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European space The agency released a satellite image showing the disturbances left behind A pair of earthquakes Which Venezuela shook Last week.
The image was created using observations from the Sentinel-1 satellite, which is part of Europe’s Copernicus programme. These satellites do not take conventional images; Instead, they use their radar to “illuminate” the Earth’s surface and record the time it takes for the signal to return to the sensor. By comparing two measurements of the same location taken on different dates, scientists can determine whether the Earth has moved, even when that shift is too small to be seen with the naked eye.
To create the map, scientists compared an observation taken on June 18 — one week before the quakes occurred — with another observation taken on June 25, the day after the quakes. A pair of earthquakes measuring 7.2 and 7.5 respectively. This comparison allowed them to construct what is known as an interferogram that reveals how much the Earth was distorted after the event.
What stands out in the map are the repeating colored bands that form horizontal rows in the north, ESA explains. Each complete repetition of the sequence – blue, green, yellow, red and blue again – represents a constant increase in change in the distance between the satellite and Earth. The more complete cycles that appear between one area and another, the greater the cumulative ground displacement.
The banding pattern observed in the northern part of the map corresponds to the area at the epicenter of the earthquakes, which is also where the main deformation occurred. These ranges roughly follow the path of the San Sebastian Fault System, one of the major tectonic structures in northern Venezuela. The European Space Agency estimates that displacement in the area was on the order of 30 cm (12 in).
