Week 3- Earthquakes

For this week's blog, I'll be discussing Ghana's earthquakes and what is done to prevent/prepare for hazards. There are real-time sites you can see to be alert if there were any earthquakes.

 


Ghana has had damaging earthquakes as far back as 1636 as mentioned. Ghana is not in an earthquake zone but earthquakes do occur. Also, the southern part of the country is seismically active. A study on the microseismic activity in southern Ghana shows that the seismic activity is linked with active faulting between the east-west trending Coastal boundary fault and a northeast-southwest trending Akwapim fault zone.

Epicenter map with the computed (formula (1)) intensity isolines based on the data of the earthquake catalogue. Plotted are the isolines starting with intensity 4.0 in steps of one degree. The depth H for the quake of 1939 is 18 km. For unknown focal depths, H = 8 km was estimated. a = 0.001 km À1 was fixed.



It has been recorded that the worst earthquake that has occurred in Ghana was in 1939 in Accra which is located in the Greater Accra Region. This massive earthquake killed 17 people and caused lots of property damage. The last earthquake and more recent one was on December 12, 2022, which was a 4.0 in magnitude. It happened three times in the period of five times. 

Accra experiences moderate earth tremor of magnitude 4.0 - Graphic Online



What is done to prevent or help during these hazards? The National Disaster Management Organization has come out with a building guide to assist in the mitigation effort of earthquake disasters and floods in the country. Ghana, through the efforts of UNESCO, has received a set of equipment to support its earthquake preparedness efforts.


Comments

Post a Comment

Popular posts from this blog

Week 5- Volcanos

Image
 Ghana is located in West Africa. As for volcanos directly coming from Ghana, there are not any. Not to say that there aren't any in Africa because there sure are volcanoes in Africa. 🌋  What Ghana does have are volcanic rocks in the southeastern part of Ghana .  To be more exact  The Buem volcanic rocks of Ghana  form part of the Dahomeyide Chain on the southeastern flank of the West African Craton . (It is stated by science direct  )  The principal sedimentary rocks associated with the Buem volcanic rocks in Ghana are shales and sandstones. The rocks do vary but are generally aphanitic, ophitic, and massive. It is known that Ghana has plenty of volcanic belts from north to south .
Read more

Week 13: Coastal Hazards

Image
Ghana is affected by coastal erosion. Which is led by human activities that amplify the rise in water levels linked to global warming are largely responsible for this. There are villages in Ghana that are becoming islands.  Ghana’s economic success over the last decade has come at a price, particularly for the country’s coastline .  Unregulated human activities have greatly accelerated the problem of coastal erosion − a natural ongoing process by which coastlines adapt to varying sea levels, the energy levels of the tides and currents, sediment supply, and the existing topography over hundreds of years.  Sand mining for dams started the rot followed by the construction of deep sea ports. It is stated that 37% of the country's coastal land was lost to erosion and flooding between 2005 and 2017. With that being said  heavy waves and floods have eaten into the shoreline have caused the percentage to go up. 
Read more