The Botswana Geoscience Institute operates a network of 21 seismic monitoring stations located throughout Botswana at an approximate spacing of 200 km. These stations record any earth tremors and are telemetered to relay the information at close to real-time to BGI data centre in Lobatse for processing. Products from this work include seismicity maps used by the public to determine the earthquake vulnerability of different areas before putting up structures and buildings.
Seismology is a scientific discipline that is concerned the study of earthquakes and the propagation of seismic waves within the earth. It provides information about the composition and state of the planet’s interior.
BGI has seismicity monitoring as its integral function. Botswana experienced its largest earthquake of the magnitude 6.5 in April 3, 2017 and its impact was felt across the country.
Whilst there is generally, a low probability that another big seismic event will occur in Botswana in the near future it is important to recognize the potential for such catastrophic impacts in urban centers and major villages across the country, and to apply appropriate mitigation measures.
Earthquakes in urban areas are more dangerous because of the density of the infrastructure. The rapid growth in the number of people living in cities, towns and urbanized village landscapes is increasing in Botswana, and this is paralleled by a corresponding proportional increase of susceptibility to natural disasters such as earthquakes.
Therefore, rapid urbanization of Botswana necessitates the need for detailed seismic microzonation to predict the nature of impacts should a seismic event occur. The initiative will also go a long way in establishing seismic building codes and increase building integrity in order to ensure the future safety of communities. Seismic codes are intended to protect people inside buildings by preventing collapse and allowing safe evacuation. Structures built according to such local codes should resist minor earthquakes undamaged, resist moderate earthquakes without significant structural damage, and resist severe earthquakes without collapse.
The BGI has therefore embarked on a project to set-up a seismological research centre to give full focus to researches relating to earthquakes and their associated impacts.