Introduction

 

The Nicaraguan Institute of Territorial Studies (INETER) continues with the Annual Catalogue, "Earthquakes and Volcanoes of Nicaragua, 2004" the tradition to inform in summarized form on the seismic and volcanic activity, the geological phenomena in Nicaragua, the development of the monitoring network and on our research projects. The content is based on the monthly bulletins that the Geophysical Department of INETER publishes regularly.

 

The Geophysical Department of INETER has the principal responsibility to monitor the seismic, volcanic and geologic phenomena in Nicaragua, operates networks of seismic and geophysical stations and performs the volcanic surveillance. Furthermore, it executes scientific studies and develops a Geographical Information System (GIS) on the dangerous geological phenomena. Geophysical Department includes 1) Seismology Section (with Electronic Lab); 2) Volcanology Section; 3) Section for Geology Applied to Disaster Prevention; 4) GIS Unit on “Geo-Risks”.

 

The most important natural events observed by the Geophysical Department in 2004 and reported in this catalogue occurred in January and February (seismic activity of the Cerro Negro volcano), May (lahar at the Concepcion volcano), October (seismic event with ML=6.8 in front off El Astillero), November (seismicity in the Momotombo volcano) and December (magnitude 9.0 earthquake generates disastrous tsunami in Indonesia).

 

Included is information about other seismic events, about swarm seismicity and on the seismic events felt by the population, mainly in the Pacific Region of Nicaragua.

 

In 2004, INETER intensified the seismic and volcanic surveillance of the active volcanoes in Nicaragua. 101 field visits to the active crater areas were made; monitoring with Web cams and meteorological stations was improved.

 

During 2004, a total of 84 studies, carried out in Managua by private geologists, were supervised and the results confirmed. These studies are required by local regulations for the permission of construction projects.

 

Geophysical Department worked in 2004 in 14 research and development projects which are resumed shortly in the catalogue. Some projects have a strong social component. E.g. in there were investigated since 2003 the natural hazards in 70 sites located mainly in rural areas throughout Nicaragua, where new houses will be built. Up to now, these studies made sure for more than 7,000 families that their new homes will be build in safe areas.

 

The fast development of the Geographical Information System (GIS) on Georiscs in Nicaragua and Central America continued in 2004. The system is already functional and makes much more efficient the elaboration of hazard maps, and the evaluation of risks and emergency situations due natural phenomena. Data from INETERīs monitoring and early warning systems are included, in real time, in the GIS data base and are presented at INETERīs Web site.

 

Workshops and meetings for technical training, scientific exchange and information to the population about the results of our work played an important role in this year.

- On February 2 to 9, a workshop on Hazard Mapping with emphasis on Volcanic Hazards and Landslides was imparted at INETER. The event supported by COSUDE and INETER was imparted by scientists from the Institute of Geophysics, UNAM/Mexico.

- On March 12 to 15, the workshop "Reduction of the Volcanic Risk in Nicaragua and Central America through Local Application of Remote Sensing and of the Improvement of the Communication of the Risk." was carried out in Managua, in cooperation with Kingīs College, London.  

- From May 8 to 13, five specialists of the Geophysical Department of INETER participated in an International Workshop on Seismic Networks that was carried out in the town Volcano, in the Northwestern part of Panama. The event was financed by NORAD and CEPREDENAC.

- In the month of September, as a part of collaboration with UNAM, Mexico, maps of volcano hazards of Masaya volcano were handed over to representatives of the Central Government, to Municipal Authorities in the Masaya area, to SINAPRED, Civil Defense and journalists.

- In December, the new geological maps of Somoto area were presented to the local authorities of this municipality. These maps were elaborated together with the Czech Geological Survey.

 

2004 was one of the most successful years in the development of the Geophysical Department of INETER what is truly reflected in the present annual catalogue.