Nearly a month after the two earthquakes of June 24 left at least 4,930 people dead, 17,854 displaced and thousands more missing, Venezuela is still trying to understand the full extent of the disaster. There is no centralized damage assessment, no authoritative accounting of destroyed buildings and no definitive picture of what was lost. 

Reconstruction, however, cannot wait for perfect data. Families need housing and infrastructure must be restored, yet the decisions made today will shape our cities for decades. Engineers, geologists, and other specialists are converging on why the earthquakes proved so destructive, where the limits of current knowledge lie, and which popular explanations are unsupported by the available evidence. 

Why the earthquakes were so destructive 

The physical characteristics of the June 24 earthquakes are relatively well understood. Instead of enduring a single shock, many structures were hit by a second, more intense earthquake before they had recovered from the first. Structural engineer and Cazadores de Fake News director Adrián González explains that a structure shaken hard enough to crack without collapsing loses stiffness and consumes part of the reserve capacity built into its design. 

Thirty-nine seconds later, the second rupture strikes what is, in effect, a different building: one already weakened by the first earthquake. As González puts it, “the combined effect isn’t equivalent to simply adding the two earthquakes together.”

The aftermath of the disaster quickly generated competing explanations about construction quality, engineering standards and government responsibility. Yet the damage rarely speaks for itself. To draw meaningful lessons from the disaster, the evidence has to be read in context.

Another factor was resonance. Esteban Tenreiro, a structural engineer, has explained in multiple interviews that each structure has a natural swaying period, the rhythm at which it tends to sway. As with sound, when seismic motion approaches that rhythm, the building’s movement can be amplified. Yet, the earthquake itself is only part of the story. Geologist Luiraima Salazar explains that an earthquake’s impact depends not only on its magnitude but also on the ground through which its waves travel.

Soft sediments, like those underlying much of La Guaira, can amplify ground motion, prolong shaking and, in saturated soils, trigger settlement or liquefaction. González explains the behavior of this type of soil using the metaphor of gelatin on top of a plate. Shake the plate once and the gelatin continues moving in broad, slow waves after the plate has stopped. 

Much of urban La Guaira sits on alluvial deposits that amplified and prolonged the motion, meaning buildings experienced the second earthquake while the ground beneath them was still reverberating from the first.

What the rubble can (and can’t) tell us

The aftermath of the disaster quickly generated competing explanations about construction quality, engineering standards and government responsibility. Yet the damage rarely speaks for itself. To draw meaningful lessons from the disaster, the evidence has to be read in context.

González distinguishes between two broad explanations for structural failure: insufficient capacity and excessive demand. A building may have had insufficient capacity because of poor materials, deficient detailing, or construction that failed to comply with the applicable code. On the other hand, a building that is code-compliant may have been subjected to forces beyond what was anticipated, like two major earthquakes within a minute. 

The same caution applies when comparing buildings of different ages. “Earthquake-resistant” has not meant the same thing throughout Venezuela’s history because seismic regulations have evolved considerably. Before 1967, seismic forces were barely incorporated into structural design. Throughout the 20th century, regulations became increasingly sophisticated and, with the 2001 code, engineers began calculating seismic forces according to a building’s own vibration period. Venezuela’s seismic regulations are relatively strict by international standards, according to Tenreiro.

Catastrophic earthquakes, however, do not follow statistical schedules, and many Venezuelan buildings have remained in use far longer than the service life assumed when they were designed.

An earthquake-resistant building is not designed to emerge unscathed from every earthquake. It is designed to behave predictably under the “design earthquake” established by the applicable code. Those standards are based on probability: engineers plan for a level of shaking that has a specified likelihood of being exceeded during a building’s expected useful life. Catastrophic earthquakes, however, do not follow statistical schedules, and many Venezuelan buildings have remained in use far longer than the service life assumed when they were designed.

Structural elements may crack or deform, but the principal goal is to prevent collapse and protect occupants. Essential facilities such as hospitals, schools and fire stations are held to stricter performance requirements because they are expected to remain operational after a disaster.

Yet even compliance with those standards cannot fully explain what happened on June 24. Civil engineer Luken Quintana, who works with the damage-documentation initiative SismoAyuda, notes that conventional seismic codes are not designed around two major earthquakes occurring 39 seconds apart. That distinction is not a universal explanation for collapse, nor does it excuse poor construction. It does suggest that code compliance alone cannot explain why a particular building failed.

Venezuela still lacks a centralized assessment of structural damage, meaning every broader diagnosis remains preliminary. Even so, the reports compiled through SismoAyuda are beginning to reveal the first patterns. By July 12, SismoAyuda had received reports on 2,366 buildings. Preliminary remote assessments classified 296 buildings as unsafe or collapsed and another 592 as requiring restricted entry, although the initiative emphasizes that its voluntary database cannot be treated as an official census.

Among damaged buildings with a known construction date, 332 were built before 1970. This is more than all buildings constructed after 1970 combined. The largest single category consisted of one- to three-story buildings, with 274 reported structures requiring restricted entry or classified as unsafe or collapsed. The finding surprised engineers because low-rise buildings generally experience lower seismic demands. For now, there is no accepted explanation.

That uncertainty is not a weakness of the investigation but part of the process itself. Engineers do not draw conclusions from isolated examples. Instead, they look for patterns. A single collapse may reflect poor construction, unfavorable soil conditions, or exceptionally strong shaking. Repeated failures involving the same structural system, materials or design across multiple locations provide much stronger evidence of a systemic problem.

The task now is to examine failures building by building. Those investigations should determine which standards governed each structure, whether appropriate soil studies were conducted, whether construction matched the approved plans and whether authorities properly reviewed and inspected the work.

The same principle applies to some of the most widely debated aspects of the disaster. In the days following the earthquake, the performance of individual buildings from the Gran Misión Vivienda Venezuela became part of a broader political argument about the quality of the buildings. Quintana argues that there’s simply not enough evidence to draw broader conclusions about the housing program.

Determining why a building fails requires a structural pathology study rather than comparisons between isolated buildings. Moreover, just because a building remains upright doesn’t mean it is safe: a structure with material or design deficiencies may survive if the particular characteristics of the ground motion do not push it to its limit, while remaining vulnerable to a future earthquake.

Similar caution applies to viral images of expanded polystyrene found in the rubble. Quintana emphasizes that just because a material is present, it doesn’t mean that it contributed to the collapse, or that it was used incorrectly. Buildings fail as structural systems, not as isolated construction materials. 

The task now is to examine failures building by building. Those investigations should determine which standards governed each structure, whether appropriate soil studies were conducted, whether construction matched the approved plans and whether authorities properly reviewed and inspected the work. Only then will investigators be able to establish responsibility and identify the errors that must not be repeated.

The economic cost of the earthquakes will eventually be estimated. Continued investigations should produce a clearer picture of how many buildings collapsed and why. The social and human damage will be far harder to measure. Families have been displaced, communities have been disrupted, and lives have been permanently altered. Those consequences will shape the country for years.

The country already possesses much of the technical knowledge needed to rebuild more safely. Now, the challenge is having institutions capable of putting that knowledge into practice.