10-March-2017: Canyon system found near Kovvada
Scientists of CSIR-National Institute of Oceanography (NIO) in Visakhapatnam have found three new canyons forming a major canyon system in the depths of Bay of Bengal close to Kovvada in Srikakulam district.
The finding has been evading them since the last 50 years, and for the first time they have clearly mapped the ocean floor between Visakhapatnam and Srikakulam by sending over 32 high density beams to the depths of the sea.
Canyon systems are generally formed by flow of river water into the sea and they could be as old as the river system, which is close to 23 million years. But what makes our find interesting is that we could locate and clearly map a new system in the Bay of Bengal off the coast of Visakhapatnam and after nearly five decades.
The last canyon systems off the Visakhapatnam coast were discovered in 1963 by American geologist E.C. LaFond of U.S. Navy Electronics Laboratory, who was carrying out marine studies at Andhra University. The data was collected on board research ship Anton Bruun. Prof. LaFond then discovered three canyon systems between Viskhapatnam and a few kilometres north of Bheenumipatnam. Prof. LaFond had then stated that there were three other canyon systems, but we did not have any proof. But now we have discovered them and also, prominently mapped them with the help of state-of-the-art facilities on board RV Sindhu Sankalp research vessel.
The new canyon system is very huge and probably formed by the river Kandivalasa. The depth of the canyon varies from about 90 metres from the starting point to about 2,500 metres at the deepest point, and it extends to about 50 to 70 km deep into the sea and the width varies from 50 metres to 2 km.
As per the findings, the depth is more than the Grand Canyon, which is about 1,857 metres. Most of the canyons in the ocean system across the world act as channels for depositing sediments in the shelf region. The more the deposit, the more are the chances of finding hydro-carbons. But it is too early to say on this aspect, as we have just discovered the canyon and the shelf region is yet to be explored.
The discovery of the canyon is not only a major breakthrough in underwater geological formations, but also gives us immense scope to study and explore new benthic ecosystem. The study of ecology and fauna and microorganisms will not only tell us about our past but also throw light on new science. The study of how organisms live and flourish at low oxygen level and high current system can lead us to understand human heart diseases better and help us develop new treatment system.
19-Feb-2017: Barren Island volcano becomes active again.
Barren Island volcano in the Andaman and Nicobar Islands has started spewing smoke and lava again.
After lying dormant for 150 years, Barren Island volcano erupted in 1991 and has been showing sporadic activity since then. The volcano is erupting in small episodes of five to 10 minutes. During the day, only ash clouds were observed. But after sundown, red lava foundations were spewing from the crater into the atmosphere and hot lava streamed down the slopes.
Researchers from Council of Scientific & Industrial Research (CSIR) and NIO have sampled sediments and water in the vicinity and recovered coal-like black pyroclastic material representing proximal volcanic ejecta. These samples will help in deciphering the nature of present and past volcanic activity in the region.
The Andaman basin is an active back-arc spreading basin known for strong seismicity, submarine volcanoes and hydrothermal activity. Scientists from CSIR-NIO have been surveying the basin and have identified several small submerged volcanoes in a linear chain called a volcanic arc. These volcanoes are formed due to the rising magma formed deep in the mantle due to the melting of the subducted Indian Ocean crust. A few of these submarine volcanoes have been dredged for samples and a pumice type of light volcanic rock has been recovered.
The volcanic island is uninhabited and its northern part is, as the name suggests, barren and devoid of vegetation. Indian citizens can visit the island by chartered boats after obtaining permission from the forest department in Port Blair.
18-Feb-2017: Scientists claim discovery of a submerged continent "Zealandia" in Pacific Ocean.
A continent two-thirds the size of Australia has been found beneath the south-west Pacific Ocean, scientists reported in the journal of the Geological Society of America.
Known as Zealandia, the land mass of 4.5 million square kilometres (1.74 million square miles) is 94 per cent under water and only its highest points — New Zealand and New Caledonia — poke above the surface.
Since about the 1920s, from time to time in geology papers, people used the word ‘continental’ to describe various parts of New Zealand and the Catham Islands and New Caledonia. The difference now is that we feel we’ve gathered enough information to change ‘continental’ to the noun, ‘continent'.
Geologists early in the previous century had found granite from sub-Antarctic islands near New Zealand and metamorphic rocks on New Caledonia that were indicative of continental geology. If the recent discovery is accepted by the scientific community, cartographers will probably have to add an eighth continent to future maps and atlases.
Zealandia is believed to have broken away from Australia about 80 million years ago and sank beneath the sea as part of the breakup of the super-continent known as Gondwanaland.