Northern Venezuela is no stranger to large, damaging earthquakes. But the pair that tore through the region on Wednesday ranks as a rare catastrophe — a one-two punch representing one of the most powerful tectonic events to strike there in the past century.

委内瑞拉北部地区发生破坏性大地震并不罕见。但周三袭击该地区的两次强震堪称罕见的灾难——这场连环重击是过去一个世纪以来袭击该地区最强烈的地质构造事件之一。

At 6:04 p.m. local time, a magnitude 7.2 temblor struck to the west of the capital city of Caracas; this was followed just 39 seconds later by a magnitude 7.5 rupture. So-called doublets are uncommon, but not vanishingly so. In September 2025, just southwest of Wednesday’s doublet, a pair of quakes (magnitudes 6.2 and 6.3) caused widespread damage to buildings and injured more than 110 people.

当地时间下午6点04分，首都加拉加斯以西发生7.2级地震；仅39秒后，又发生了7.5级地震。所谓的“双震”虽然不常见，但并非绝无仅有。在2025年9月，就在此次双震的西南方位曾发生6.2级和6.3级的双震，造成大量建筑受损，导致110多人受伤。

The extent of the devastation is not yet clear, and scientists may yet revise their estimates of the quakes’ strength. Over the coming weeks, researchers will gather reams of geologic data and build up a detailed picture of the twin temblors.

目前的受灾程度尚不明确，科学家们可能还会修正对地震强度的评估。在接下来的几周里，研究人员将收集大量的地质数据，以还原此次双震的详细情况。

But they already have an idea as to why these quakes took place in such a remarkably short time and why they were so damaging. Here’s what they know so far about these catastrophic earthquakes, and what to expect in the days to come.

但关于这两次地震为何会在如此短的时间内接连发生，以及为何会造成如此严重的破坏，他们目前已经有了初步推断。以下是目前对这场灾难性地震的了解，以及对未来几天的预测情况。

Why was one strong quake immediately followed by another?

为什么一场强震之后紧接着又发生了一场强震？

During a sequence of earthquakes, the most powerful among them — in this case, the magnitude 7.5 event — is considered to be the main shock, which would make the magnitude 7.2 event the “foreshock.”

在一系列地震中，震级最大的那一次被称为主震——这次的7.5级地震为主震，7.2级地震则属于前震。

These two quakes together are known as a doublet, because of their back-to-back nature at nearly the same location and probably on the same fault, or a closely related group of faults. But Wednesday’s pair was peculiar.

由于两次地震在几乎同一地点接连发生，而且很可能发生在同一断层或彼此密切相关的一组断层上，因此它们共同构成了一次双震。不过，周三的双震相当特殊。

“Most doublets don’t occur quite this close together in time,” said Brandon Bishop, a seismologist at Saint Louis University. “Delays of hours to a few days are much more common.”

“大多数双震在时间上不会靠得这么近，”圣路易斯大学地震学家布兰登·毕肖普指出，“间隔数小时到数天的情况更为常见。”

The timing is almost certainly not a coincidence. “It is very likely that the first triggered the second one,” said Harold Tobin, the director of the Pacific Northwest Seismic Network at the University of Washington.

这两场地震在时间上几乎可以肯定不是巧合。“第一场地震很可能触发了第二场，”华盛顿大学“太平洋西北地震网络”主任哈罗德·托宾说。

The ferocious seismic waves unleashed by the initial rupture may have convulsed an adjacent, locked-up section of the fault, which triggered the second quake. Although these two quakes might be considered separate events, “this could be regarded as one earthquake that went on for 50 seconds or so,” said Stephen Hicks, a seismologist at University College London in England.

第一次断裂释放出的猛烈地震波可能扰动了断层相邻的锁固段，从而引发了第二次地震。尽管这两次地震可能被视为独立事件，但英国伦敦大学学院的地震学家斯蒂芬·希克斯认为，“也可以把它们看作是一场持续了约50秒的大地震。”

Instead of a pause between the two events, it may be better to think of this disaster as a near continuous rupture that “cascaded into this bigger beast,” he added.

他说，与其认为两次地震之间存在停顿，不如把这场灾难理解为一次几乎持续不断的断层破裂，它“一路演变最终发展成了这个更为可怕的巨兽”。

Why were these earthquakes so destructive?

为什么双震的破坏力如此巨大？

Although a magnitude 7.2 event sounds just a little less severe than a magnitude 7.5 quake, this scale isn’t linear. According to scientists, the second quake released almost three times as much energy as the first.

尽管7.2级听起来只比7.5级稍弱一点，但震级并非线性关系。据科学家称，第二次地震释放的能量几乎是第一次的三倍。

Other factors conspired to make this doublet particularly devastating.

此外，还有其他多种因素共同导致这次双震的破坏力异常巨大。

“Both earthquakes are relatively shallow,” said Dr. Bishop. That means that the potency of the seismic waves wasn’t much diminished by the time they coursed across the Earth’s surface.

毕晓普博士说：“这两场地震的震源都比较浅。”这意味着，在传导至地表时地震波能量并未发生太多衰减。

The quakes took place in the Yaracuy Valley, which is filled with loose sediments — the very sort that amplify shaking. This led to landslides and even liquefaction, a temporary state in which soil behaves like a fluid.

地震发生在亚拉奎山谷，那里覆盖着大量松软的沉积物——正是会放大地震晃动的那种地层。这导致了山体滑坡甚至土壤液化，也就是一种土壤暂时表现出流体特性的状态。

And as the fault rupture moved eastward, in the direction of the capital city, Caracas “got a direct hit,” said Dr. Hicks.

希克斯博士指出，随着断层破裂向东扩展，直逼首都方向，加拉加斯受到“正面冲击”。

The fact that Venezuela lacks a technologically sophisticated earthquake early-warning system and is in a state of economic and political disarray only exacerbated the potential for disaster.

此外，委内瑞拉缺乏技术先进的地震预警系统，且长期处于经济与政治动荡状态，这也进一步放大了灾难造成的影响。

周四，加拉加斯西北方向约30公里处的卡蒂亚拉马尔，受地震损毁的房屋。

Is this area prone to earthquakes?

该地区本来就容易发生地震吗？

This region is a messy geologic jigsaw puzzle. The Caribbean tectonic plate is moving eastward relative to the South American plate by less than an inch per year. In one section, the Caribbean plate has also been forced under the South American plate, causing parts of the latter to fragment.

这一地区的地质构造十分复杂，犹如一幅凌乱的拼图。加勒比板块相对于南美板块正以每年不到约2.5厘米的速度向东移动。与此同时，在部分区域，加勒比板块还俯冲至南美板块之下，导致后者部分地壳发生碎裂。

Within a 155-mile vicinity of Wednesday’s earthquakes, there have been seven magnitude 6 or greater earthquakes in the past century. And around the epicenters of this week’s doublet, there are three known significant faults mapped out: the Boconó Fault, the El Guayabo Fault and the Morón Fault.

在周三两次地震震中方圆约250公里的范围内，过去100年里已经发生过七次6级或以上地震。此次双震震中附近目前已知至少分布着三条重要断层：博科诺断层、埃尔瓜亚沃断层和莫龙断层。

The magnitude 7.5 event appears closest to El Guayabo, while the magnitude 7.2 earthquake seems nearest to Morón. But with the uncertainties involved, all three are suspects — and more than one could have ruptured.

7.5级地震似乎最接近埃尔瓜亚沃断层，7.2级地震似乎最靠近莫龙断层。但由于存在不确定性，三条断层都有可能是元凶——而且可能不止一条发生了断裂。

This complexity makes untangling the root cause of Wednesday’s quakes somewhat troublesome. But early indications are that the fault, or faults, that ruptured did so in a strike-slip fashion, meaning two blocks of the crust slipped in a side-to-side manner with respect to each other.

这种复杂性令厘清周三地震的真正成因变得相当困难。但初步迹象表明，发生断裂的断层属于走滑断层，即断层两侧的地壳主要是沿水平方向彼此错动。

“Strike-slip faults tend to produce strong seismic shaking, especially near to and along the length of the fault that moved,” Dr. Tobin said.

“走滑断层往往会产生强烈的地震晃动，特别是在靠近断层沿线及沿断裂带延伸的方向上，”托宾博士说。

“This is analogous to the East Anatolian Fault that devastated Turkey a few years ago, Haiti in 2010, or the San Andreas Fault,” he added.

他补充道：“这与前几年重创土耳其的东安纳托利亚断层、引发2010年海地地震的圣安德烈亚斯断层非常相似。”

Will there be any significant aftershocks?

还会发生较大的余震吗？

They are already taking place. According to the forecasts by the U.S. Geological Survey, the region will be rattled by myriad smaller quakes (magnitudes 3 to 5) over the next week.

余震已经在持续发生。根据美国地质调查局预测，未来一周，该地区将持续发生多次3级至5级的小型地震。

Within this time frame, there is a 24 percent chance of a magnitude 6 event striking the area, and a 3 percent chance of another magnitude 7 quake taking place.

与此同时，该地区未来一周发生6级地震的概率为24%；再次发生7级地震的概率为3%。

“Normally, aftershocks occur most frequently right after a big one, then tail off exponentially over days to weeks to years,” said Dr. Tobin. That means the chaos and fear gripping the nation right now is likely to continue well into the future.

“通常情况下，余震在大震后发生得最频繁，然后随时间推移呈指数级衰减，这一过程会持续数天、数周到数年，”托宾博士表示。这意味着，目前笼罩该国的混乱与恐慌很可能会持续相当长一段时间。