How Are Glaciers Formed

Quake danger

Glacial lakes in the Himalayas could pose a major hazard to population centres if they are ruptured by earthquakes, scientists say.

The true risk to settlements and infrastructure downstream in the Hindu-Kush-Himalayas region is difficult to assess.

But the Himalayan region is dotted with glacial lakes and is in a seismically active zone.

Experts say that, on the basis of past records, a large quake in the region is overdue.

Many glacial lakes are said to be growing - some of them alarmingly - because of melting glaciers.

Some are at risk of rupturing, which would flood areas downstream.

There have been at least 35 glacial lake outburst events in Nepal, Pakistan, Bhutan and China during the last century, according to the United Nations Environment Programme (Unep).

But the increased risk from the quake-induced rupture of glacial lakes has been rarely discussed.

"Such a disaster is very much possible, more so, when we are expecting a big earthquake in the region now," says Sushil Kumar, a geophysicist with the Wadia Institute of Himalayan Geology in India.

"If the acceleration is very high in the epicentre of the earthquake, everything will be in the air as things will not be stable. So, naturally the liquids like waters in glacial lakes will burst out."

A number of these lakes are located near seismic faults.

"Given the location of the lakes, if the epicentre of the earthquake happens to be nearby them, they will certainly explode," says Pradeep Mool, a glaciologist with the International Centre for Integrated Mountain Development (ICIMOD) that works on mountain issues in the region.

A recent report produced by his organisation together with the World Bank and the Global Facility for Disaster Reduction and Recovery has also said, that such a hazard "is a possibility that should be considered, although prediction [of earthquakes] is beyond current competence."

Officials with Nepal's National Seismological Centre (NSC) say at least half a dozen minor tremors are recorded in the Himalayas every day.

"And when the tremor is [Magnitude] five or above... we record many aftershocks as well," says Dilliram Tiwari of the NSC.

"We know that these activities are happening in the Himalayas but we cannot confirm if they are happening nearby any glacial lakes.

How Glittering Glacier Caves Are Formed | UniqueDaily.com

“Glacier caves are living, changing parts of glaciers. They can be there one minute and gone the next, but they are some of the most incredible sights on glaciers, and the shapes and twists and turns the caves take are always exciting. Join us as we take a look at how these creations form with the help of Eric Guth, a devotee of glaciospeleology – the study of these magnificent icy caves … Eric explains the first method in a little more detail: “Glacier caves are formed by meltwater carving out or widening pre-established cracks/crevasses/fissures. They increase in size during the summer months when there is plenty of meltwater as they are often located near meltwater streams pouring into or out of glaciers. You look for moving water on a glacier and your chances of finding a cave increase.

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