"The valley has changed beyond recognition. It is a great shock for all of us," Yekaterina Radugova, director of the nature park, told Vesti-24.

Kamchatka, a 1,250 km (780-mile) long peninsula between the Pacific Ocean and the Sea of Okhotsk, is one of five places in the world where geysers -- springs ejecting hot water and steam into the air -- can be found. There were about 90 geysers in the valley.

"The biggest springs may still come through the debris but most of the others are probably lost forever," RIA news agency quoted an unnamed scientist at a local institute as saying.

The Emergencies Ministry in Moscow said it was unaware of the mudslide. Officials in Kamchatka could not immediately be reached for comment.

Scientists told RIA the slide had also destroyed deposits of siliceous sinter, or geyserite, a rare stone that takes many years to form. The geyserite cements the rock around the geyser and prevents erosion.

"Even a smallest dent in geyserite deposits in the geyser's crater can change the eruption's character," the scientist said. About 3,000 tourists come to the geyser valley every year.

Vesti-24 also quoted scientists as saying unusually warm weather in Kamchatka could have caused the slide. It said the torrent had also blocked the Geisernaya river and the water breaking through the dam could cause more damage in the valley.