Why Major Earthquakes Hit Mexico, Defined

So far, 2017 has actually been a “quiet year” for earthquakes, Dr. Hayes said.
In fact, earthquakes with a magnitude of 9.0 or higher can occur only in subduction zones, Dr. Hayes said.
The more recent quake was much closer to Mexico City, which Dr. Hayes said is built on a sedimentary basin.
Oklahoma has had issues in recent years with what Dr. Hayes called “human-induced” earthquakes, which are the result of wastewater being pumped into the ground.
Why weren’t the Mexico quakes even stronger?

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