Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Calculating flood waves in Lyngen

12.09.2007
It is hoped that detailed mapping of the fjord floor in Lyngen in Troms, northern Norway, will show how flood waves generated by avalanches crashing into the sea may affect the land. The unstable section of Nordnesfjellet, 600-800 metres above the beautiful fjord, is moving up to three centimetres a year.

Seisma, a research vessel belonging to the Geological Survey of Norway (NGU), is sweeping Storfjord with seismic and state-of-the-art, side-scanning sonar. Metre by metre, scientists are studying the floor of the fjord.

Well prepared

On the basis of these detailed maps, staff from the Norwegian Geotechnical Institute (NGI) will construct a precise terrain model of the sea floor. They can use this to calculate how flood waves will build up and sweep over the shores if Nordnesfjellet should one day crash into the sea.

“It’s vital to get as much information as possible about both the mountain and the floor of the fjord. This will enable us to be prepared in case the worst should happen,” Oddvar Longva, a geologist at NGU, tells me. He is the skipper of the Seisma and has a great deal of experience of surveying conditions on the floor of Norwegian fjords.

Large flood waves

The worst scenario here is that several million cubic metres of mountainside will one day sweep over the E6 trunk road and end up in the fjord. This will generate a flood wave that will hit the boroughs of Lyngen, Kåfjord and Storfjord. As many as 6000 people, along with buildings, industrial plants and farmland, may be inundated.

”It’s not very likely that the mountainside will crash into the fjord in the very near future, but if it does the consequences will be enormous. There is therefore a great deal of risk associated with an unstable section of mountainside,” Terje H. Bargel, a geologist at the Geological Survey of Norway (NGU), stresses.

”When we’ve learnt how an unstable section of mountainside behaves, and mapped the terrain below sea level, it will be easier for local authorities to draw up contingency plans to provide warning and ensure evacuation,” he continues.

The danger

Terje Bargel heads the avalanche group at NGU and is very satisfied that the authorities are now putting priority on investigations of major avalanches.

”The Government has allocated an additional five million NOK this year to study the risk of major avalanches. NGU is concentrating particularly on large avalanches involving more than 100 000 cubic metres of rock that may crash right down into fjords and generate tsunamis. We’ve studied 13 sites in the county of Troms in northern Norway that have the potential to develop major avalanches. Lyngen is by far the most important area,” Terje Bargel says.

Installing equipment

It is the northern part of Nordnesfjellet that is moving. NGU has studied the mountain on several occasions by both mapping the geology and gathering geophysical data.

The hazardous stretch of mountainside is four hundred metres broad, five hundred metres high and between fifty and one hundred metres deep. New instruments are now being installed to monitor the mountainside.

Laser meters will monitor movements in the mountainside and tension rods will measure the widening of the fissures. Meteorological instruments are also being set up to monitor the wind, temperature and precipitation.

By Gudmund Løvø

Terje Bargel | alfa
Further information:
http://www.ngu.no

More articles from Earth Sciences:

nachricht Impacts of mass coral die-off on Indian Ocean reefs revealed
21.02.2017 | University of Exeter

nachricht How much biomass grows in the savannah?
16.02.2017 | Friedrich-Schiller-Universität Jena

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Organ-on-a-chip mimics heart's biomechanical properties

23.02.2017 | Health and Medicine

Light-driven reaction converts carbon dioxide into fuel

23.02.2017 | Life Sciences

Oil and gas wastewater spills alter microbes in West Virginia waters

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>