A 6.1-magnitude earthquake has struck Japan 175 miles from the Fukushima nuclear plant

Less than 24 hours after a 7.1-magnitude earthquake pummelled Mexico City, another tremor has occurred off the east coast of Japan.

The 6.1-magnitude quake struck roughly 175 miles east of the shuttered Fukushima nuclear plant at roughly 2:30 a.m. local time, according to the US Geological Survey. Its hypocenter — the underwater locus of the quake — happened at a depth of about 6 miles.

Screen Shot 2017 09 20 at 11.16.54 AMUSGSA map of the tectonic plate forces that subject Japan to earthquakes.

Like Mexico, Japan is located in what is considered an active earthquake region.

The country is influenced by the slipping and sliding of several of Earth’s tectonic plates, including the North America plate, Pacific plate, Philippine Sea plate, and Eurasia plate. Whenever these pieces of crust grind or butt up against one another, earthquakes happen.

Over the past century, Japan has been struck by nine severe earthquakes, each of which killed more than 1,000 people.

Part of the problem is the country’s high population density, which can make even shallow temblors a serious risk.

In 1995, an earthquake along the Japan Median Tectonic Line near Kobe lead to more than 5,000 deaths.

More recently, the magnitude 9 Tohoku earthquake in 2011 killed more than 20,000 people after it triggered a tsunami that generated powerful waves up to 133 feet tall. That earthquake occurred just 43 miles east of inhabited land and its underwater hypocenter was close to three times as deep.

This is a developing story.

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