Seeking to understand the monsoon better, Indian scientists will dig a deep bore hole in the Arabian seabed to collect sedimentary samples that would help rebuild climate variation over the past few thousand years.
Scientists have drawn up plans to extract sedimentary samples from the Laxmi basin located about 400 nautical miles southeast of Mumbai coast.
“We are negotiating for hiring one of the two scientific drilling ships for collecting samples from a depth of up to three km under the seabed,” Shailesh Nayak, Secretary in the Ministry of Earth Sciences, told PTI here.
He said once the ship is hired, scientists would be able to start the ocean drilling programme and collect samples over a three-month period.
The main objectives of the programme are to reconstruct the entire history of the monsoon over a few thousand years and study the evolution of the Himalayas.
The programme is also expected to shed light on the evolution of the topography of the Himalaya-Tibet plateau which controls the climate in South and East Asia.
A long-term reconstruction of mountain building, erosion, and deposition synchronous with monsoon activity is key to testing the links between climate and Tibetan evolution, scientists said.
Thus, basins surrounding the Himalaya — the Arabian Sea and Bay of Bengal — are excellent repositories for studying the relationship between tectonics and climate, according to the proposal for the Integrated Ocean Drilling Programme.
Sediments in these basins which are brought by rivers flowing through the world’s highest terrain record the history of the world’s most spectacular continental collision zone, it says.
“If we can reconstruct the past 1,000 years of climatic data, it would be a good handle to improve forecast of monsoon,” Nayak said.
He said only two drilling ships are available worldwide — JOIDES Resolution operated by the US National Science Foundation and Chiyku of the Japan Marine Science and Technology Centre — which are heavily booked.
The hiring of ships for a period of two to three months is expected to cost Rs 50 crore, Nayak said, adding that the real work of analysing the Integrated Ocean Drilling Programme cores would take a few years.