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VLADIVOSTOK, April 2, vladivostoktimes.com Scientists have discovered caldera of an ancient supervolcano at Kamchatka, RIA Novosti reports.

"The eruption of the Kamchatka supervolcano took place more than about a million and a half years ago," Vladimir LEONOV, the Scientific Secretary of the Institute of Volcanology and Seismology of the Far Eastern Branch of the Russian Academy of Sciences, said to RIA PrimaMedia.

Now the volcano has "cooled off," so some specialists say it would be incorrect to speak of any possibility of new eruptions.

The report on the first study of the newly-found giant caldera was presented at the scientific conference dated to Volcanologist's Day, March 30, held in Petropavlovsk-Kamchatskiy.

According to Mr. LEONOV, people have known no such geological formations at Kamchatka up till now. The discovered caldera is a giant oval 35 kilometres long. The caldera is stretched between the head of the Paratunka River and Banniye hot springs. Scientists suppose that these particular springs might be heated by the warmth of the ancient super-volcano.

Supervolcanoes' calderas have kindled scientists' interest all over the world recently. The most well-known one is the Yellowstone Caldera measuring about 55 by 72 kilometres.

"Judging by geological data, the eruptions of the super-volcano happened there with an interval of around 640 thousand years. About 640 thousand years have passed since the time of the last eruption, and if no changes have occurred in the mechanism of the super-volcano, we can expect a new powerful eruption," a representative of the Institute said.

Supervolcanoes are giant cavities beneath the earth's surface that are continuously filled with magma that arrives from the bosom of the earth. The pressure formed there can induce eruption ten thousand times more powerful than any known volcanic eruptions. On the surface, supervolcanoes are recognized by calderas - giant craters that form when magma chambers sink.

The last supervolcano eruption occurred 74 thousand years ago in the region where Sumatra is located today. Then the average temperature in the Northern Hemisphere fell 21 degrees Centigrade. Some researchers also speculate that most living things perished then, brushing the evolution 2 million years back.