Seismologists have provided a detailed analysis of the recent 7.5 magnitude earthquake that struck Venezuela, categorising it as a 'doublet' event. This type of seismic sequence involves two earthquakes of similar magnitude that are causally linked but distinct in their seismological characteristics. The main tremor was preceded by a 7.2 magnitude foreshock, with both events occurring mere kilometres apart within a 39-second interval.
Dr Raffaele De Risi, an Associate Professor in Civil Engineering at the University of Bristol, stated that while the situation is a human tragedy, the seismic activity broadly aligns with scientific expectations for an event of its size, depth, and location. The earthquakes originated from shallow crustal depths, with the 7.2 magnitude event at approximately 22 km and the 7.5 magnitude quake at around 10 km. Both were strike-slip faulting mechanisms, which involves horizontal motion, consistent with the geological characteristics of the region.
The tremors occurred along the extensive transform boundary between the Caribbean and South American plates, specifically within the Boconó–Morón–El Pilar fault system. This complex network of right-lateral strike-slip faults spans roughly 1,300 km across northern Venezuela. The proximity of the epicentres and the short time gap between the two quakes suggest that the first rupture likely triggered the second, a phenomenon where static stress transfer and dynamic waves push an already stressed fault segment past its breaking point. While uncommon, such 'doublet' events are not unprecedented, with the 2023 Kahramanmaraş sequence in Turkey serving as a recent comparison.
Strong shaking was reported in areas such as Guaira, where significant damage has been localised, and in the capital, Caracas, located approximately 170 km to the east. Experts anticipate widespread ground failure, including landslides in the mountainous terrain and liquefaction in saturated, loose sediments found in coastal plains and river valleys. Caracas itself is particularly vulnerable due to its underlying sediments, which can amplify seismic waves and intensify earthquake damage even at a considerable distance from the epicentre.
Despite the scientific understanding of these events, experts firmly state that predicting the exact time, location, and magnitude of an earthquake in advance remains impossible. No current scientific method allows for such precise forecasts, and any claims to the contrary should be met with scepticism. However, long-term probabilistic hazard assessments are feasible, enabling scientists to identify active fault systems capable of generating large earthquakes and to map potential risks. The true extent of the damage and ground failure will be confirmed through field reconnaissance and satellite imagery in the coming days.