How is an earthquake measured? Discover the science behind the measurement and reflections of the earthquake in Venezuela
Assessing the strength of an earthquake presents significant challenges, as these events occur suddenly and can impact several regions of the planet simultaneously.
An earthquake occurs when the Earth’s crust moves suddenly, releasing energy through seismic waves and tremors that can be perceived by people, buildings and infrastructure.
Seismic waves and other elements linked to ground movement are crucial to determining the magnitude of an earthquake, measured on a scale that reaches the number 10 and is the most adopted to describe these phenomena.
The intensity of an earthquake refers to its strength in a given location, quantified by a scale that uses Roman numerals to categorize the effects based on the damage observed and observations made by the population.
Understand how the strength of a tremor is calculated with the moment scale
To determine the size and energy released by earthquakes, scientists predominantly use the “moment magnitude scale”, considered more accurate than the old “Richter scale”, according to information from the United States Geological Survey. Choosing this more accurate methodology is essential, especially in large-scale events like the one recorded in Venezuela, where an exact understanding of the energy released is vital to assess the impacts.
This moment magnitude scale is based on the “seismic moment” of the tremor, which encompasses the displacement of the Earth’s crust, the extension of the area along the geological fault and the resistance necessary to overcome friction at the site, in addition to the seismic waves generated by the movement.
Consequently, the magnitude of the moment will be greater when there is greater friction and a more extensive displacement over a greater distance.
Seismographs are the instruments used to record seismic waves; they operate with a pendulum connected to a spring that moves in response to ground shaking, producing a graphic record known as a seismogram.
Magnitude classification is carried out in up to ten numerical levels, and each increase of a whole number on the scale means a release of energy 32 times greater, highlighting the exponential power of these phenomena.
Leia Também
Messi reaches 19 goals in FIFA World Cups with great free kick for Argentina in clash with Jordan
Cristiano Ronaldo shines beyond the pitch at the 2026 World Cup with business empire and family luxury
At 41, Cristiano Ronaldo reaffirms his historic legacy and prepares to shine in the 2026 World Cup
Analysis of local impacts: the Modified Mercalli scale
The intensity of an earthquake is evaluated using the “Modified Mercalli Scale” of intensity, also known by the acronym MMI.
This tool measures the power of the earthquake at specific points around the epicenter – the area on the Earth’s surface located directly above the underground point of origin of the earthquake.
The MMI scale uses Roman numerals to define the intensity of a tremor, based on assessments of structural damage and reports from observers. In Venezuela, the earthquake raised the number of deaths to 188 and resulted in the destruction or damage to 250 buildings.
Progress in the count of victims and damage after the earthquake in Venezuela
The two intense earthquakes that hit Venezuela on Wednesday (24) caused 188 deaths and left 1,520 injured, with the expectation that these numbers could grow due to the vast extent of the devastation.
Venezuelan cities like Caracas saw entire buildings and homes collapse. Rescue teams were working actively this Thursday morning (25) searching for survivors among the rubble.
The second tremor, with a magnitude of 7.5, represents the most powerful tremor to hit Venezuela in more than a century. The colossal force of this event, measured by the moment magnitude scale, underlines the enormous energy released, which can be up to 32 times greater with each increment on the scale.
In response to the calamity, Venezuelan President Delcy Rodríguez declared a state of emergency in the country. Itamaraty reported that there are no records of affected Brazilian citizens.
Brazil, the United States and European countries mobilized and sent rescue teams to assist the nation. The tremor was also noticed in locations in northern Brazil, including Manaus and Belém.
