using geothermal resources,” she added.

From the heat of the earth

Hot springs and geysers are present all over the world in volcanically active regions, especially in countries like Iceland, whose famous erupting Geysir gave the phenomenon its name.

Water seeps below the surface through rocks, penetrates deep into the ground where the Earth’s inner heat starts to warm it, and is pushed upwards to the surface.

Around 65 million years ago, the coastal region of the Western Ghats was a series of active volcanoes called the Deccan Traps. Even today, this is one of the largest volcanic structures on the planet, covering a total area of 5 lakh square kilometres — roughly the expanse of Spain — through Maharashtra, Goa, Karnataka, and Madhya Pradesh.

When these volcanoes were active, they had incessantnow, it was believed that water seeped in only until this rock, and flowed through basaltic rocks, before emerging out again. However, Chandrashekhar and her team’s analysis of the area paints a different picture.

Below the basalt in the region are sedimentary layers of sandstone and limestone called the Kadalgi sediments. And further below these sediments are rocks called Precambrian granite that are billions of years old. It turns out that water seeps in and runs along this solid basement rock as well.

As the water flows linearly through the 350 km distance, through the Palghar, Raigad, and Ratnagiri districts of Maharashtra, getting heated all the while, it also picks up marine sediments

All of these combined impart into the seeping water minerals like boron, calcium, sodium, and chlorine. There are