Big Earthquakes May Be More Likely During New and Full Moons
新月和满月时更易发生大地震

When the sun, moon and Earth are aligned, high tidal stress may increase the chances that an earthquake will grow bigger than it otherwise might have been.
当太阳、月球、地球连成直线，高强度潮汐应力会有更大的可能使得原本可能发生的地震变得更强烈。

撰文/播音：朱莉娅·罗森（Julia Rosen）
翻译：杨枭
审校：丁可含

Every two weeks, on the full and new moons, the sun, moon and Earth fall along a nearly straight line. The combination of gravitational forces in this arrangement creates large swings in the tides. But the celestial alignment affects more than the oceans—it also tugs on Earth’s crust, adding to the stress on faults. This makes it more likely that major earthquakes will strike at these times, according to a new study.
每两个星期，在满月和新月时，太阳、月亮和地球会近乎连成一条直线。此时引力合力会对潮汐产生巨大的摆动。然而据一项新研究表明，这一天象不仅仅影响海洋——它同时也会对地壳有牵引力，增加断层间的压力。这将导致这一时期的大地震更有可能发生。

The idea isn’t new, but scientists have had a hard time testing the earthquake-tide relationship. For instance, three of the largest earthquakes in recent years happened when tidal stress was high. But those big ones are rare and the link seems to break down for smaller events.
这并非一个新观点，但科学家很难检测地震与潮汐间的关系。举个例子，最近几年最大的三次地震都发生在潮汐应力很强的时候，然而大地震太罕见，使得二者间的此种连系仅适用于小概率事件。

So the researchers crunched a bunch of numbers: by looking at more than 10,000 medium and large earthquakes, they found that the proportion of large events increased when tidal stress was high.
因此，研究者通过观测超过1000次大中型地震而收集了一堆数据，他们发现潮汐应力增强时，大地震的比例会随之增多。

The results do not imply that every full or new moon will bring an earthquake—obviously. What the findings mean is that high tidal stress during new or full moons may up the chances that an earthquake will grow bigger than it otherwise might have been.
显然，该结果并不能说明每次满月或是新月时就会有地震发生。研究结果只是说明新月或满月时的高强度潮汐应力会有更大的可能使得原本可能发生的地震变得更强烈。

“Even magnitude 9 earthquakes start like magnitudes 1 or 2.” Satoshi Ide, the University of Tokyo seismologist who led the study. “So, at the initial stage, it’s very difficult to distinguish small or large earthquakes. It starts similarly, but it grows at some probability to large scale. That probability is controlled by some other effect.”
东京大学的地震学家Satoshi Ide领导了这项研究，他说，“即使是9级地震开始都可能像一两级的。因此在地震初期很难去区分是小地震还是大地震。地震开始很相似，但会以某种概率而发展到巨大的规模。而这种概率又受其他因素影响。”

And one of those effects might be the tides. Ide points out that tides in the Earth’s crust are known to cause tiny tremors along deep faults. “Earthquake faults are locked everywhere, but that kind of slow deformation unlocks very small part of the fault…so it doesn’t make large failure there, but once earthquake rupture starts…it can propagate very far and become very large earthquake.”
而其中一种影响可能就是潮汐。Ide指出，我们已知潮汐会在地壳中沿着深层断层引起微小振动。“地震断层无处不在紧密相连，但那种缓慢的变形会让小部分断层松动……因此，它虽然不会造成大影响，但一旦地震断裂开始……它就会蔓延广远并演变成巨大的地震。”

The study was published in the journal Nature Geoscience. [Satoshi Ide, Suguru Yabe and Yoshiyuki Tanaka, Earthquake potential revealed by tidal influence on earthquake size–frequency statistics]
该研究发表在《自然 地理学》上。

Ide is now doing a similar analysis on earthquakes that all happened in the same geologic setting, like subduction zones. Perhaps that research will confirm whether heavenly bodies can take smaller shakes and supersize them.
 Ide正在对所有发生在同一地质环境中的地震进行类似的分析，例如俯冲带。或许这项研究将确认天体是否可以产生较小的震动并加剧这些地震。