Fibre optic cables could help detect earthquakes

Researchers in Iceland hope that fibre optic cables may make earthquakes easier to detect than ever before.

 

Much of the technology that we take for granted in the 21st century relies on fibre optic communications cables, from long-distance phone calls and television services to the internet. Fibre cables laid beneath the ground enable business and industry to move large amounts of data quickly.

 

Now researchers in Iceland may have found a new use for the technology. According to an article in the peer reviewed journal, Nature Communications, underground broadband networks could be used in future to detect seismic activity.

 

The challenge is to find a cheaper alternative to expensive seismometers placed at sensitive locations. The research team carried out tests on 15km of fibre-optic cable that had originally been installed between two geothermal power plants, in Iceland, in 1994.

 

The team led by Dr Philippe Jousset, from the GFZ German Research Centre for Geosciences, discovered that a laser pulse sent down a single fibre of the cable was sufficient to determine whether there were any disturbances along its length.

 

When movements in the ground stretched or compressed the cables, the scientists were able to record it. They found that the cables not only recorded seismic signals, but were also able to detect the surrounding faults and other underground geological structures.

 

There are hopes that once refined, the technology could be used for low-cost earthquake early warning systems.

 

International Standards for fibre optics

 

Manufacturers and suppliers of optical fibres and their components can rely on the IEC to provide the tools necessary to ensure the quality and reliability of their products.

 

IEC Technical Committee (TC) 86: Fibre optics, its three Subcommittees (SCs) are central to the development of the entire sector and all related industries as they prepare Standards, specifications and technical reports for fibre optic-based systems, subsystems, modules, devices and components.

 

Recent highlights include:

 

IEC SC 86A has standardized the most recent development in wideband multimode fibre, known as OM5. IEC 60793-2-10 increases data rates by augmenting the capacity of each fibre by a factor of four. Because it can be incorporated into existing equipment, it remains compatible with older applications.

 

Technical Report IEC TR 63072-1, developed by SC 86C, provides an introduction to photonic integrated circuits (PICs) and describes a roadmap for the standardization of PIC technology over the next decade. PICs bring together optical and electronic functionalities. This technology has the potential to enable computing and data transmissions at great speeds which will be essential for the implementation of the next generation of smart services including 5G networks.

 

High quality components

 

To ensure the quality and reliability of the components used in optical fibre assemblies, manufacturers and suppliers have a powerful tool at their disposal. IECQ, the IEC Quality Assessment System for Electronic Components, provides certification at the international level for a wide variety of electronic components, including those found in fibre optic systems.

 

IECQ offers immediate international recognition. One test and one certificate issued in one country means acceptance on a global basis, even in countries that are not IECQ Members.

 

Reducing the use of hazardous substances

 

Nowadays, electronic component manufacturers who have had their products tested and certified by IECQ also request IECQ HSPM (Hazardous Substance Process Management) certification to demonstrate that their products are produced under controlled conditions to provide assurance that they meet hazardous-substance-free specific local, national and international requirements.

 

This is of particular importance for fibre optics as networks increasingly extend across borders. For this reason they have to comply with different national regulations that may restrict or prohibit the use of such substances in components.

 

The IECQ System provides all players in the ever expanding fibre optic market with the certainty of using electronic components that meet the strictest requirements and are of the highest quality.