What is going on?
A magnitude 8.3 earthquake strikes the south of Samoa on Tuesday, triggering a tsunami. Then, 16 hours later, a magnitude 7.6 quake occurs 30 miles off the east coast of the Indonesian island of Sumatra.
Why has there been a large amount of seismic activity in the Asia-Pacific region over the past few weeks? Clive Collins, Senior Seismologist for GeoScience Australia, gives us some answers:
Samoa and Indonesia are just over 6,000km apart. Are these earthquakes, only 16 hours apart, linked?
The short answer, says Collins is that “we don’t know, we don’t think they are linked directly”. Although there is “some evidence that sometimes large earthquakes can cause distant earthquakes to occur some time later”, Collins says that there is “no proved cause and effect”.
While it is unlikely that the earthquake near Samoa caused the earthquake in Indonesia, “in the big picture they are linked as they are both on same tectonic plate”. In layman’s terms, both earthquakes are “due to the movement of the Australian plate”.
Over the last few weeks there has been considerable activity around the Australian plate, in Java, Maluku and even the south-eastern suburbs of Melbourne. What’s going on?
“The earth’s plates are always moving,” says Collins. “The Australian plate is drifting north whilst the South Pacific plate is moving westwards” and when these plates meet, seismic activity is triggered.
More specifically, in the case of the earthquake in Samoa, “the Pacific plate is being pushed underneath the Australian plate” and this activity causes “breakages and build-up of pressure which causes earthquakes”.
Is it possible that this seismic activity could cause any volcanic activity?
Yes. As the plates meet and crash, says Collins, “debris from the crash heats up and melts”. Then, as it moves down deeper under the plate “it eventually has nowhere to go and gets pushed upwards”. The result: a volcanic eruption.
Are more earthquakes expected?
Lots of aftershocks and small earthquakes are expected, says Collins. However, “we don’t know if there will be another large one in the same place in the near future. [However] areas to the south and the north of the breakages may break and cause more earthquakes.” [After this interview was conducted reports started coming in that another major earthquake had hit Sumatra]
There has been an increase in seismic activity in the Indonesian fault line since the 2004 Asian tsunami. What causes such an upswing in earthquakes?
According to Collins, “this was such a big event and caused a whole lot of the boundary to break which puts pressure and stress on the rocks and surrounding areas”. Yet, while “earthquakes occur in clusters, if you look at a long enough time span, on average, the rate of earthquakes doesn’t change”.
Could this be at all related to the effects of climate change?
“Not directly, not these ones, this will happen regardless,” assures Collins. Other earthquakes though “may be related [to climate change]. If, for example, the polar ice caps melt you get more water in oceans or more weight in some places or pressure released in some places” which can cause plates to shift and earthquakes to occur.
Can Will Smith really save us?
“Who knows, he can have a try. It’s a bit of an uphill battle.”
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What the?!!!!! I know you’re an intern and all so I’m sorry for this but what an absolutely goddamn moronic thing to ask. “Could this at all be related to the effects of climate change?” Wake up! How brainwashed are you people? Climate change is happening, it’s always happened and it always will happen. Tectonic plate shifts too have always happened and always will happen. It’s nature, and nature can kill. If the climate change propagandists have been so effective that a wanna-be reputable organ like Crikey can query a “link” between an earthquake and climate change, now I do fear for the future. And fyi, if ice caps melt there will be enormous earthquakes, it’s called isostatic rebound, and it too is 100% natural. You should have been around in 16,000 BC and 11,000 BC when there were rapid ice melts and the oceans rose quickly. The climate change alarmists back then made sacrifices to the gods to stop it.
”due to the movement of the Australian plate” – Shhh! Don’t say that, those pesky Indonesians will blame us for it! :^)
Erratum (Moot point): The Sumatran earthquake struck off the west coast of Sumatra not the east coast.
“…Could this be at all related to the effects of climate change?
“Not directly, not these ones, this will happen regardless,” assures Collins. Other earthquakes though “may be related [to climate change]. If, for example, the polar ice caps melt you get more water in oceans or more weight in some places or pressure released in some places” which can cause plates to shift and earthquakes to occur…”
24K Comedy GOLD!!
Using Collins’ rationale, if the entire population stood at either of the poles we could flood the globe.
Great stuff…thanks for the laugh, Mel.
There was a brief mention of another earthquake on the ABC news this morning, but I have heard no follow up, apparently there was a 6.3 quake near La Paz, in Peru.