rajasthan
Age (Ma)
2450 ± 8 #
Method used
signle zircon
Emplacement events
Berach Granite
2506 ± 4# do Vali River Granite (Jagat)
2505 ± 3# do Pink granite of Untala
2532 ± 5# do Jhamarkotra Granite
2562 ± 6# do Ahar River Granite
Shearing and low temperature metamorphism
2620 ± 5@ single zircon Gingla Granite
2658 ± 5@ do Jagat Granitoids
2666 ± 6@ do Untala trondhjemite (gneiss)
(enclave in the pink Untala
Granite)
Ductile deformation, repeated folding and metamorphism
2828 ± 46* Sm/Nd isochron age Intrusion of mafic dykes of Mavli
(=Jagat Type I amphibolites)
2887 ± 5 @ single zircon Banded TTG gneiss of Jagat
~3230 @ single zircon Intrusion of trondhjemite, folding
& formation of new foliation
3281 ± 3 $
to
3307 ± 65*
single zircon
Sm/Nd isochron age
Earliest igneous protoliths
of banded gneisses
of Jhamarkotra
PALAEOPROTEROZOIC : ARAVALLI FOLD BELTS
Regional distribution
The Aravalli Supergroup (Fig. 1) of Palaeoproterozoic age is the oldest cover succession, which
evolved as ensialic rift basins over the Archaean basement rocks. Considered to be geologically
interesting with bountiful of mineral deposits, the rocks of the Aravalli Supergroup (described
by Heron, 1953, and other contemporary geologists as ‘system’)
# Single zircon ion-microprobe U-Pb age ( Wiedenbeck et al. 1996a)
@ Single zircon (evaporation) age (Roy and Kröner , 1996)
* Sm-Nd whole-rock isochron ages (Gopalan et al. 1990)
$ Single zircon ion-microprobe U-Pb age (Wiedenbeck and Goswami, 1994)

attracted attention of a large number of geologists for the last hundred years or so.
Nevertheless, the geologists working in this region are divided on questions of age, aerial
extent, internal stratigraphy and the basement-cover relationship.
For convenience of tectono-stratigraphic description, the terrane where the rocks of the Aravalli
Supergroup occur, is divided into three contiguous sectors: i) the northeastern sector of Bhilwara region;
ii) the central sector of Udaipur region; and iii) the southern sector of Lunavada region. Each of these
three sectors is characterised by distinctive deformational and metamorphic features, in spite of the fact
that there is no distinct line of separation between these sectors. Out of these three sectors, the central
sector, which includes Udaipur region, between Nathdwara and Dungarpur, exposes the best sections
showing complete succession of the Aravalli Supergroup. As mentioned before, this is the region, which
is known as the ‘type area’ of the Aravalli Supergroup. The stratigraphic succession of the Aravalli
Supergroup is shown in table 3.
Lithology
In this section we propose to present a detailed description of different lithological units of the
Aravalli Supergroup of the type area. This will help not only in understanding the relationship of
different lithological units of the type area, but also in attempting correlation of rocks of the other
sectors. Detailed lithological study of rock successions will also help in inferring the depositional
environment of these Palaeoproterozoic rocks.
Shelf facies: 1.Lower Aravalli Group
1.A. Delwara Formation
Around Udaipur valley, the rocks of this formation occur mainly along two sub-parallel strips (Fig.4).
The easternmost strip, which extends from southeast of Nathdwara in the north to Banswara in the
southeast forms a narrow band between the Mewar gneiss Complex in the east and the Debari Formation
in the west.
The succession starts with ‘clean-washed’ quartzites (orthoquartzites), locally grading into
conglomerates. Arkosic arenites are rather rare, whose occurrence is primarily confined to region west
of Udaipur.
The quartzites are not everywhere in direct contact with the basement rocks. A thin veneer of
metavolcanic rocks locally intervenes between the two. The contact between the basement and cover
rocks is invariably marked by discontinuous, lenticular pockets of white-mica deposits, which have
been interpreted as metamorphosed palaeosols (Roy and

Table 3. Stratigraphic succession of the Aravalli Supergroup (after Roy et al.1988, 1993)
Shelf sequences Deep-water sequences
Serpentinites Jharol -- Mica-schist
Formation with thin
Beds of
quartzites.
Serpentinites
UPPER (intrusions)
ARAVALLI Lakhawali Phyllite
GROUP Kabita Dolomite
Debari Formation Quartzite-arkose-conglomerate
(=Dantalia Quartzite
of Sarara inlier belt)
~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~ ~~~~~~~~~~~~~~~~
Tidi Formation Slate, phyllite with thin bands of
dolomite& quartzite
MIDDLE Bowa Formation Quartzite & quartzose phyllite
=Machhla Magra
Formation,
ARAVALLI (Roy et al.1988)
Mochia Formation Dolomite and facies variants,
GROUP =Zawar Formation, including carbonaceous phyllite
(Roy et al. 1988) with Pb, Zn, Ag
Udaipur Formation
(= Kathalia Formation of Greywacke/phylliete,
Zawar, Straczeck and Conglomerate
Srikantan, 1967)
~~~~~~~~~ ~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~
Jhmarkotra Formation Dolomite, quartzite, carbon
(=Mandli Formation of phyllite, phyllite, thin local bands
LOWER Zawar, Straczeck and of stromatiloitic phosphorite,
Srikantan, 1967) copper and uranium deposits
ARVALLI (=Raialo marble of Iswal &
Rajsamand)
GROUP
Delwara Formation Metabasalt with thin bands of
dolomite/quartzite, veins of barite
~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~ ~~~~~~~~~~~~~~~~
MEWAR
GNEISS
COMPLEX,
GRANITES
Pre-Aravalli gneisses,
amphibolite, granitoids,
metasediments, and
granitoids

Fig.4. Geological map of the region around Udaipur, between Nathdwara and Sarara
(Modified after Heron, 1953, and Roy et al., 1988).

underlying zone in some sections appears greenish coloured due to the presence of chrome-mica. The
white mica deposits, at places, show a gradational contact with quartz rich rocks containing chloritoid,
tourmaline, biotite, and magnetite. Large criss-cross, rectangular pseudomorphs of andalusite occur in
rare instances in this zone. In some sections, a meta-arkose layer occurs in between the pure white- mica
deposits and the gneiss-granite of the basement sequence (Shekhawat, 1982).
Minerals constituting the white mica include a pure variety of sericite mica of 2M type, and
quartz. Kyanite and/or sillimanite occur in certain rocks. Other minerals, which occur in minor amount,
include biotite, tourmaline, topaz, rutile, and detrital grains of zircon. Textural evidence indicates
formation of sericite mica out of kyanite and sillimanite. Sericite mica in these rocks is seen to replace
kyanite along cleavage planes and fractures (Sreenivas, 1999). The degree of replacement of kyanite by
sericite mica is variable, depending on the factor of shearing deformation in therocks.
1.B. Jhamarkotra Formation
The passage from the basal Delwara Formation of quartzite-metavolcanic association to the
next higher dominantly carbonate succession appears gradational in nature. The dolomitic rocks have
developed extensively in the shelf region of the Udaipur sector. Outcrops of dolomitic rocks form high
castellated ridges, which virtually encircle the valley of Udaipur. The carbonate rocks are dominantly
dolomitic in composition showing rapid changes in facies to orthoquartzite, ferruginous dolomite,
manganese-bearing dolomite, carbonaceous phyllite (black shale facies) and phyllitic dolomite. It also
passes to argillaceous phyllite, which contains intercalations of dolomitic limestone. In addition, at
many places there is a persistent horizon of stromatolitic rock-phosphate within the dolomitic sequence.
2. Middle Aravalli Group
2.A. Udaipur Formation
A sequence of greywacke showing rhythmic alternations with phyllite (Pandya, 1965;
Poddar and Mathur,1965) overlies the carbonate rocks of the Jhamarkotra Formation with a
prominent unconformity. The stratigraphic relationship is abundantly clear in several sections
around Udaipur (Fig.5 & 6) and around Zawar Mines area (24022': 73040'). A characteristic
feature of thick beds of greywacke is the presence of graded bedding. It ranges in composition
from feldspathic to lithic types. Coarser varieties of greywacke are pebbly, whereas the finer
ones are siltstones. General grade of metamorphism being very poor, most of these rocks
have retained sedimentary structures and textures. Damle and Sharma (1970) described a
succession of dark-coloured laminated rocks from the Udaipur region, which they considered
as a constituent of the greywacke succession. Laminations in these rocks,

Fig.5 . Lithostratigraphic
column of the shelf facies
rocks of the Aravalli
Supergroup around Udaipur.
Fig . 6. Schematic, restored east - west section through Udaipur city
showing facies, environment and time relationship in epicontinental
and deep sea.
2. Machhla Magra Formation
At Udaipur, the greywacke-phyllite sequence passes on to a sequence of quartzose phyllite or
quartzite. The formation was described as the Machhla Magra Formation by Roy et al. (1988). Outcrops
of this unit form low ridges along the western periphery of the city, fringing the lakes. The passage bed
between the greywacke and the next higher horizon is a thin sequence of argillites showing a host of
depositional and soft-sedimentary structures. Lenticular, thin beds of conglomerate comprising rounded
and poorly sorted pebbles of quartzite, vein quartz, dolomite, greywacke and phyllite form the base of
the formation. This is overlain by thickly bedded orthoquartzite, which grades upward into massive,
locally cross-bedded quartzite. The uppermost unit is of siltstone (very poorly metamorphosed) and
silly mudstone-arranged in fining-upward cycles.
The outcrops of the formation form low ridges, which virtually form eastern and southeastern
abutment of the lakes of the Udaipur City.
4. Upper Aravalli Group
3.A. Debari Formation
The sequence starts with poorly sorted, polymictic conglomerate beds containing pebbles,
cobbles and boulders of grey, white and light green coloured quartzite, vein quartz (Shukla and Sharma,
1970). The larger clasts of other lithologies include granite and granitic gneiss, marble, amphibolite,
tourmaline-rich rock and mica schist (Sinha-Roy et al., 1993). According to Shukla and

Sharma (1970), the pebbles of quartzite and vein quartz are mostly elongated and rod-like, whereas
these tourmaline-rich rock and granitic are rounded. In zones of intense deformation, the pebbles of
quartz-feldspar granites and micaschists, due to their extensive stretching, generally appear as narrow
streaks plastered on the rock matrix.
There is a general decrease in clast-size in the upward (in stratigraphic sense) direction. The matrix is
composed either of arkosic quartzite or of schistose quartzite. Thin lenses of dolomitic limestone and
phyllite occur within the conglomerate horizon, particularly near the basal part. Wedges of boulder
beds occur irregularly along the length of the major outcrops .
3.B. Kabita Formation
The dolomite occurs north of the line joining Kabita and Lakhawali, nothwest of Udaipur.
The outcrop forms a triangular framework with the inner part occupied by the rocks of upper
phyllite sequence. The dolomite is cream-white in colour, fine-grained to coarsely crystalline,
and shows a few intercalations of argillaceous rocks. Although generally massive, this unit
shows well developed cross bedding. Under microscope, the dolomite comprises fine-grained
carbonate minerals, which in some cases are flattened parallel to the schistosity.
3.C. Lakhawali Phyllite
This is the youngest formation, which occupy central portion of the triangular outcrop
of Kabita dolomite (Fig.7). There is a marked difference in the lithological character of this
phyllite from base to the top of the unit. Near the basal part, the rock shows an alternation of
lighter meta-siltstone and darker phyllite. Upward the rock grades to argillite. The bedding is
remarkably well preserved in this phyllite. The individual beds range in thickness from a few
millimetres in the laminites to over 2 cm in more quartzose unit. Soft sedimentary deformation
structures, which include pinch-and-swell structures, convolute laminations and other slump
features, are seen in the siltstone layers enclosed in the more argillaceous layers. At places,
the siltstone unit appears as lenses floating in argillaceous matrix. There are numerous bands
of grey dolomite and a few bands of dark violet grey quartzite.

DAY-1 Location-1
Date- 20/09/19 Time- 5:50 PM
Location Name- Jalotra Village, Palanpur danta highway
GPS coordinates-
• Latitude- N24°15’38.0”
• Longitude- E72°25’58.0”
Geology Formation- Isolated hills
Rock Type- Granite
Structures- Igneous Intrusion
Geomorphology-
• Spheroidal weathering could be seen
• Formed by erosional contact
• Ancient part of subduction zone
Stratigraphy- Erinpura Granites
Photograph-
Remarks-
• From this area calc silicate start as Gneissic rock which is a part of Cambay Basin.

DAY-1 Location-2
Date- 20/09/2019 Time- 6:30 PM
Location name- Near hanuman temple, Mahesena-Visnagar-Ambaji Highway
GPS coordinates-
• Latitude- N24°5’40”
• Longitude- E72°44’59”
Geology formation- Bended Gneissic Complex
Rock type- Black coloured Amphibolite with pegmatite veins of white colour.
Geological Structure-
• Parasitic folds with Z type fold.
• Cleavages were found in igneous rocks parallel to axial plane.
• Minor joints also found.
• Boudinage was found between incompetent and competent layers.
Economic Importance- Some trace elements are found like gold and uranium.
Photographs-

Remarks- Huge structures of amphibolite are seen with bands of white colour granite or
pegmatite veins representing boudinages.

DAY-2 Location-3
Date- 21/09/19 Time- 10:30 AM
Location Name- Kui-Chitrasani Fault Zone, Kui Village
GPS coordinates-
Geology Formation- Delhi Supergroup
Lithology/Rock Type-
• Quartzite
• Fault Breccia consisted of angular fragments
Fault Trend- North East- South West
Structures-
• Fault zone
• Joints
• Slickenside
Photograph-

Remarks-
• Quartzite has gone under faulting where fault breccia occurred which consists of angular
fragments of past rock embedded in ferruginous matrix.
• Since the cata-clasite has undergone on the shallower part of the earth crust therefore
rock has underground brittle deformation.
• The rock will not show any orientation.

DAY-2 Location-4
Date- 21/09/19 Time- 12:00 PM
Location Name- Balaram, Balaram river
GPS coordinates-
Rock Type- Charnockite
Structures- Inliers – An older rock formation isolated among newer rocks.
Geomorphology-
• Outcrop of Charnockite exposed along a riverbed.
Photograph-

Remarks-
• Charnockite is found in form of patches, commonly found in PALLAVARAM, TN.
• Riverbed has exposed typical metamorphic rock name Charnockite also known as
hypersthene bearing granite.
• It is an important rock belonging to granulites faces that have experienced high
temperature and moderate pressure.
• Charnockite has been uplifted and exposed in the surrounding of low-grade
metamorphic rock therefore this rock marks inliers.
• Index minerals are hypersthene and ortho-pyroxene with minerals like feldspar,
orthoclase, quartz, plagioclase, granite with also few minor minerals like biotite.
• Charnockite is an anhydrous rock because of the uplifted retrogation metamorphism.
• These granulites are referred as windows to the lower crust.
• It shows no orientation.

DAY-2 Location-5
Date- 21/09/19 Time- 1:30 PM
Location Name- North of Dabhela
GPS coordinates-
• Latitude- N24°27’47.0”
Rock Type- Mylonite (Ultra Mylonite)
Structures- Shear structures including S and C fabrics.
One essential fabric is present where-
S stands for schistosity fabric and C stands for sheared fabric.
Photograph-
Remarks-
• This rock is a resultant of the process called mylonitization where parent rock goes
extensive churning occurred in deep earth crust.
• It consists recrystallized matrix in which matrix content is about 70% to 80%.
• Pink colour represents the presence of Orthoclase.
• It represents ductile deformation in which original rock was granitic rock.
• Dark coloured rocks are in melanocratic colour where light coloured rocks are in
leucocratic coloured with less clast content and more matrix content.

DAY-2 Location-6
Date- 21/09/19 Time- 2:00 PM
Location Name- Shikhandwas
GPS coordinates-
• Latitude- N24°16’26.6”
Rock Type- Calc Granulite
Structures-
• Cleavages parallel to the hinge
• Quartz veins were also present.
Geomorphology- Differential weathering was seen.
Photograph-
Remarks-
• It is rich in CaCO3 contains diopside, plagioclase feldspar, garnet, calcite, grossularite.
• The texture is granoblastic
• Commonly this rock indicates differential weathering that occurs at different rates as a
result causes differences in weathering and resulting in an uneven surface.

DAY-2 Location-7
Date- 21/09/19 Time- 3:35 PM
Location Name- Kanpura
GPS coordinates-
• Latitude- N24°17’4.9”
Rock Type- Gabbro-Norite, Basic granulite
Structures-
• Knots of pyroxene were found.
• Cryptic layering was present in which alternate layering of pyroxene and plagioclase
were present.
Photograph-
Remarks-
• The Protolith of this rock is a Basic/Mafic Igneous Rock.
• The mineral content of this rock are augite, hypersthene and plagioclase feldspar
• Also known as two pyroxene mafic granulite because of presence of augite and
hypersthene.
• Knots of pyroxene could be seen with cryptic layering was present in which alternate
layering of pyroxene and plagioclase were present.

DAY-2 Location-8
Date- 21/09/19 Time- 4:35 PM
Location Name- Kingora village
GPS coordinates-
Rock Type- Mylonite in which Gneiss was found in pockets.
Structures-
• Alternate layering of light and dark layers.
Photograph-

Remarks-
• Two prominent shear zones are found, one of them is known as Kangora shear zone.
• Light coloured layer is known as Leucosome and dark coloured layer is known as
Melanosome.
• Alternative layering of dark and light coloured layers were present in which ultra-
Mylonite was present in the form of pockets.
• When top to right shear direction is seen, it is considered as planar view while seen from
cross sectional view, geographic direction in which the direction of shear remain same is
needed to be defined.

DAY-2 Location-9
Date- 21/09/19 Time- 5:15 PM
Location Name- 3 km ahead in east of Kingora village
GPS coordinates-
• Latitude- N24°17’47.9” Longitude- E72°41.5’11.3”
Rock Type- Pink granite (K-rich)
Structures-
• Batholiths, Porphyritic structure
Geomorphology- TOR weathering was encountered.
Stratigraphy- Sindhra ambaji granite
Photograph-
Remarks-
• Typical weathering known as TOR weathering was encountered.
• The age of Sindhra ambaji granite is recorded about 750 mya.
• This granite holds intrusive relationship with igneous rock. The rock type is potash rich
granite in which orthoclase is more than plagioclase due to which rock appears pink in
colour. As per the tabular classification of igneous rock, this granite is porphyritic
structure happened due to magmatic disturbance difference in depth of crystallized
rock. The granites are of syn-orogenic granite (s-type).

DAY-3 Location-10
Date- 22/09/19 Time- 10:30 AM
Location Name- Near Mandali village
GPS coordinates-
• Latitude- N24°12’25” Longitude- E72°57’53.0”
Geology Formation- Kumbhalgarh group
Rock Type- Calc gneiss
Dip-Strike-
o Dip Amount- 85°
o Dip Direction- North 110°
o Strike- NE-SW
Structures-
• Rib and Furrow structure
• Folds
• Lineation
• Boundinage (Chocolate boundinage)
Geomorphology-
Elephant skin weathering was seen.
Economic Importance-
Calc gneiss is used in cement industry.
Photographs-

Remarks-
• Gneiss belongs to Kumbhalgarh group of Delhi supergroup which is extended in Gujarat
as well
• Kumbhalgarh group is the most dominant group in south delhi supergroup whereas
Alwar is the dominant group in north delhi supergroup.
• Kumbhalgarh rock composition consists of two types of rocks i.e. Argillaceous and
Calcareous.
• Intermediately this group is intruded by syn sedimentary volcanic activity where
different form of dykes and sills are found. Example- Dolerite and Basalt
• The whole package has gone under deformation and metamorphism (deformation and
metamorphism are synchronous).
• Argillaceous will change to phyllites whereas calcareous will change into marble
• This rock belongs to Amphibolite facies grain size, varying from fine to medium grain.
• The mineral contents are calcite, dioxide, plagioclase, feldspar, microcline, spine and
quartz. Dioxide is the characteristic mineral for calc gneiss.
• The lines which were visible is known as gneissic structure and under microscope it
shows granoblastic texture which under deformation had gone vertical.
• It has gone weather under atmosphere where the less hardened mineral will weather
fast like calcite as compared to more hardened mineral like quartz. This is also known as
differential weathering.
• Structures like crest and trough of a wave were seen which are known as rib and furrow
structure. Because of this, pseudo gneissic structure was seen.
• Chocolate type boudinage and veins of granite were seen.

DAY-3 Location-11
Date- 22/09/19 Time- 12:07 PM
Location Name- Manik Nath Caves
GPS coordinates-
Rock Type- Granite (Plagio-granite)
Structures-
• Caves
• Xenoliths
• Stocks
Geomorphology- Caves were found.
Photograph-

Remarks-
• Colour of plagio-granite is grey which dominantly consists of plagioclase and less
amount of Orthoclase.
• Caves were seen which is the example of TOR weathering which includes both physical
and chemical weathering.
• The rectangular crystals were plagioclase feldspar.
• We need to pick axis to decide the granite is deformed or not. Likewise, if the
orientation is not seen then technique called Anisotropy of magnetic study is used.
• There were xenoliths within the granites where composition of xenoliths is granodiorite.
• The age of inner xenoliths was older than outer xenolith which indicates post orogenic
nature in which replacement takes place after orogeny.
• Xenolith is one of the examples of magmatic assimilation and magmatic contamination.

DAY-3 Location-12
Date- 22/09/19 Time- 4:00 PM
Location Name- Nani Tundadiya
GPS coordinates-
Geology Formation- Kumbalgarh group of delhi supergroup
Rock Type- Meta-gabbro
Structures-
• Joints
• Cryptic layering
• Relict texture
Photograph-

Remarks-
• Highly jointed, unifoliate and massive Meta-gabbro was found.
• Texture of meta gabbro was medium to coarse grain.
• Mineral composition consists of Augite, olivine and plagioclase.
• Quartz veins were intruded inside.
• Cryptic layering or alternate layering between augite and plagioclase were seen.
• Protolith of this rock is Igneous rock gabbro which had gone metamorphosed.
• Granoblastic texture was found between the grains.
• Process is involved here in which plagioclase gets converted into epidote by the process
of regional metamorphism.

DAY-3 Location-13
Date- 22/09/19 Time- 4:35 PM
Location Name- Dadadu, Shree Balaji Hanuman temple, Danta
GPS coordinates-
Geology Formation- Kumbalgarh group
Rock Type- Gneissic rock
Structures-
• Augen structure
• (Phi) type porphyroclastic structure
Photograph-

Remarks-
• Gneissic structures were seen.
• Dark bands on the rock were of Biotite whereas light bands were of K-feldspar and
plagioclase.
• Phi (φ) porphyroclastic structure was seen where structure looks like the Greek letter
(φ) as shown below.
• Augen structures were also present in which in some gneissic metamorphic rocks, a
structure consisting of minerals like feldspar or quartz that have been squeezed into
elliptical or lens-shaped resembling eyes (augen).
• Here argillaceous rock composition undergone regional metamorphism.

DAY-3 Location-14
Date- 22/09/19 Time- 4:45 PM
Location Name- Nawabas, Danta highway near Kanabiya vas
GPS coordinates-
Rock Type- Aplite (fine grain variety of granite)
Structures-
• Fracture in country rocks.
• Antiformal syncline fold.
Photograph-
Remarks-
• Pink colored Aplite named rock which is a fine-grained variety of granite found.
• Formation of Aplite takes place due to the formation of dyke in core of folding where
the trend of folding was East-West
• There were few numbers of fractures found in country rock.
• It acts as a sealing agent because it accommodates all the fracture.
• Structurally antiformal syncline fold was present in which left and right hills were
dipping in opposite direction.

DAY-3 Location-15
Date- 22/09/19 Time- 5:35 PM
Location Name- Pipalavali Vav, Near Trishulia Mata Temple.
GPS coordinates-
Rock Type- Gneiss
Structures- Folds including Recumbent fold.
Photograph-

Remarks-
• Mechanism of folding-
o Bending- Bending is the process in which the layer gets perpendicularly
compressed.
o Buckling- Buckling is the process in which compressional stress gets acted
parallel.
o Passing Folding- Shear induced folding is included in passive folding.

DAY-4 Location-16
Date- 23/09/19 Time- 09:45PM
Location Name- VK Trivedi Marble Mines
GPS coordinates-
Rock Type- Marble (Metamorphic)
Dip-Strike-
• Dip Amount- 70°
• Strike direction- NW-SE
Structures- Igneous intrusion like dykes
Photograph-

Remarks-
• Marble is a metamorphic rock of composition CaCO3 which is a result of contact and
regional metamorphism.
• It is a oldest mechanized mine conducted by machinery system started in 1948.
• Marble can be found in 100 mts of depth.
• Production of 300 ton is done each day or 8000 ton/month.
• Around 3-5 mts depth we get clay, at 10-15 mts we get epidiorite rock and at 15-20 mts
we get marble.
• Impurities are also present like igneous intrusion including dykes.
• 75+ whiteness marble is considered as A grade marble similarly 50-75 whiteness marble
is considered as B grade and below 50 whiteness marble is considered as C grade.
• Mining closure plan is to be made for closing the mine.
• Methods like compressed air drilling, diamond drilling, bore hole survey, mapping and
reference pit are used.
• Greenish rock is also found named Epidote.
• Vertical drilling, horizontal drilling and diamond cutting is used for perfect cutting of
marble.

DAY-4 Location-17
Date- 23/09/19 Time- 12:00 PM
Location Name- Soorpagla, Abu-ambaji road
GPS coordinates-
Geology Formation- Soorpagla pelitic granulite
Rock Type- Pelitic Granulite
Structures- Mafic dyke in country rock
Photograph-

Remarks-
• Alternate bands of light and dark colored were found.
• Mineral composition consists of quartz, K-feldspar, mica and garnet
• Metamorphism of argillaceous rock happened.
• Mafic dyke in country rock was found that is granulite.
• Also, some pegmatite intrusion or veins were found along with dolerite dyke.
• Trend of dyke was found NE-SW.

DAY-5 Location-18
Date- 24/09/2019 Time- 1:45 PM
Location Name- Tulsidas ji ki sarai village, near dewari
GPS coordinates-
• Latitude- N°36’45.3”
Geology Formation- BGC and Aravalli supergroup
Rock Type-
• Bended Gneissic Complex
• Quartzite
• Pyrophyllite
Dip-Strike of the rock-
• Dip direction- East-70°
• Strike- NW-SE 330°
Structures- Paleosol unconformity is present between the BGC and Aravalli.
Photograph-

Remarks-
• When feldspar gets weathered, it covers into clay and when it gets metamorphosed it
changes into pyrophyllite rock which is a low-grade metamorphic rock. Pyrophyllite is a
green coloured rock.
• Quartzite was found in vertical orientation.
• The Archean-Proterozoic boundary was marked by BGC (Bended Gneissic Complex).
• Pyrophyllite indicates the Paleo-Proterozoic and Aravalli boundary.

DAY-5 Location-19
Date- 24/09/19 Time- 3:15 PM
Location Name- Near debari, opposite of circuit house
GPS coordinates-
Geology Formation- Aravalli formation
Rock Type- Conglomerate
Photograph-
Remarks-
• Same type of polymictic conglomerate are found in Delwana.
• These are deposited in the graben due to the steep slope of fault plane.
• In this conglomerate, the pebbles are not rounded but they are elongated due to the
stress.

DAY-5 Location-20
Date- 24/09/19 Time- 4:10 PM
Location Name- NH-27, near chunda mahila college
GPS coordinates-
• Latitude- N24°39’16” Longitude- E73°44’04”
Geology Formation- Jhamarkotra formation
Rock Type- Carbonaceous shale
Photograph-
Remarks-
• It was a road cutting section.
• Syn rift volcanism happened during rifting.
• Delwara meta volcanics is overlain by Carbonaceous shell.
• Green color patches of Sulphur are present in which odour of Sulphur could be felt.
• Pyrite was also present in purple color.
• It indicates low grade metamorphism.
• After volcanism, the vegetation occurs and due to continuous deposition, it gets
converted in Carbonaceous shale.

DAY-6 Location-21
Spot-A
Date- 25/09/19 Time- 09:45 PM
Location Name- Jamuniya ki naal
GPS coordinates-
Geology Formation- Older mewar gneiss.
Rock Type- Ahar river granitic gneiss.
Structures-
• Cleavages
• Quartz veins intruded.
Geomorphology-
Stratigraphy- Mewar gneiss complex
Photograph-

Remarks-
• Aravalli has different granitoid basement.
Mewar Gneissic complex lithology can be divided into 4 types-
• Untala
• Gingla
• Ahar river
• Berach
• Two large bodies of granite within the MGC are the Untala granite and the Gingla
granite. The major bodies of granite ‘inliers’ are the Berach granite near Chittaurgarh
and the Ahar River granite near Udaipur.
• A characteristic feature of all this granitic gneiss is the coarse-grained porphyritic
texture
• On top basaltic quartzite is found.
• We were standing on upper Archean rock overlayed by Paleosol.
• Stratigraphy section can be divided into two types:
• Type section- Complete succession is found at one place.
• Reference section- Only marker bed age is known.
• Low grade metamorphism occurred.
• Basement is covered by Sarara inlier belt.
• Trend – NE -SW is being found which is similar like delhi supergroup and sirohi.

Spot B
Time- 10:40 AM
Rock type- Chlorite Schist
Structures-
• Crenulation cleavages were found and micro folds were found (small folds in big fold)
• Quartz veins are intruded in granite.
• Boudins and Mullions were also present.
• Lineations were found.
Photograph-
Fig. 1 Fig. 2

Fig. 3 Fig. 4
Remarks-
• We can see S0, S1 and S2 structures.
o S0 refers to bedding plane.
o S1 refers to cleavages.
o S2 refers to secondary cleavages.
• Antiformal syncline fold formed in which S0 is parallel to S1 (S0 II S1).
• In second phase folding S0 ll S1 and S1 is perpendicular to S2 (Fig 3).
• Mullions (Boudins) were found (Fig. 2).
• Crenulation cleavages were found indicating two or more stress directions causing the
formation of the superimposed foliations.
• Lineation were also present (Fig. 4).

DAY-6 Location-22
Date- 25/09/19 Time- 12:37 PM
Location Name- Near Iswal village, Near Iswal highway
GPS coordinates-
• Latitude- N 24°43’5.2” Longitude- E 73°37’58”
Rock Type- Clay (Meta–sedimentary rock)
Dip-Strike of the rock-
o Dip direction- North-270° Dip Amount- 79° Strike- NW-SE
Structures-
• Bedding plane of clay beds found.
• Cleavages perpendicular to bedding plane found.
• Tight folds are also present.
Photograph-
Remarks-
• Clay (meta-sedimentary) beds were nearly vertical forming folding structures.
• Tight folds could be seen in which limbs are parallel to axial plane.
• Cleavages could be seen making 90° angle with bedding plane at limbs of the folds
whereas parallel to bedding plane at hinge of the fold.

DAY-6 Location-23
Spot-A
Date- 25/09/19 Time- 1:30 PM
Location Name- Dharmeshwar mahadev temple, south of Gogunda village
GPS coordinates-
• Latitude- N 24°44’14.3” Longitude- E 73°33’18.5”
Rock Type- Mica Schist
Structures- Folding structures like micro folds including Z, S and M folds, Isoclinal folds and
plunging folds were found.
Photograph-

Remarks-
• Micro folds like Z fold, M fold and also isoclinal fold were found.
o Z folds indicates the left limb of a fold.
o S folds indicates the right limb of a fold.
o M or W folds indicates the hinge or middle part of a fold.

Spot-B
Time- 2:50 PM
GPS coordinates-
• Latitude- N24°44’5” Longitude- E73°33’18”
Geology Formation- Kaliguman extension.
Rock Type- Ultramafic rock (Silica content is less than 45%)
Structures-
• Asbestos veins intruded.
• Fractures were found.
Stratigraphy- Kaliguman Rikhabhdev lineament
Photograph-
Remarks-
• Kaliguman extension (rocks are ultramafic in Kaliguman) in which fibrous Asbestos vein
intruded in it.
• Talc in the form of Schist found which was scratchable because of low hardness.
• Mineral composition consists of talc, magnesite (carbonate of magnesium) and
serpentine.

DAY-7 Location-24
Date- 26/09/19 Time- 9:45 PM
Location Name- 45 km North-East of Udaipur, Newania village
GPS coordinates-
• Latitude- N 24°39’1.7”
• Longitude- E 74°3’36.4”
Geology Formation- Newania Carbonatite
Rock Type- Carbonatite
Structures- Apatite veins intruded
Photograph-

Remarks-
• Carbonatites found in the form of intrusive and extrusive bodies.
• Carbonatite is rich in rarer element that is why they are important.
• It occurs scattered body in the form of cracks.
• There are 527 occurrence of Carbonatite all over the world in which India has 20
major and 11 minor Carbonatite occurrences.
• Rajasthan state has 4 major Carbonatite occurrences:
o Sarnu Dandali Kamathi Carbonatite
o Mundwara Carbonatite
o Newania Carbonatite
o Bhamni Carbonatite
• Newania Complex relates to the Aravalli orogeny (Proterozoic), while the remaining
three: Mundwara, Sarnu-Dandali-Kamathi, and Bhamni, represent the pre-Deccan
Flood Basalt carbonatite-alkali activity.
• Newania Carbonatite intruded old Untala granite in BGC 2.95 billion years ago.
• Newania carbonatite is exposed 3km in length whereas 500m in width.
• Carbonatite can be classified into 4 types:
o Calciocarbonatite
o Magnesiocarbonatite (Dolomitic)
o Ferro carbonatite (Iron rich)
o Natrocarbonatite

• Mineral composition consists of apatite, magnetite, siderite, graphite, sodalite,
pyrochlore, dolomite and ankerite.
• Carbonatite contains total 17 REE (Rare earth elements) and 2 transition elements.
o REE concentration is counted when concentration is between 54 ppm-2479
ppm.
• Carbonatite originated in earlier and late phase in which earlier phase consists of
magnesia rich intrusion and late phase consists of ferro rich intrusion.
• Carbonatite originated from mantle concluded by the concentration of Strontium
(found in mantle) and ND.
• CBS (Chlorite biotite schist) can be seen in carbonatite.

DAY-7 Location-25
Date- 26/09/19 Time- 11:20 AM
Location Name- Rundera village
GPS coordinates-
• Latitude- N24°38’30.9”
Geology Formation- Extension of Newania Carbonatite.
Rock Type- Magnesio-carbonatite
Photograph-
Remarks-
• Course grained, magnesio-carbonatite found containing large crystal of magnesium.
(dolomitic carbonatite).
• Composition contained less REE (Rare earth elements).
• This Carbonatite is radioactive in nature therefore harmful for health.
• Illegal mining is done by locals used in construction/building material.

DAY-7 Location-26
Date- 26/09/19 Time- 3:35 PM
Location Name- Bhojunda Stromatolites park, Chittorgarh-Udaipur state highway
GPS coordinates-
• Latitude- N24°50’32.6” Longitude- E74°35’12.3”
Geology Formation & Rock Type- Bhagwanpura limestone
Geological Age- Proterozoic age
Structure- Apatite veins intruded.
Stratigraphy- Vindhyan formation
Photograph-
Remarks-
• In 1976, this was declared as world heritage park.
• Stromatolites are structures produced by blue-green algae. They are stratiform,
columnar and nodular structures in carbonate rocks resulting from the combination of
life activity and sediment trapping. They form generally in shallow water.
• They gave the way to eukaryotic life by giving oxygen which reacted with iron formed
Bended Iron Formation (BIF).
• It was found in Bhagwanpura limestone in convoluted shape.

DAY-7 Location-27
Date- 26/09/19 Time- 04:25 PM
Location Name- Great Boundary Fault, Bodiyana, Chittorgarh
GPS coordinates-
Geology Formation- Nimbahera shale
Rock Type-
• Shale and exposure of granites at some places
Dip-Strike of Rock-
• Dip Direction- 233° NW-SE
• Strike- 143° NE-SW
Structures-
• Folds like chevron folds (sharp hinges) found.
• Joints were seen across the folds.
Geomorphology- Berach river was flowing in lineament.
Stratigraphy-
• Nimbahera shale belongs to lower vindhyan supergroup.
• Great boundary fault separates two major domain Aravalli craton (BGC) and Vindhyan.
Photograph-

Remarks-
• Tetro-stratigraphic boundary – Great Boundary Fault separates two major domain
Aravalli craton and Vindhyan supergroup.
• Nimbahera shale was exposed of lower Vindhyan supergroup.
• Great boundary fault is highly sheared which displaces boundary.
• Exposures of granite found at some places.
• It was last activated in Quaternary.
• Several folds can be found like chevron folds (sharp hinges).
• Berach river was flowing across the lineament.
• Trend of fold was NE-SW

DAY-7 Location-28
Date- 26/09/19 Time- 5:10 PM
Location Name- Padmavati palace, Chittorgarh fort
GPS coordinates-
• Latitude- N24°52’58.6”
Geology Formation- Kaimur Sandstone
Rock Type- Feldspathic sandstone
Geological age- Proterozoic sedimentary structure
Structures-
• Current bedding was seen.
• Ripple marks structure encountered.
• Several small faults were also seen.
Stratigraphy- Vindhyan supergroup
Photograph-

Remarks-
• It is a part of upper Vindhyan which is not subjected to orogenic activity.
• Vindhyan are known for its uniform distribution of sandstone.
• The whole rock moderately sloping which may indicate a fault.
• The bed shows good asymmetrical ripple marks which were carbon rich.
• The sandstone beds were uniform and fine grained.
• No metamorphic activities took place because they were in a salted block.
• Most Mughal monuments as well as Indian Parliament are made up of Vindhyan
sandstone.

DAY- 8 Location-29
Date- 27/09/19 Time- 10:25 AM
Location Name- Jhamar Kotra phosphate mine
GPS coordinates-
• Latitude- N24°28’5.4”
Geology Formation- Jhamar Kotra formation
Rock Type- Dolomite (host rock)
Structures-
• Normal faults were found.
• Apatite veins intruded.
Geomorphology- The ore body is shaped like horseshoe.
Stratigraphy- Aravalli supergroup
Photograph-

Remarks -
• It was started in year 1968.
• Chemical formula of phosphate- Ca5Y(PO4)3.
• Phosphate ore is classified into two types based on quality-
o High grade ore - 30% or more P2O5
o Medium grade ore – 12% to 25% P2O5 in which processing is needed.
• Average bench height is 10m and average thickness is 10m
• Production of about 3000 ton each day is done in which 1 kg explosive is needed to
extract 6 kg phosphate.
• Depth of Jhamar Kotra mine is 210m and total area is speeded over 13 km.
• GSMC baroda is major buyers.
• Phosphate form igneous, sedimentary and metamorphic rocks got eroded out and
accumulated in the basin where it was eaten by algae which formed Stromatolites.
• Due to high temperature and pressure dolomitic matrix gets leached out.
• Considering ore body as fault plane, we need to remove hanging wall above it by
blasting method to get the ore body that is phosphate.
• Under depth with increased temperature and pressure results in melting of rock
phosphate which further result in arrival of it from weak zones like cracks and fractures.
• This phosphate belongs to Jhamar Kotra formation under Aravalli supergroup.
• Cutoff grade- less than 25% P2O5 considered as low grade whereas more than 25%
P2O5 considered as high grade.
• Grade increases with folding whereas when we approach hanging wall to footwall the
grading decreases.
• Black and white colour bands were found in which black bands were of Dolomite
(matrix) and white colour part was of phosphate.
• After removing the fine grain matrix, it becomes the ore changes into high grade.

DAY- 9 Location- 30
Date- 28/09/19 Time- 8:45 AM
Location Name- Haldighati, near Maharana Pratap museum
GPS coordinates-
• Latitude- N24°53'41.3" Longitude- E73°42'19.7"
Geological age: Paleo-Proterozoic
Rock Type-
• Laterite (weathering sequence of Basalt)
• Quartzite
• Mafic rock
Structures- Wavy and altered structure.
Stratigraphy- South Delhi fold belt
Photograph-
Remarks -
• Laterite is a soil type rock rich in iron and alumina formed in hot and wet tropical areas.
• Laterites found in reddish colour due of high iron oxide (FeO2) content but in Haldighati
laterite was found in yellow colour.
• Weathered sequence of basalt effected by alterations and gradations
• Sheared bed of quartzite was found.
• Peridotite was also present.
• Calcareous rocks converted into calc gneiss which has gone under metamorphism.

DAY-10 Location-31
Date- 29/09/19 Time- 11:45 AM
Location Name- NH-27 (road cutting section)
GPS coordinates-
Rock Type- Meta sedimentary rocks
• Quartzite
• Biotite schist
Structures-
• Dendritic
• Joints present
• Z and S type folds were found.
• Boudinage present
• 2 set of cleavage
• Phacolith
• Granitic intrusion (Pegmatite and Aplite)
Stratigraphy- Delhi supergroup, Aravalli
Photograph-

Remarks-
• Sandstone and shale intercalated beds were present due to metamorphism got
converted into Quartzite and Biotite schist.
• Later quartzite got intruded by granite and got metamorphosed again. Due to high
pressure, boudinage of granite were formed in quartzite.
• At some place granite vein is thin while at some places it is thick showing phacolith
bodies.

DAY-10 Location-32
Date- 29/09/19 Time- 5:00 PM
Location Name- Mount Abu road (Road cutting section)
GPS coordinates-
Geology Formation- Aravalli fold mountain
Rock Type- Meta sedimentary granitic gneiss
Structures- Large batholith
Geomorphology- TOR weathering
Photographs-
Remarks-
• Meta sedimentary granitic gneiss occurred in road cutting section.
• Porphyritic to non-porphyritic biotite granite in which medium to coarse grain texture
was found.
• Mineral composition consists of mica, feldspar and quartz.
• It is a batholith means a big body of granite made up of magma which cooled deep in
the subsurface. This magmatic episode is a part of malani igneous suite.

Geological Fieldwork File

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