The risk is very high in other states of the country. Earthquakes happen all the time. The important thing to do is to monitor, identify and catalogue their locations so that we can improve on future forecasts in time and space. To do these, we need to upgrade the infrastructure of the current seismic network system to a state-of-the-art digital seismic network with real-time telemetry capabilities. We need to invest in the training of engineers, technologists, students, scientists and researchers to participate in earth science research that would improve our understanding of Nigerian and West African geophysics and tectonics. Research has a crucial societal value evident in earthquake hazard readiness and mitigation.
The recent report of earth movement in Kaduna, has, indeed, brought a renewed attention to earthquake phenomenon as a potent natural hazard in Nigeria. The most recent earthquake detected and recorded by local digital sensors (seismometers) occurred in the Republic of Benin and was felt in a few states in the South-West. This is one in a growing sequence of earthquakes felt in other cities in Nigeria. With the inception of the seismometer networks in Nigeria since 2006, the monitoring and detection of earthquakes has greatly improved, although there is more room for improvement. Nigeria is among the three countries in West Africa with a seismic network, the others being Cameroon and Ghana. With these sensors, seismologists can locate where an earthquake occurred, its magnitude (how destructive it is) and build a catalogue that includes useful parameters that can help further research into the frequency and causes of the earthquake.
Two key issues, however, plague the current state of our readiness for earthquake hazard assessment and mitigation in Nigeria. The first is a weak early warning detection system that is built around a sophisticated real-time digital seismic network. The second is the absence of a continuously updated and regional earthquake catalogue that should help to assess the risk of different states in the country and neighbouring countries.
Although Nigeria has the largest number of seismic stations on her national network, Ghana is the leader in digital seismic network observatory. Two key components distinguish Ghana’s seismic observatory from Nigeria’s. The first is the quality of the hardware and software infrastructure. The second, equally as important, is a real-time telemetry system that can relay data to any location regionally and globally. So, there are several areas Nigeria needs to improve to manage earthquakes.
It is clear that an investment in upgrading seismic monitoring infrastructure should be of priority. What is even more pressing is the renewed attention on funding and support for earthquake research through earth science and solid earth geophysical research. Unfortunately, very little research is being conducted or supported both locally and internationally on key geophysical issues that relate to Nigeria. A few researchers who worked on the key topics in the 1940s are nearing retirement, with little or no efforts made to educate and mentor new scientists to power the next generation of research. This is discouraging considering that data point to a growing need for personnel to provide expertise in managing geophysical infrastructure, training students and conducting researches that are useful to informing local policymakers. • Dr. Adepelumi Abraham (Department of Geology, Obafemi Awolowo University)
First, we need to understand that earthquakes are caused by disturbances within the earth crust. A disturbance could be located in a particular state. It could also cut across two or more states. If more states are involved in the disturbance that led to the Kaduna earth tremor, those states are at risk.
What we need to ask is – what is the extent of the disturbance? To what extent are the bedrocks distorted? If there is a state of nonconformity in the rock setting, there is the likelihood that there would be an internal disturbance. There could also be a disturbance in the mantle of the earth. This could cause a crack that could lead to a readjustment.
Africa is a stable continent compared to other places. For the past 60 million years, Africa has been very stable unlike the mobile zone of the globe which includes Japan and Australia. This is because the rock on which Africa is located is not fragile. But for its stability, Africa would have been experiencing tremors everywhere by now.
The only challenge is if there are mining activities that are not properly monitored and regulated, there could be internal disturbances. If there are, more states would be prone to tremors and other disturbances. • Uche Jude (An expert in Physical Geography)
Other states might be at risk. We have had a series of incidents. What we need to do is to properly monitor the changes in the geophysical composition of the country. We need to constantly update the data we have because things are changing very fast.
Also, we need robust earthquake monitoring centres which can regularly give advice to policymakers on critical actions that should be taken and areas that need government attention. Experts should be encouraged to carry out detailed and regular geological survey of Nigeria. We have experts that can carry out such projects but they need to be encouraged.
We may have to instal earthquake monitoring units in strategic positions in the country. Experts need to survey the country and advise the country on where we should instal such facilities. ) • Ejiro Erharhaghen (A geophysicist)
One of the major challenges facing us as a country is that we do not have the technical capacity to manage natural disasters. Every country should put in place early signal measures. That is what is being done all over the world.
But in Nigeria, we do not have the required equipment to monitor signals. Apart from equipment, we do not have the technical manpower to manage natural disasters.
Flood has become a major challenge in the country. But how prepared are we to deal with the problem? Do we have the technical capacity to respond to the problem? At both national and state levels, response is poor. Even when we know that there is a likelihood of flood resulting from excessive rainfall, we do not have the capacity to prevent or manage it when it occurs. And that puts many lives and properties at risk. Hence, we witness so much damage in terms of displacement and destruction of properties.
We need to prepare for some of these things. There was a tremor in Kaduna State recently. Who knows what would happen next? Who knows where it would happen next? Those are critical questions we need to respond to as a country. But we need equipment and expertise to properly respond to them. • Adedeji Adeleye (Executive Director, Independent Advocacy Project)
To reduce the risk of tremor in the country, we need to enhance the regulation of mining activities. Areas where mining take place need to be properly monitored. Earthquakes and tremors are consequences of movements within the earth crust. Such movements could be horizontal or vertical. The deeper the movement, the more intense the quake becomes. What happened in Kaduna was a movement on the shallow surface of the earth. That is why the strength was not much.
Every country of the world is at the risk of earthquake, which could happen at any time. But you would experience these disasters in places where you have much mining activities. It is like when you create a hole underneath the earth. The uppermost part would eventually sink.
If what happened in Kaduna was due to mining activities, we need to control and coordinate mining. Mining activities are causing a lot of environmental degradation in the country. We have to control them. We can also enhance our monitoring centres to be able to keep records of earth tremors. We need to deploy technological equipment that can pick earth vibrations afar. This is what is done all over the world. This is why the United States would know when Russia detonates a bomb. We need to enhance our capability to pick earth tremor so that we can monitor areas that are prone to such. • Prof. Rafiu Bale (Department of Geology and Mineral Sciences, University of Ilorin)