Earthquake is, of course, a sudden, usually violent trembling of Planet Earth that is volcanic or tectonic in origin, relating to deformation of the Earth’s crust. The majority of severe Earthquakes results from fractures usually along existing faults in underlying rock strata that are subjected to strong strains.
The shearing movements may then extend to the Earth’s surface. The Richter scale was developed in the 1930s, to be applied in determining and expressing the magnitude of Earthquakes this side of Hades! For the technically-inclined who don’t mind being blinded with Science, the scale –named after the American Seismologist Charles R Richter – a logarithmic scale for expressing the magnitude of a seismic disturbance, like Earthquakes, in terms of the energy dissipated in that disturbance.
Thus, for example, a magnitude-3 on the scale is equal to 2 gigajoules; magnitude- 5 is 2,000 gigajoules; and magnitude-7 on the scale equals 2 million gigajoules… ‘Each higher number on the Richter scale represents a tenfold increase in the energy measured in ground motion.’ Get that? I don’t!
The ‘1.5’ magnitude indicates the smallest Earthquake that can be ‘felt,’ while a ‘4.5’ reading is the Earthquake causing slight damage… the 8.5 reading indicates a very devastating Earthquake – perhaps the Mother of Earthquakes in a given area, at a given time! [Never mind that the Richter scale was succeeded in the 1970s by the ‘Moment Magnitude’ scale, currently used by the US Geological Survey to estimate magnitudes for all modern large earthquakes]!
Back to Richter…Where does that leave the ‘5.9’ magnitude Earthquake which suddenly and violently shook the Kagera Region in north-west Tanzania, as well as parts of the neighbouring countries of Burundi, the Democratic Republic of Congo, Kenya, Rwanda and Uganda – listed here strictly in alphabetical order, NOT according to the resulting impact. Earthquakes have been with us from time immemorial.
But, historians tell us that, because of their phenomenal destructive power, Earthquakes have attracted attention from the earliest times. However, studies to determine their magnitude date back two centuries, while a worldwide network of Earthquake recording stations was developed only in the last century.
But, no matter…! As already noted herein above, the recent Earthquake in this part of the world – Kagera Region in particular, as that was apparently where the ’Quake was most destructive –measured 5.9 on the Richter scale.
The damage resulting from that disaster has been assessed at 19 people killed and 253 injured in Tanzania. Four people were killed in Kamuli, and seven injured in the Rakai District of Uganda. That’s to say nothing of domestic livestock and wildlife impacted, as well as buildings razed to the ground or partially destroyed; people rendered homeless, as well as considerable damage to assorted economic and social infrastructure, including hospitals, schools, utilities, communications.
There’ve, of course, been more tragically-destructive Earthquakes in different parts of the world. A few examples…? Well, there were the May 20, Year-526AD Earthquake in Antioch, Syria, that claimed 250,000 lives; the January 24, 1556 Earthquake in Shaanxi, China, with 830,000 deaths; and the October 11, 1737 Earthquake in Calcutta, India: 300,000 deaths.
But, there was as yet no way to determine the magnitude of those tectonic maladies. A relatively ‘recent’ notable example that was measured post-the Richter scale adoption was the February 29, 1960 Earthquake in Agadir, Morocco (5.8 on the Richter), which killed 12,000 people!
By comparison, the ‘Kagera-Tanzania’ Earthquake, which registered 5.9 on the Richter – moreor- less like its ‘Richter-5.8’ Morocco cousin – resulted in 23 deaths only… pardon the unintended callousness here!
Other recent examples are the July 28, 1976 Earthquake in Tangshan, China (8.2 magnitude; 242,000 deaths)! And, at the other end of casualties spectrum was the March 27, 1964 Earthquake in Alaska, whose rather alarming 8.4 magnitude nonetheless resulted in only (no callousness intended here) 131 deaths!
So, does population size/ density in a ’Quake-hit area factor in the equation? Well, don’t answer that in a hurry…! Take, for instance, the 7.5-magnitude ’Quake that hit Southern California on June 28, 1992 resulting in only a single death out of a 22.68 million-strong population!
Then consider the lesser-magnitude ‘Kagera’ Earthquake (5.9), which claimed 19 lives out of a 2.458m population… And the December 7, 1988 Spitak Earthquake in Armenia (6.8-‘surface wave magnitude’) killed more than 25,000 people, injured 30,000 – and left 500,000 homeless out of a population of 3.5m. Shows you that earthquakes and the sisters of fate work most mysteriously, don’t they? Don’t they ...I ask you...Tears!
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