Background
The National Geophysical Center (CNG) was established in 1975 and is the oldest among the four CNRS centers. The CNG is both an observatory and a research laboratory continuing the studies initiated in 1920 in the Levantine region by the Observatory of Ksara. In addition, the CNG provides the public and the authorities, almost in real-time, the objective data needed to evaluate the exposure of the country when an earth tremor is felt. Moreover, the Center deals around the clock with extreme events, and is involved in all actions aiming at raising the awareness and preparedness of fellow citizens by promoting risk culture either among the youth in schools, or in official fora. Furthermore, it conducts all geophysical studies that may help alleviate the impact of seismic hazards in the Lebanese tectonic environment, such as the monitoring of the active faults using crustal deformation surveying techniques.
Research partnership
The main foreign longtime partner of CNG is the Institut de Physique du Globe de Paris IPGP. This institute helped starting the development of the GRAL network, launching the GPS crustal deformation application, supporting the geomagnetic Observatory of Qsaybeh, digging tectonic trenches on the Yammouneh lake site and elsewhere, introducing us to other French (IFREMER, CEREGE...). IFREMER made available its naval means to map Lebanese offshore. With the CEREGE, we extended our field of interest to paleoclimatology with an important already published study about the climate of Lebanon since 200000 years. Since 2005, projects are conducted with ISTerre, CEREMA and Geoazur, to improve our understanding of the seismic hazard in Lebanon. Lately, a new collaboration has started between the CNG and Mine ParisTech in the field of Seismology.
Research Activities and Projects
1- Early warning systems
While seismic forecast is still a far reach aspiration, it is possible to monitor correctly tsunami generation and propagation resulting from a submarine earthquake or an underwater landslide. The Center hosts and runs the FTWP or Tsunami Warning Focal Point for Lebanon and is responsible for maintaining a continuous watch in order to receive and evaluate alert messages from regional tsunamis alert centers before routing them to Civil Defense and other authorities. For this purpose, the Center is an active partner in the NEAMTWS group of experts established by the IOC.
Another seismic network based activity is monitoring banned experimental nuclear blasts. Lebanon is a signatory of the Comprehensive Test Ban Treaty and our center now hosts the ad hoc National Data Center. Nuclear experiments being exceptional events, the high-quality data from the CTBT Organization has been made available for a wide range of applications.
2- The national seismic network
A network of 12 permanent stations constituting the core of the so-called Geophysical Research Arrays of Lebanon or GRAL was established, which greatly improved real time monitoring and epicentral determinations. The GRAL network produced a realistic representation of the seismicity of Lebanon.
3- Monitoring crustal deformation
The first GPS campaign was established in 1999, then repeated in 2001 and 2010. The Northern profile extends from the Ramkine islet to East of Ras Baalbek whereas the Southern one runs from Damour to Deir el Aachayer. It was important to check the difference in deformation style North and South of the parallel of Beirut, which was clearly visible in the geomorphological coastal features and was reflected on the seismicity map.
4- Marine studies
Within the framework of a French-Lebanese partnership, the RN Le Suroît of the IFREMER fleet surveyed an area extending 100 km off the shores of Lebanon in order to complement the land studies about the exposure of the country to seismic risk. One of the main outcomes of this survey (code-named SHALIMAR for Seismic HAzard Liban MARin) was the new multi-beam bathymetric map of Lebanon.
Recognizing the necessity to connect offshore structures to the inland observed ones, it was possible to start to complete the bathymetric map within the Italian funded CANA-CNRS vessel, equipped with a costly multi-beam echo-sounder system with its sophisticated positioning system.
5- LebQuake Mobile Application
An application for mobile phones, LebQuake, has been developed, with the aim of informing citizens about seismic activity on the Lebanese territory.
6- Seismological Bulletins
The Geophysical Research Centre publishes a monthly provisional Seismological Bulletin available online at the end of each month on this website.
Personnel
BRAX Marleine Director
JOMAA Rachid Assistant researcher (Engineer)
CHAMOUN Jean Assistant researcher (Engineer)
LABAKI Hiba Assistant researcher (Engineer)
NOHRA Walid Technician
ALLAM Cyrille Technician
Contact Us
Address: Bhaness Hospital Campus, Dahr El Sawan, Metn, BEIRUT LEBANON
P.O. Box: 16-5432
Tel: +961 4 981885
Fax: +961 4 981886
E-mail: geophys@cnrs.edu.lb