NISAR finds twin Venezuela quakes shifted ground by nearly two feet

Washington,UPDATED: Jul 27, 2026 00:00 IST

An analysis of data from the NASA-ISRO Synthetic Aperture Radar (NISAR) satellite has found that the twin earthquakes that struck northern Venezuela on June 24 shifted the ground by almost two feet in some places, adding to the devastation in Caracas and La Guaira. The study used satellite images taken before and after the quakes to track changes in the terrain.

The first earthquake measured magnitude 7.2 and was followed 39 seconds later by a magnitude 7.5 mainshock. The disaster killed more than 5,000 people and injured 16,700, while causing large-scale damage in Caracas and La Guaira. The states of Trujillo, Yaracuy, Carabobo, Aragua and Miranda were also affected.

Researchers examined images captured by NISAR on June 13 and 18 before the earthquake, and on June 25 and 30 after it. Scientists used a technique called InSAR, which compares data from repeat satellite passes to detect small changes in the distance between the satellite and the ground, NASA said in a statement earlier this month. This was the first time the NISAR urgent response system was used to map surface displacement from a large earthquake.

The fault is part of a network of fractures along the boundary between the Caribbean plate to the north and the South American plate to the south. Scientists said faults along this boundary, including the San Sebastian fault system, where the quakes likely occurred, and possibly part of the Bocono system, have long been building strain. The fault rupture moved offshore towards the east and then back onshore near the international airport north of Caracas. Just south of this section, displacement was much greater than elsewhere, reaching as much as 60 centimetres, or 24 inches. “These are reasons why the damage in Caracas and La Guaira was so extreme,” said Eric Fielding, a geophysicist at NASA's Jet Propulsion Laboratory. “InSAR tells us a lot about what happened during this earthquake,” he said.

According to NASA, NISAR views Earth at an angle of about 40 degrees from straight down, allowing it to capture a mix of horizontal and vertical displacement. Using the NISAR data, the US Geological Survey refined its fault-slip model, or finite fault model, to better understand how the fault slipped at depth, including along the rupture's eastern section. “That is extremely helpful for the people who need to understand why the damage was so severe in that area,” Fielding said. NASA said the displacement maps were provided through NISAR's Urgent Response system, which can deliver data within 12 to 24 hours to support disaster response, although the rapid maps are preliminary until they are reprocessed with precise orbit information, usually within a day or two. The analysis showed how the satellite data helped explain the scale of ground movement and the severe damage caused by the Venezuela earthquakes.

With PTI Inputs

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