2. Aravalli Craton is divided into eight tectono-
stratigraphic elements:-
Archaean Mewar Gneiss with Ancient
Supracrustal Enclaves
Bhilwara Supergroup ( Hindoli Group, Mngalwar
Complex and Sandmata Complex)
Mineralised Supracrustal Belts ( Rajpura-
Dariba, pur-Banera)
Palaeoproterozoic Aravalli Fold Belt
Mesoproterozoic Delhi Fold Belt
Neoproterozoic Basins
Neoproterozoic Malani Igneous Suite
Neoproterozoic Malwar Basins
3. Aravalli craton is unique, it does not
contain typical greenstone belts.
The craton is composed of quartzites,
marbles, pelites, greywackes.
The orogen consists of two prominent fold
belts of Aravalli and Delhi.
The Archaean basement of grey gneisses
known as the Banded Gneissic Complex
(BGC).
4. Aravalli craton is also distinguished by the
occurrence of the largest felsic volcanic
province of India ( Malani Igneous Suite).
The cratin haslarge Pb-Zn-Cu deposit of
India, besides containing stromatolitic
phoshorites and famous decorative
marbles.
5.
6. Great Boundary Fault bounding the Vindhyan
basin to the east and Hindoli belt to the west.
Banas Linement seperates Hindoli from
Manglwar Complex in the north and Mewar
Gneiss in the south.
Delwara Lineament marks a gradational
metamorphic-migmatic or sheared tectonic
contact between Manglwar and Sandmata
Complexs.
7. Kaliguman Linement that seperates Delhi fold
belt from Sandmata Complex in the north and
Aravalli fold belt in the south.
Rikhabdev Lineament enclosing an
ultramafic-mafic belt between shallow shelf
and deep-water facies in Aravalli fold belt.
Phuland Lineament marked by ultramafic-
mafic belt in the west of Delhi fold belt.
8. • Enclaves of superacrustal rocks like
amphibolites, quartzite, mica, schist,
crystalline limestone, cal-silicate rock and
banded iron formation are widely scattered
within the Mewar Gneiss.
9. The grey gneisses, migmatites and granitoids
of the Mewar region called as Banded
Gneissic complex (BGC).
Mewar Gneiss forms an incontrovertible
basement to Aravalli Supergroup and
corresponds to the migmatites and gneisses
of Mangalwar Complex.
10. The Archean granites and gneisses of the
craton have evolved into two stages.
The first stage is the generation of
amphibolites from peridotitc mantle.
The second stage is the partial melting of
amphibolites to produce TTG gneisses and
younger granitoids.
Geochronological data shows earliest
orogenic cycle in the craton of period from
3300-2900Ma.
11. Banded Gneissic Complex (BGC) included a
series of gneisses and granulites.
Hindoli Group: consisting turbidites and
minor volcanics.
Hindoli Group consists of greywackes and
phllites, besides minor cross-bedded
quartzite, dolomitic limestone and dolomite,
tholeiitic basalts, basaltic andesites, dacites
and rhyodacites.
Patches of dolerite and amphibolites.
12.
13. Mangalwar Complex gneisses occurring
between the Banas Lineament and the
delwara Lineament.
Sandmata Complex consists of large areas of
magmatic gneisses in amphibolites facies
containing enclaves. Granitoids of masuda
and Badnor areas have dates around 2830Ma.
14.
15. Many subparallel belts of arenite-carbonate
association with black shales and BIF, hosting
important lead-zinc mineralisation in the
craton.
The age of these belts is reckoned as
Palaeoproterozoic (~ 1800Ma).
It include:-
Jahazpur Belt- ~2600 Ma
Sawar Belt- ~2030 Ma
Rajpura-Dariba Belt- ~2350 to1800 Ma
Pur-Banera Belt
16. Palaeoproterozoic Aravalli fold belt (2200-
1800).
Consists of phosphatic stromatolites,
dolomites, in preference to calcic limestones,
carbon and prominent lead-zinc.
17.
18. Champaner Group
Lunavada Group
Jharol Group
Aravalli Udaipur Group
Supergroup Debari Group
Delwara Group
----Unconformity----
Sandmata Complex
Mangalwar/ Sandmata complex
Mewar Gneiss withenclaves of Jagat Group
19.
20. The Mesoproterozoic Delhi fold belt is a
linear belt.
Two principal divisions of North Delhi Fold
Belt (NDFB) and South Delhi Fold Belt (SDFB).
The dividing line separating them is called
Bithur-Pisangan Line.
21. North Delhi Fold Belt includes the Khetri
basin.
NDFB contains loosey contiguous basins
separated by faults
(i) Bayana-Lalsot basin, and
(ii) Alwar basin.
South Delhi Fold Belt is divided into two
The eastern Bhim basin, and
The western Sendra basin, separated by the
median Beawar gneiss.
22. Malani Igneous Suite (MIS) forms the largest
felsic volcanic province.
Represent major event of anorogenic, within-
plate magmatism in the Neoproterozoic
(680-780 Ma) of Marwar craton.
Volcanicas with a very large felsic component,
ring intrusions, and radial dykes.
Volcanics are mainly rhyolite, perlite and
trachyte.
Dykes like felsite and porphyry form the final
phase of Malani magmatism.
23.
24. Three phases of igneous activity based on
field relations, mode and type of magmatism
as well as texture and compositon of rock
types:
3. Dyke swarms : Gabbro, dolerite, granite,
aplite, rhyolite, andesite, trachyte.
2. Granitoids: Malani, Jalor and Siwana
granites
1. Bimodel volcanics: Rhyolite, rhyodacite,
dacite and trachye, basalt and trachy-
andesite.
25. The earliest geological event in the craton in
the generation of TTG gneisses at ~3300Ma
from LREE depleted mantle.
Two stage melting and fractionation into
tholeiites and tonalites.
Intrusionof granitoids and mafic dykes
completethe first cratonisation event at
~2800 Ma.
26. The next major crationisation event occurred
at ~2500-2600 Mawhen berach Granite and
associate GAG gneisses were formed by
melting and mixing of juvinile and crustal
components.
Large suites of paragneisses, quartzites,
marbles, calc-silicate rocks and amphibolites
belonging to Bhilwara Group, occur as
enclaves in the Manglawar Complex.
