2. INTRODUCTION
It is exposed in an area of just over 5000 sq. km.
In parts of northern Karnataka and consist of mainly
limestones and shales with thin arenites and
conglomerate at the base.
Unmetamorphosed
and undisturbed
sediments , resting
upon the Archaean
crystallines and
capped by the Deccan
Traps in this region.
3. CONTINUE.....
It is one of the smallest of the
independently recognised “purana basins
of peninsular india”.
Minerlisation has taken place in faulted
areas of the basin like Kurlagere-Gogi
fault.
4. GEOLOGICAL AGE
U–Th–Pb and Rb–Sr (strontium) radiometric
dates of limestones and glauconite‐bearing
sandstones of the Bhima Group (Bhima
Basin). Indicate deposition at around 800–
900 Ma.
That means it belongs to the neoproterozoic
Era of Proterozoic Eon.
5. TECTONIC CONDITION
The age of the Bhima Basin has the time
period of Pannotia /Pan-Africa
supercontinent.
The sigmoidal nature of the Bhima Basin
contact is significant and is attributed to the
pull apart mechanism.
The isostatic adjustment of the area leads to
the faulting during pre-, syn-, post-
sedimentry periods.
6. CONTINUE......
The fracturing and development of foliation
charcteristically seen in granites point out
involvement of reactivation processes which
leads to the ore grade uranium deposits
along the fault zones such as Gogi and other
places,
7. LITHOSTRATIGRAPHY
FORMATION MAXIMUM
THICKNESS
MEMBER MAIN LITHOLOGICAL COMPONENT
Shahabad
limestone
<75m. Gray , argelliceous micritic lst.
Dark bluish gray, massive limestone
Variegted, siliceous and cherry lst
Blue grey, blocky miritic lst
Flaggy limestone
Rabanpalli
Clastics
<70m. Ekmai shale member Ferrogenous shales, with calcareous shales
at top
Kasturplli Green, glauconitic bearing fine sst and
siltstone
Kundrapalli Quartz
arenite member
Quartzitic sst (medium to fine grained)
Adki Hill
conlomerate member
Polymictic conglomerates and arkosic,
grity sst
9. MINERALIZATION
1. There is association of Uraniam with
Phosphatic limestone at Ukinal along fault
zone.
2. Hematite, coffinite and pichblend are low
temp. Minerals suggest the temperature of
formation of Ur is low.
3. The Shahabad limestone used in the
cement industry.
12. REFERENCE
Kale & Mudholkar, 1990, Stratigraphy of the
Bhima Group
K.K. Dwivedy, K.K. Achar, S.A.Pandit,
V.Natrajan, M.K. Kumar, BHIMA BASIN,
KARNATAKA, INDIA URANIUM
MINERALISATION IN THE
NEOPROTEROZOIC
Geology of India, vol. 1, M Ramakrishnan &
R Vaidyanadhan