Reverberations felt for miles, caught on cameras in offices along the coast and at an airport.

沿岸辦公室和機場的攝像頭拍到了數英里外的反響。

Please evacuate right now.

請立即疏散。

Tsunami warnings issued following the quake urging some residents to leave the seaside, but so far, injuries and damage have been minimal. Researchers have long warned of a megaquake eight or nine magnitude, potentially even more damaging than the 9.1 that set off a tsunami in 2011 and ravaged Japan's northeast coast. The disaster, one of the worst in this century, killing more than 18,000 people, leaving parts of the country in ruin, including a nuclear disaster at Fukushima that rattled the world.

地震發生後，日本發出了海嘯警報，敦促一些居民離開海邊，但到目前為止，人員傷亡和財產損失都很小。研究人員長期以來一直警告說，八級或九級的特大地震可能比 2011 年引發海嘯並肆虐日本東北海岸的 9.1 級地震更具破壞性。這場災難是本世紀最嚴重的災難之一，造成 18,000 多人死亡，該國部分地區成為廢墟，包括震驚世界的福島核災難。

There was a magnitude 7.3 earthquake that happened two days before that earthquake, and about five percent of the time, we see that there is an earthquake called foreshock that precedes a larger event.

在這次地震的兩天前，發生了一次 7.3 級的地震，大約有 5% 的情況下，我們會看到在更大的地震發生前會有一次被稱為前震的地震。

Japan sits on the circum-Pacific belt known as the Ring of Fire, where tectonic plates meet, leading to lots of quakes and volcanic activity. The U.S.'s Pacific coast also on the Ring of Fire.

日本位於被稱為 "火環 "的環太平洋地帶，板塊在此交匯，導致地震和火山活動頻發。美國的太平洋海岸也位於火環上。

Southern California just getting hit with a 5.2 magnitude quake Wednesday.

南加州週三剛剛發生 5.2 級地震。

Experts believe we should be ready for one of those megaquakes too.

專家們認為，我們也應該做好應對這種特大地震的準備。

There's a lot of effort being put into preparing for such an event in terms of both the seismic hazard, the ground shaking, and the tsunamis.

為了應對地震災害、地表震動和海嘯，我們付出了很多努力。

Preparing for what seems unthinkable, but might be inevitable.

為看似不可想象，但可能不可避免的事情做好準備。

Dana Griffin, NBC News.

Dana Griffin，NBC 新聞。

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感謝您的收看。通過 NBC News 應用程序或在社交媒體上關注我們，隨時瞭解最新突發新聞和熱門事件。