Hyderabad: New research has hinted at the possibility of a diamond seam in the Nallamala forest region in Andhra Pradesh and the Godavari Graben, one of the largest sedimentary basins in India. Scientists involved in the research also claimed to have found a new, cost-effective and quick search tool, using earthquake data, for identifying regions where diamonds could potentially occur.
Geoscientists from city-based CSIR National Geophysical Research Institute (NGRI) studied seismic data related to recent earthquakes retri-eved from seismological stations located at Hyderabad, Kadapa, Kothagudem and Dharwar. Geoscientists Dr Subrata Das Sharma and Dr Durbha Sai Ramesh published their findings in the latest issue of the journal Lithosphere.
Diamonds are generally formed inside the Earth at a depth of more than 150 km, and forge through the surface by rocks known as kimberlites and lamproites. Earlier studies had suggested that the Indian lithosphere is thin, but Dr Sharma and Dr Ramesh’s work suggests otherwise.
Areas identified for exploring diamonds
A study by geoscientists Dr Subrata Das Sharma and Dr Durbha Sai Ramesh claims that geothermal conditions are conducive for diamond stability. They have identified an area spread across two lakh square kilometres where there is a possibility of finding diamonds.
“There are several conditions required for the formation of diamonds, foremost among which are high pressure, high temperature and appropriate partial pressure of oxygen within the Earth’s mantle. Our findings suggest that these conditions are fulfilled in south-eastern India,” Dr Das Sharma said.
However, he cautioned that “we are only hinting at the possibility of a diamond field in the Nallamala forest region and the Godavari graben. New exploration strategies are essential. These are only potential areas.”
The Nallamala forest region is the largest untouched forest reserve in South India and is known to have rocks formed by large scale volcanic activity millions of years ago.
The method used by Dr Das Sharma and Dr Ramesh could also be the quickest and most cost-effective for diamond exploration. Kimberlites and lamproites are extremely difficult to locate but the techniques by the NGRI geoscientists could be path-breaking for their pace and cost-effectiveness.