General
Information
| Area |
: |
5,49,000
sq km |
| States |
: |
Rajasthan,
Gujarat and parts of Madhya Pradesh |
| Headquarter |
: |
Jaipur |
| Address |
: |
Regional
Centre for Exploration and Research,
AMD Complex, Sector-5 Extension, Pratap Nagar, Sanganer,
Jaipur - 303906
|
| Contact
Person |
: |
Shri
L. K. Nanda, Regional Director
Ph
: 0141-2793598
Fax
: 0141-2791126
e-mail
: rdwr.amd@gov.in
|
The
Region was set up initially as North Western Region during
1988 when it was carved out of Northern Region.
It was housed in rented accommodations till recently and in
2004 a new office-laboratory building has been completed.
The Region has residential quarters catering to the requirements
of officers
and staff.
Broad
Geological features
The
following are the broad geological domains of the Western Region.
(i)
Archaean Basement Rocks ( >2500 Ma) :
The
Banded Gneissic Complex (BGC) with enclaves of amphibolites and
intrusive granitoids such as Untala granite, Gingla granite,
Berach granite etc. which form the basement for Aravalli and
other younger meta-sediments.
(ii)
Lower Proterozoic Aravalli Supergroup rocks:
The
Aravalli Supergroup of rocks, which were deposited in rift related
basins, form the most prominent geological feature. The Aravallis
consist of basalts, quartzites, carbon phyllites, marbles, greywackes,
conglomerates, arkoses etc. These rocks are well known for their
intricate folding and multiple deformations. Some synkinematic
granitic bodies e.g. Darwal granite, Amet granite is emplaced
into it.
(iii)
Middle to Upper Proterozoic Delhi Supergroup rocks and their
equivalents:
The
succeeding Delhi Fold Belt comprises limestones, quartzite, arkose,
quartz- mica schists and contemporaneous volcanic rocks. They
were deposited mostly in the northeastern part of Rajasthan.
They are also intricately folded with several granitic emplacements.
The
Champaner Group of rocks were deposited along the southern fringe
of Aravallis during upper Proterozoic period. Godhra granite
was emplaced into them synkinematically.
(iv)
Neo Proterozoic rocks of Western Rajasthan:
A
number of younger (800 m.y.) intrusive/ extrusive bodies such
as Malani, Angor, Siwana, Jalore occur in the western part of
Rajasthan. Over them are deposited Marwar Supergroup of rocks
comprising mica schists, phyllites and quartzites.
Besides,
Deccan Trap of Mesozoic age and Vindhyan rocks of Upper Proterozoic
age occupy small parts of the Region.
Summary
of Investigations :Important finds
A
major part of radiometric surveys were directed to locate
vein and other deposits in Proterozoic basins. Some of the
uranium deposits identified during
the
period are :
Umra-Udaisagar-Kalamagra
tract: It
is located in Udaipur district, Rajasthan. The host rocks
are carbonaceous phyllites and dolomites of Aravalli Supergroup.
This deposit is divided in Umra main and Umra north-east.
It is a vein type of deposit occurring over 650m strike
length in Umra main and 750m in Umra north-east and within
a vertical depth of 315m and 400m respectively. This
area is being re-investigated from the standpoint of unconformity
type of uranium mineralisation.
Rohil: It is located in Sikar district, Rajasthan and lies along
the albitite line, a 
300 km NNE-SSW trending
zone of extensive albitisation. The host rocks are
albitised biotite schists of the Delhi fold belt. It is albitite
type of deposit occurring over 1850m strike length and within
a vertical depth of 500m. Exploration is in progress here.
QPC
Occurrences: Radioactivity associated with Quartz Pebble conglomerates
(QPC) overlying Banded Gneissic Complex (BGC) has been
located at Kharbar in Udaipur district, Rajasthan. This
occurrence has now been taken up for detailed studies.
In
addition,
a number of columbite-tantalite, beryl, lepidolite-bearing
pegmatite occurrences are located along Rajasthan mica
belt at Deoria, Sangwa, Lakhola, Soniana and Danta-Bhunas. 
Present
Thrust areas of Investigations
The
present thrust of uranium exploration is mainly in the following
three geological environments
(a) Albitite Line: Along
the Albitite line, which coincides with the major fold axis of
Delhi fold belt, radiometric survey and exploration are being
carried out to discover more occurrences similar to
Rohil.
(b)
Jahajpur basin: Survey
and exploration are also concentrated in the Lower Proterozoic
rocks of Jahajpur basin overlying the Hindolis of BGC in Bhilwara
district of Rajasthan. High grade uranium mineralisation, along
with traces of gold and silver, was recently discovered associated
with banded calc arenaceous unit of the Jahajpur basin.
(c) The unconformity contact of
the Neo Proterozoic Marwar Supergroup rocks and the Lower Proterozoic
Aravalli - Delhi metasediments is considered as a potential horizon
for uranium mineralisation. Programme has also been drawn up
to look for unconformity related uranium mineralisation in this
set up.
(d) Quartz
Pebble Conglomerate: Radioactivity in Lower
Aravalli QPC is known since 1960 though majority of samples
were thoriferous. Radioactivity due to uranium was located
in Lower Aravalli QPC during 1974-75 at Parsad. Later radioactivity
was also recorded in migmatites and biotite schist in basement
below the conglomerates near Kharbar. Thus, the area around
Sarara inlier has potential for locating QPC type uranium
mineralization in the Aravalli metasediments and also epigenetic
mineralization along faults traversing the basement.
Other
facilities available at Western Region
The
Region has the following analytical laboratories
Physics
Laboratory
Chemistry
Laboratory
Petrology
Laboratory
Remote
Sensing Laboratory
