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The terrifying moment an avalanche thunders down a mountainside has been captured by brave photographers at Vallee de la Sionne, near Sion in Switzerland.

Incredible images reveal the snow crashing down the mountain at more than 50mph (80km/h) as scientists watch from a hut close to the avalanche's path.

The full-scale avalanche was triggered by scientists using explosives as part of an experiment to help them understand and model avalanche motion.

The terrifying moment an avalanche thunders down a mountainside has been captured by brave photographers near Sion in Switzerland

Researchers at the Swiss Institute of Research of Snow used seismic sensors - usually used to detect earthquakes - to record ground vibrations that could pick up an avalanche.

Meanwhile, photographers took pictures so that they could compare it with the seismic data to estimate the size of future events.

Another key measurement is snow temperature, and researchers collected data on this before, during and after the avalanche.

Scientists are hoping to learn more about how avalanches form. They believe the most deadly type of avalanche, dubbed a 'slab avalanche,' forms when an area of snow shatters and slides off the mountainside.

The avalanche was triggered by scientists using explosives as part of an experiment to help them understand avalanche motion

Images reveal the snow crashing down at more than 50mph (80km/h) as scientists watch from a hut close to the avalanche's path

Researchers at the Swiss Institute of Research of Snow used seismic sensors, usually used to detect earthquakes, to record ground vibrations that could suggest and impending avalanche. On the right, a helicopter monitors the scene

Loud noises aren't the main culprit in this type of avalanche. Instead, these avalanches tend to take place when snow builds up quickly, and weight is suddenly placed on the fresh snow.

When this happens, a weak area below the snow causes a slab to break off.

It is estimated that around 90 per cent of avalanche accidents involving people are triggered by the weight victim or someone with the victim.

The largest avalanches form from powder snow. They create turbulent currents that consist of a powder cloud, which overlies a dense avalanche. 

They can exceed speeds of 186 mph (300 km/h), and masses of 10,000,000 tonnes.

The study of avalanches can be dangerous in itself. Last month, a Colorado woman who studied the science of snow died after falling victim to the very thing she found so fascinating.

A small slide hit backcountry skier Olivia Buchanan of Durango and she later died at a hospital.

Ms Buchanan was studying geography, focusing on snow science, at Montana State University in Bozeman and had been an intern at the Silverton Avalanche School.

She was on the Rabbit Ears avalanche path, also known as the Arcade path, of Kendall Mountain near Silverton, Colorado when the tragedy struck.

The most common and deadly type of avalanche is called a 'slab avalanche,' when an area of of snow shatters and slides off the mountainside. Pictured is an artificially created avalanche in Switzerland

Scientists set up laser measurement and imaging equipment before triggering an avalanche at the Vallee de la Sionne in Anzere near Sion

The test took place at Vallee de la Sionne in Anzere near Sion. Anzère is a small village in the canton of Valais, Switzerland, located in the municipality of Ayent