European Space Agency (ESA) satellites have captured a stunning visual of how last week's powerful earthquakes significantly altered Venezuela's landscape. Using advanced radar technology, the Sentinel-1 satellites have created an image revealing ground deformation caused by the seismic events.
These aren't your typical photos. Instead, the Sentinel-1 satellites "illuminate" the Earth's surface with radar and measure the signal's return time. By comparing data from before and after the earthquakes, scientists can detect even tiny ground shifts invisible to the naked eye.
The image was generated by comparing radar data from June 18, a week before the quakes, with data from June 25, the day after a pair of magnitude 7.2 and 7.5 earthquakes struck. This comparison technique, known as interferometry, creates a map showing how the ground deformed. The colorful bands on the map indicate shifts in distance between the satellite and the ground, with more color cycles signifying greater displacement.
The most intense deformation, estimated at around 30 centimeters (12 inches), is concentrated in the north, correlating with the earthquake epicenters and following the San Sebastián fault system. While the interferogram shows the extent of the change, it doesn't specify the direction – whether the ground moved up, down, or sideways. Determining that requires further analysis and on-the-ground surveys, which are challenging amidst the ongoing humanitarian crisis and damage to infrastructure.
Space agencies globally, including NASA with its Disaster Response Coordination System, are collaborating to share crucial data that can aid Venezuela's recovery efforts following the devastating earthquakes.
