Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Permanent deep-sea seismic sensors

07.06.2005


A submarine seismic sensor was recently set in place at 2400 m depth, off Toulon. The instrument was attached to a neutrino telescope developed by the international scientific programme Antares (1) . For the first time in Europe, this sensor, designed by a partnership between Géosciences Azur (Mixed Research Unit IRD/CNRS/UPMC/UNSA, Villefranche sur Mer)(2) and Guralp System (United Kingdom), with the financial support of INSU, Villefranche Oceanological Observatory and the Provence-Alpes-Côte d’Azur Regional Council, can send real-time deep-sea seismic activity data recorded for the region and for the whole world.



Deployment of this broad-band sensor by the IFREMER ROV (3) "Victor" allows testing of the installation parameters necessary for accurate observation of earthquakes that occur locally, within the region or elsewhere throughout the globe. The project has also resulted in new developments in deep-ocean technology and skills.

Three great challenges face scientists in efforts to achieve high-quality long-term observation: resistance of instruments and cables to enormous deep-sea water pressures; resistance of instruments to corrosion in the marine environment; and perfect coherence between the equipment and the electronic systems incorporated to ensure remote control and monitoring.


The Antares programme conducted off Toulon, for which the CPPM (4) at Marseille-Luminy University is the host laboratory, gave the Géosciences Azur team a unique opportunity to take up these challenges and develop seismological techniques that could subsequently be ’exported’ for application in the world’s earthquake zones. In several coastal regions of the globe, seismic risk comes from strong submarine earthquakes that can occur. Accurate study of such activity is therefore important for devising improved risk-assessment systems. That is why marine sensors are necessary.

The observation tools scientists currently have at their disposal for conducting research programmes are stand-alone seismological sensors or OBSs (Ocean Bottom Seismometers), cast off from the surface with their batteries and built-in memory which confers several months’ recording capacity. They come to rest freely on the ocean floor. At the end of the prescribed recording period they are brought to the surface by remote control. However, data analysis cannot be performed until the seismometer has been retrieved.

Even though it is not a means of earthquake prediction, seismological surveillance can allow rapid assessment of an event’s magnitude and location; and hence of their impact. It requires real-time transmission of data provided by the sensor networks in place.

In this aspect too, the experiment under way is bringing with it an improvement in reliability of the technological systems used: digital ground movement recordings made by the sensor are transmitted by a 40 km long cable which links all the elements of the Antares experiment to the coast; from there they are relayed by the Internet to the Géosciences Azur laboratory.

The laboratory’s next objective is to deploy a similar sensor in the Ligurian Sea in order to complete its regional earthquake watch system.

Notes

1. Antares is a joint research venture between 14 European laboratories. In France it brings together researchers, engineers and technicians from the CEA (DSM/Dapnia), the CNRS (IN2P3 and INSU), universities –of Toulon and the Var (La Garde), the Mediterranean (Marseille), Haute-Alsace (Mulhouse), Denis Diderot Paris 7 (Paris) and Louis Pasteur (Strasburg) – as well as marine environment and technology experts from IFREMER. The project is financed by contributions from: the CEA (DSM/Dapnia) and the CNRS/IN2P3; the Regional Councils of Alsace, Provence-Alpes-Côte d’Azur ; the council of the Département du Var; the town of La Seyne-sur-Mer; the European Union; and five countries (Netherlands, Germany, Italy, Spain, Russia).

2. Institut de recherche pour le développement (IRD), Centre national de la recherche scientifique (CNRS), University of Nice-Sophia Antipolis (UNSA) and the Pierre et Marie Curie University of Paris (UPMC).

3. Remotely Operated Vehicle: submersible remote-controlled from the surface.

4. Centre de physique des particules de Marseille, Mixed Research Unit (CNRS/IN2P3 and the University of the Mediterranean).

Hélène Deval | EurekAlert!
Further information:
http://www.ird.fr

More articles from Earth Sciences:

nachricht Novel method for investigating pore geometry in rocks
18.06.2018 | Kyushu University, I2CNER

nachricht Decades of satellite monitoring reveal Antarctic ice loss
14.06.2018 | University of Maryland

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Creating a new composite fuel for new-generation fast reactors

20.06.2018 | Materials Sciences

Game-changing finding pushes 3D-printing to the molecular limit

20.06.2018 | Materials Sciences

Could this material enable autonomous vehicles to come to market sooner?

20.06.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>