Japan is underneath a megaquake watch. What does this imply? : NPR

ROB SCHMITZ, HOST:

It has been an unsettling few days in Japan. A 7.5 magnitude earthquake off the coast of the nation on Monday put the nation on what’s referred to as a megaquake watch. Seismologists say there is a 1% likelihood of an earthquake 8.0 or greater offshore this week. That, in fact, just isn’t possible. But when it did occur, in response to a report by the Japanese authorities, it will have the potential to supply a tsunami of as much as 98 ft excessive, placing the lives of 200,000 individuals at rapid danger. So how will we hold individuals knowledgeable with out inflicting a panic? We’re joined now by Richard Allen, director of the Berkeley Seismology Lab in California. Welcome, Richard.

RICHARD ALLEN: Nice to be with you.

SCHMITZ: So, Richard, what’s a megaquake?

ALLEN: So these are the really large earthquakes, within the case of Japan, in subduction zones. Though, we are able to have magnitude 8 earthquakes in strike-slip faults right here in California as nicely.

SCHMITZ: Richard, you simply talked about a subduction zone. For these of us who do not know what that’s, inform us what that’s.

ALLEN: Certain. So a subduction zone are across the margins of a few of the oceans, the place you’ve got oceanic plate diving down beneath the continental plate adjoining to it or one other oceanic plate. As a result of you’ve got that vertical movement with the plate subducting, that is the way you generate tsunamis. In California, we predict extra about strike-slip faults. And San Andreas Fault is a strike-slip fault, the place the 2 plates are shifting sideways subsequent to one another, and so you do not anticipate a tsunami on a strike-slip fault.

SCHMITZ: So how do officers stability informing individuals about what is going on to occur versus inflicting a panic about it?

ALLEN: So it is essential that we, the scientific group, let the general public learn about that and being very clear that sure, there is a greater chance of a megaquake this week, but it surely’s nonetheless a low chance. And so it is a fantastic alternative for individuals to be interested by, how are they going to react? Are they able to react when a big magnitude earthquake and a tsunami like that come? As a result of even when it would not come this week, they’ll happen sooner or later, and so all people must be prepared.

SCHMITZ: What sort of protocol has Japan put into place to arrange the inhabitants for a quake like this?

ALLEN: Properly, there’s two units of preparations that individuals need to make. It is what do the establishments, what does authorities do, after which what will we as people do? So to begin with, for establishments, for the federal government, what they put in place is warning methods. We have now to supply individuals with the warning, and we kind of hit the go button so individuals can begin to take their actions.

However then the second piece is, what will we as people do? All of us need to be chargeable for ourselves and for the individuals round us. All of us must know what’s it we should always do after we get the earthquake warning or after we really feel shaking. We must always know that we have to do drop, cowl, maintain on. After which within the case of the tsunami, in fact, it is actually essential to get to greater floor. When you’re residing in a coastal area, it’s essential know that you just’re in a tsunami hazard zone, and it’s essential understand how far it’s essential evacuate to be able to get out of that hazard.

SCHMITZ: Now, you are standing there in California. Clearly, California, the remainder of the West Coast can be vulnerable to earthquakes. I am simply curious, does the U.S. have the same system than Japan so far as these megaquake warnings?

ALLEN: So what now we have is now we have aftershock warnings. So it is really well-known in California, for instance, that there – when you’ve got an earthquake, there’s a 1 in 20 likelihood that there will likely be a bigger earthquake that follows it. And so now we have related varieties of knowledge methods. They’re delivered by the USGS. When you go to the USGS webpages following an earthquake, you will note graphics that specify the probability of aftershocks, together with the potential for a larger-magnitude earthquake as nicely.

SCHMITZ: That’s Richard Allen, director of the Berkeley Seismology Lab in California. Richard, thanks a lot for becoming a member of us.

ALLEN: Nice. Glad to be with you.

(SOUNDBITE OF DJ HARRISON’S “ERYKAH’S GUN”)

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