VIJAYAWADA: The studies carried out by the Geological Survey of India (GSI) have found out a different yardstick for Amaravati. Known for its rich geological significance, now Amaravati is under the keen observation of enthusiastic geologists across the state and even from abroad. The present capital region development area is already identified as a significant zone because of the extensive works carried out by the GSI. The GSI studies have found out three prominent geological formations culminating in the new capital city.
These are Precambrian rocks characterised by Khondalites and Charno-ckites trending north-east and south-west followed by Proterozoic kadapa rocks in the south. While, the north-eastern portion of kadapa is prominent in Guntur district, in the western part there are rocks belonging to Kurnool which are equivalent to Vindhyan group. Thus Amaravati is kno-wn to have the oldest Precambrian rocks, that is almost 3,000 million years old, and also relatively younger Proterozoic rocks, which are 600 million years, simultaneously in this zone. Interestingly, these two formations are followed by minor exposures of Gondwana rocks, which are 200 million years old. The recent alluvium of Delta was also the outcome of these rocks. More explorations in these areas will certainly support the newly formed State’s economy, according to Professor L.S.N. Prasad. “The Chief Minister can concentrate on this aspect, which would be helpful for the state,” he observed.
Geologically, Amaravati can be considered as the most important geological heritage site, the Precam-brian rocks were the host of ore mineral Chromite occurring near Konda-palli. The Proterozoic rocks of kadapa basin, which was exposed as Agnigundala belt near Vinukonda of Guntur district were known for base metal mineralisation like copper, lead and zinc sulphide. Similarly, in the western part of Bellamko-nda, the Kurnool rocks are famous which were historically known for Diamond occurrence. The world-famous Kohinoor diamond was supposed to be mined in the place called GaniKolluru (Gani-Coulour) during Nizam times.
The Kondapalli region in the Eastern Ghatsof Andhra Pradesh consists of high-grade granulite facies rocks — charnockites, in which chromite occurs. Chromite is most important ore of Chromi-um which is used as the refractory metal and for the manufacture of Ferro Chrome Alloys. A number of mines near Kondapalli were active in mining for several years. Experts believe exploration is needed to locate more such deposits or extensions of this deposit.
The Kohinoor diamond was once the largest known diamond in the world. It originated in India. Most historians say that the diamond comes from the diamond mines of Golconda. Gordon Mackenzie who worked as the Collector of Krishna district towards the end of the 19th century, recorded in his ‘Manual of the Kistna District in the Presidency of Madras’ that the Kohinoor diamond was found in Gani-Kolluru mine on the banks of River Krishna.
The Vinukonda is famous for Copper, Lead and Zinc mineral sulphides belonging to Agnigundala Belt. Geologically they belong to North East portion of Cuddapah basin. Mining was done by Hindustan Zinc Ltd for several Years. Experts believe exploration is needed to locate more such deposits or extensions of this deposit.
