Understanding Japan’s Megaquake Alert: Implications and Insights

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% probability of an earthquake 8.0 or increased offshore this week. That, in fact, shouldn’t be doubtless. But when it did occur, in response to a report by the Japanese authorities, it will have the potential to provide a tsunami of as much as 98 toes excessive, placing the lives of 200,000 folks at speedy danger. So how will we preserve folks 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 enormous earthquakes, within the case of Japan, in subduction zones. Though, we will 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 among the oceans, the place you will have oceanic plate diving down beneath the continental plate adjoining to it or one other oceanic plate. As a result of you will have that vertical movement with the plate subducting, that is the way you generate tsunamis. In California, we expect extra about strike-slip faults. And San Andreas Fault is a strike-slip fault, the place the 2 plates are transferring 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 folks about what is going on to occur versus inflicting a panic about it?

ALLEN: So it is vital that we, the scientific neighborhood, let the general public learn about that and being very clear that sure, there is a increased likelihood of a megaquake this week, but it surely’s nonetheless a low likelihood. And so it is a terrific alternative for folks to be fascinated 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 will happen sooner or later, and so everyone must be prepared.

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

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

However then the second piece is, what will we as people do? All of us need to be liable for ourselves and for the folks round us. All of us must know what’s it we should always do once we get the earthquake warning or once 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 vital to get to increased floor. If you happen to’re residing in a coastal area, it is advisable know that you simply’re in a tsunami hazard zone, and it is advisable know the way far it is advisable evacuate as a way to get out of that hazard.

SCHMITZ: Now, you are standing there in California. Clearly, California, the remainder of the West Coast can also be liable 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 will have an earthquake, there’s a 1 in 20 probability that there shall be a bigger earthquake that follows it. And so now we have related sorts of knowledge techniques. They’re delivered by the USGS. If you happen to go to the USGS webpages following an earthquake, you will notice graphics that designate the chance 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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