The Combined Use of Ground-Based and Remote Sensing Techniques as a Tool for Volcanic Risk and Health Impact Assessment for the Goma Region (North Kivu, Democratic Republic of Congo, Africa) - GORISK

Coordinating Institution: Musée national d'histoire naturelle
Contracting Partner(s): Royal Museum for Central Africa (B) , Université Libre de Bruxelles (B) , University of Naples (Italy) , Unops , World Organization of Volcano Observatories , University of Luxembourg
From: 01/12/2006
To: 30/09/2009
Budget: 85,300.00€
Contact(s): D'Oreye Nicolas

Summary

The region of Goma lies under the direct threat of volcanic hazards from two out of the most active volcanoes in Africa. The January 2002 eruption of the Nyiragongo produced lava flows that destroyed 15% of the city (600.000 inhabitants). Although the amount of casualties was limited, hundred thousands of refugees were pushed out of the area which added some more pressure in a highly politically sensitive region. The mitigation of the volcanic risks depends on the availability of an efficient monitoring system. The GORISK project, co-funded by the Belgian Science Policy and the FNR in the frame of the STEREOII program, is oriented towards the improvement and implementation of techniques dedicated to the study and monitoring of the Nyiragongo, combining ground based and space-borne techniques.

An important GORISK segment, mostly ensured by the NMNH, concerns the monitoring of the ground deformations. It is addressed both by space borne (satellite radar interferometry) and ground based (tilt and GPS) observations. Volcanic plume fallouts are also a big concern as it causes damage to vegetation and cultivations. GORISK takes benefit from ongoing EU and US-NSF projects (NOVAC and VISOR) that are respectively focused on ground- and space-borne monitoring of the plume. These observations are combined to additional geochemical ground measurements of water quality, CO2, CH4 and radon (mostly ensured by the universities of Luxembourg and Napoli). GORISK also involves the study of the possible impact of the volcanic activity on health.

Achievements in 2009:

End of 2009, we processed at the NMNH the hundreds of satellite radar (SAR) archives and images regularly acquired (~1/week) for the needs of our project. Out of that 11-years long databank, we computed >2000 interferograms (combination of two SAR images of about 100x100km allowing under certain conditions the observation of ground deformations at the sub-centimetre level). Out of these 4 TerraByte of data we successfully detected the ground deformations associated to the most recent eruptions of the Nyiragongo (2002) and Nyamulagira (2002 and 2006), which are under study in collaboration with the university of Clermont-Ferrand and RMCA. It also allowed to study the magnitude 5,9 Earthquake that struck the city of Bukavu (South of Lake Kivu) on February 3rd 2008. Two fieldwork missions were also carried out in Goma area for the maintenance, the upgrade or the re-installation of some of the 5 continuous tilt monitoring stations and the 7 permanent GPS geodetic stations (from NMNH) radioed in real time to the GVO: From April 21 to May 8 and from September 14 to October 7.

Indeed due to the conflict in DRC, some of the stations had to be temporarily dismounted to avoid looting. Lightning also damaged some stations. The complementary help from the Development Cooperation service from the Luxembourgish Foreign Affaires Ministry allowed to carry on the monitoring despite the financial difficulties at GVO. Another mission in Kinshasa took place from March 18 to 20 to discuss with the Minister of Scientific Research of Congo about the problems and difficulties encountered in the frame of GORISK for the monitoring of the Virunga volcanoes.

The structure of GVO was recently modified in depth bringing us very good hope for the future. Seminars were organized in Goma during these missions for training the local staff to the maintenance and use of the tilt- and GPS-networks. N. d’Oreye was invited in TU Delft to give a seminar about the difficulties of monitoring active volcanoes in Africa (December 15th, Aerospace Ing. Dept., Technical University of Delft, the Netherlands) and an invited keynote lecture opening the MIAVITA workshop in Cape Verde (WORKSHOP ON VOLCANIC HAZARD MITIGATION, June 20 – 24, 2009, Hotel Xaguate, São Filipe, Fogo Island, Republic of Cape Verde).

Collaborations:

GORISK benefits from synergies with ongoing projects such the here above-mentioned EU NOVAC project and US-NSF VISOR project that are respectively focused on ground- and space-borne monitoring of the volcanic gas plume. GORISK also benefits from strong synergies with:- the ESA Category-1 SAMAAV project (« InSAR Analysis and Monitoring of Active African Volcanoes using ERS and ENVISAT data ») coordinated by the RMCA (B) and the NMNH (L). It is dedicated to the study and systematic monitoring of the Nyiragongo-Nyamulagira (DR Congo), the Fogo (Cape Verde), the Ol Doinyo Lengai (Tanzania) and the Mt Cameroon and involves partners from Europe and Africa: the University of Liège and Ghent in Belgium, the Instituto Superior Tecnico of Lisbon, the University Blaise Pascal in Clermont-Ferrand, the Dar es Salaam University and the Geological Survey of Tanzania, the Instituto Nacional de Meteorologia e Geofísica de Cabo Verde, the Goma Volcanological Observatory (Dem. Rep, Congo) and the University of Buea (Cameroon). - the ESA/JAXA project « ALOS: The ALOS contribution to the monitoring of volcanic zones and to the volcanic hazard assessment in the African context. An integrated method for optics, and microwave sensors ».

The InSAR tools and processing method used for GORISK are the same as the one we developed for the SAMAAV and ALOS projects. Among the most important results we achieved in 2008 with these tools is the first detection of a dyking event ever recorded within the planet's continental crust. This was published in the renowned “Nature” journal :E. Calais, N. d’Oreye, J. Albaric, A. Deschamps, D. Delvaux, J. Déverchère, C. Ebinger, R. W. Ferdinand, F. Kervyn, A. S. Macheyeki, A. Oyen , J. Perrot, E. Saria, B. Smets, D. S. Stamps & C. Wauthier, "Aseismic strain accommodation by slow slip and dyking in a youthful continental rift, East Africa"Nature, Vol. 456, Iss. 7223, 2008That work was also the occasion to contribute to many international meetings in 2008 with 3 invited lectures, 5 regular talks and one poster (not listed here below).

Programme:

  • STEREO II, Recherche en Observation de la Terre

Foreign Funding Agency:

  • Service Fédéral Public de programmation Sceintifique (Belgium)
Refereed Scientific Publications
  • Smets B., Wauthier C., d’Oreye N. : A new map of the lava flow field of Nyamulagira (D.R.Congo) from satellite imagery Accepted for Journal of African Earth Sciences
  • A.-C. van Overbeke, M. Bagalwa, J. Durieux, D. Kavotha, F. Kervyn, A. Kies, F. Lukaya, P. Mitangala, N. d’Oreye, E. Osodundu, B. Smets, D. Tedesco, C. Wauthier, M. Yalire: Monitoring of volcanic activity in the Goma region (N-Kivu, Democratic Republic of Congo) and mitigation of related risks by both spaceborne and ground-based techniques: experience of the GORISK project. Accepted for the Cahier du Centre Européen de Géodésie et de Séismologie
  • C. Wauthier, V. Cayol, F. Kervyn, N. d'Oreye: Modeling of InSAR displacements related with the January 2002 eruption of Nyiragongo volcano . Accepted for the Cahier du Centre Européen de Géodésie et de Séismologie
  • N. d’Oreye, G. Celli : Automatic InSAR systematic processing and web based tool for efficient data mining: application to volcano monitoring in Africa. Accepted for the Cahier du Centre Européen de Géodésie et de Séismologie Also available in ESA Special Publications SP-677 on CD-ROM.
  • + 2 others in preparation and 1 submitted
Other Publications:

Abstract and proceedings (2009 only)

  • N. d’Oreye, P. Gonzalez, A. Shuler, L. Bagalwa, G. Ekstöm, D. Kavotha, F. Kervyn, F. Lukaya, E. Osodundu, A. Oth, C. Wauthier: The Mw 5.9 February 3rd 2008 Bukavu Earthquake . Abstract for 2009 IEEE International Geoscience & Remote Sensing Symposium, July 13-17 2009, Cape Town, Africa
  • N. d’Oreye, E. Calais, V. Cayol, J. Fernández, C. Frischknecht, P. Gonzales, S. Heleno, F. Kervyn, P. Marinkovic, A. Oyen, C. Wauthier: Seismic and volcanic activity in Africa monitored by InSAR. Abstract for 2009 IEEE International Geoscience & Remote Sensing Symposium, July 13-17 2009, Cape Town, Africa
  • V. Cayol, N. d'Oreye, F. Kervyn, C. Wauthier and the GVO Team: InSAR displacements associated to the November 2006 Nyamulagira eruption. Abstract for 2009 IEEE International Geoscience & Remote Sensing Symposium, July 13-17 2009, Cape Town, Africa
  • C. Wauthier, A.M. Oyen, P.S. Marinkovic, R.F. Hanssen, N. d'Oreye, F. Kervyn, J. Fernandez, V. Cayol: L-BAND CONTRIBUTION TO C-BAND INSAR STUDIES OF AFRICAN VOLCANIC AREAS. Abstract for 2009 IEEE International Geoscience & Remote Sensing Symposium, July 13-17 2009, Cape Town, Africa
  • C. Wauthier, V. Cayol, F. Kervyn, N. d'Oreye: THE JANUARY 2002 ERUPTION OF NYIRAGONGO VOLCANO (DRC) CAPTURED BY INSAR. Abstract for 2009 IEEE International Geoscience & Remote Sensing Symposium, July 13-17 2009, Cape Town, Africa
  • van Overbeke Anne-Catherine, Smets Benoît, Wauthier Christelle, d’Oreye Nicolas, Tedesco Dario, Kies Antoine, Mitangala Prudence, Bagalwa Montfort, Yalire Mathieu, Lukaya François, Kavotha Deogratias, Osodundu Etoy, Durieux Jacques, Kervyn François: THE IMPORTANCE OF REMOTE SENSING IN THE MONITORING OF VOLCANIC ACTIVITY IN THE GOMA REGION (DR OF CONGO): EXPERIENCE FROM THE GORISK PROJECT. Abstract for 2009 IEEE International Geoscience & Remote Sensing Symposium, July 13-17 2009, Cape Town, Africa
  • N. d’Oreye, G. Celli: Automatic InSAR systematic processing and web based tool for efficient data mining: application to volcano monitoring in Africa.Proc. of 5th ESA Fringe2009 workshop, ESA-ESRIN, Frascati, Italie, 30 November-4 December 2009.
  • N. d’Oreye, P. Gonzalez, A. Shuler, L. Bagalwa, G. Ekstöm, D. Kavotha, F. Kervyn, F. Lukaya, E. Osodundu, A. Oth, C. Wauthier: Was the February 2008 Bukavu Seismic sequence associated with magma intrusion ? Proc. of 5th ESA Fringe2009 workshop, ESA-ESRIN, Frascati, Italie, 30 November-4 December 2009.
  • C. Wauthier, V. Cayol, F. Kervyn and N. d’Oreye: The January 2002 eruption of Nyiragongo volcano (DRC) captured by InSAR. Proc. of 5th ESA Fringe2009 workshop, ESA-ESRIN, Frascati, Italie, 30 November-4 December 2009.
  • Valerie Cayol, Nicolas d'Oreye, François Kervyn, C. Wauthier and the GVO team: InSAR displacements associated to the November 2006 Nyamulagira eruption. Proc. of 5th ESA Fringe2009 workshop, ESA-ESRIN, Frascati, Italie, 30 November-4 December 2009.
  • A.M. Oyen , C. Wauthier, N. d’Oreye, R.F. Hanssen: The 2007 rifting event in Northern Tanzania studied by C and L-band interferometry . Proc. 95è Journées Lux. De Géodyn., Luxembourg, 9-11 Novembre 2009.
  • N. d’Oreye, P. Gonzalez, A. Shuler, L. Bagalwa, G. Ekstöm, D. Kavotha, F. Kervyn, F. Lukaya, E. Osodundu, A. Oth, C. Wauthier: Was the February 2008 Bukavu Seismic sequence associated with magma intrusion ? Proc. 95è Journées Lux. De Géodyn., Luxembourg, 9-11 Novembre 2009.
Project Website:

Figure: View on the town of Goma