HONOLULU (KHON2) — In early August, Japan issued a significant warning about the possibility of a mega quake. This alert, although later rescinded, highlighted a real and pressing concern about the potential for a massive earthquake.
To better understand this warning, KHON2.com spoke with Dr. Michael Blanpied, the Associate Coordinator for the USGS Earthquake Hazards Program.
Dr. Blanpied shared his expertise on mega quakes, their historical context, their impact on regions like Japan and what if any concerns Hawaiʻi may need to have.
What is a mega quake?
A megaquake is a term used to describe exceptionally powerful earthquakes, typically with a magnitude of 8.0 or greater.
Dr. Blanpied explained that these colossal quakes usually occur at subduction zones, where one tectonic plate is forced beneath another.
“In these regions, stress accumulates over long periods because the plates are not moving smoothly,” Dr. Blanpied noted. “Eventually, when the stress becomes too great, the plates suddenly slip, causing a powerful earthquake.”
Japan’s location on the Pacific Ring of Fire makes it particularly vulnerable to megaquakes. This region, known for its intense seismic activity, is where several tectonic plates converge.
Dr. Tanaka elaborated on Japan’s susceptibility: “Japan is situated at the intersection of multiple tectonic plates, which means it is prone to frequent seismic activity, including megaquakes. Our recent warning was a precautionary measure in response to the complex seismic dynamics in this area.”
Historical patterns and the current threat
Mega quakes are not as rare as one might think. According to Dr. Blanpied, subduction zones around the world can produce these enormous earthquakes.
In the United States, the Cascadia subduction zone off the coast of northern California, Oregon and Washington is known for its potential to generate mega quakes.
Historical evidence shows that a magnitude 9.0 earthquake occurred in this region in 1700. The seismic activity in this area is closely monitored due to the possibility of a future similar event.
Japan’s current concern centers on the Nankai Trough, a major subduction zone off southeastern Japan. Dr. Blanpied noted that Japanese scientists recently updated their studies, indicating a high probability—70 to 80 percent—of a large earthquake in the coming decades.
The warning issued earlier this month was based on this research and was meant to prepare the public for potential seismic activity.
The 2011 Tōhoku Earthquake
The 2011 Tōhoku earthquake, also known as the Great East Japan Earthquake, is a prime example of a megaquake.
With a magnitude of 9.0, it was one of the most powerful earthquakes ever recorded. The earthquake not only shook Japan but also generated a devastating tsunami that wreaked havoc on the northeastern coast.
“The 2011 Tōhoku earthquake was a stark reminder of the immense power and destruction associated with megaquakes,” explained Dr. Blanpied. “It highlighted the importance of preparedness and early warning systems to mitigate the effects of these natural disasters.”
The disaster led to the Fukushima Daiichi nuclear crisis, highlighting the severe impact such events can have on both human and environmental systems.
Impacts and preparations
When a mega quake occurs, it can cause severe shaking over a broad area, impacting densely populated regions like Tokyo.
Dr. Blanpied emphasized that such an earthquake would bring about long-lasting shaking, significant damage to infrastructure, and potentially a tsunami.
“Japan is situated at the intersection of multiple tectonic plates, which means it is prone to frequent seismic activity, including megaquakes,” said Dr. Blanpied. “Our recent warning was a precautionary measure in response to the complex seismic dynamics in this area.”
The 2011 Tōhoku earthquake demonstrated how tsunamis can devastate coastal areas, overcoming even well-constructed sea walls.
In preparation for these events, Japan has implemented various measures, including building tsunami walls and improving early warning systems.
“The alert was based on observed seismic activity and modeling, which indicated a higher-than-usual likelihood of a significant earthquake,” explained Dr. Blanpied. “However, after further analysis, we determined that the immediate threat had subsided, and the alert was rescinded.”
Despite these efforts, the combination of strong shaking and high tsunamis poses a significant risk. The Japanese government is continually working to improve its preparedness and response strategies to protect its citizens.
The unpredictability of earthquakes
One of the most challenging aspects of earthquakes is their unpredictability. Unlike weather events, earthquakes cannot be forecasted with precision.
“Predicting the exact timing and location of earthquakes remains one of the biggest challenges in seismology,” noted Dr. Blanpied. “Despite advancements in technology, earthquakes can still occur unexpectedly and without precise warning.”
Dr. Blanpied pointed out that while scientists can estimate the likelihood of a mega quake based on historical data and current research, predicting the exact timing of such an event remains elusive.
“While we can estimate the likelihood of seismic activity in a region based on historical data and current conditions, the precise prediction of when and where an earthquake will strike is still beyond our reach,” added Dr. Blanpied.
For travelers to earthquake-prone regions, Dr. Blanpied recommended staying informed about local hazards and knowing safety protocols.
Whether visiting Japan, California, or other seismic hotspots, being prepared for the possibility of an earthquake can help ensure safety.
But Dr. Blanpied cautioned that “earthquakes are inherently unpredictable due to the complex nature of tectonic plate movements and the buildup of stress along faults. This unpredictability is why preparedness and robust response strategies are crucial for minimizing damage and saving lives.”
Be prepared when visiting Japan
When visiting Japan, it’s important to be prepared for earthquakes because Japan is a place where they happen quite often. Here’s what you need to know about preparing for and dealing with an earthquake warning:
Know the safety procedures: Before you even leave for Japan, learn about what to do if an earthquake happens. In Japan, they have special earthquake alarms that make loud noises when a big quake is coming. These alarms are a warning that you need to be ready!
“When you’re in a building during an earthquake, get under a sturdy table or desk to protect yourself from falling objects. Stay away from windows and anything that might pose a danger,” said Dr. Blanpied.
Have an emergency kit: Make sure you have an emergency kit with things you might need if an earthquake happens. This kit should include items like water, snacks, a flashlight, batteries, a first aid kit, and important documents. It’s a good idea to pack these things in a bag that’s easy to grab quickly.
“Make sure you have an emergency kit with items like water, snacks, a flashlight, batteries and a first aid kit,” explained Dr. Blanpied. “It’s essential to be ready for any situation that might arise during an earthquake.”
Find safe spots: When you are in your hotel or another building, know where the safe places are. During an earthquake, you should get under a sturdy table or desk to protect yourself from falling objects. Stay away from windows and anything that might fall.
Follow instructions: If an earthquake happens or you hear an alarm, listen carefully to announcements and follow instructions from local authorities. They will tell you the best ways to stay safe.
Stay informed: Pay attention to local news and follow guidance from hotel staff or tour guides, as they are familiar with local emergency procedures.
“Listen carefully to announcements and follow instructions from local authorities,” added Dr. Blanpied. “They will guide you on the best ways to stay safe when an earthquake occurs.”
Practice safety drills: Practice what you would do if an earthquake happened. For example, you can practice getting under a table and staying there for a few seconds. This will help you remember what to do when you hear the alarm.
By being prepared and knowing what to do, you can stay safe and calm during an earthquake while visiting Japan.
USGS readies response for megaquake
In the event of a megaquake, the United States Geological Survey (USGS) will spring into action to help keep everyone informed and safe. Here’s what you can expect from their response:
Dr. Blanpied explained that first, the USGS will quickly provide detailed information about the earthquake. They will use advanced technology to pinpoint where the quake occurred and measure its strength. This helps people understand the scope of the event and what to anticipate.
“The USGS will quickly provide information about the earthquake, like where it happened and how strong it was,” revealed Dr. Blanpied. “This helps everyone understand what to expect.”
Next, the USGS will send out timely updates and warnings. They will alert the public about any aftershocks or additional dangers, ensuring that everyone remains aware of ongoing risks and can take necessary precautions.
“They will send out updates and warnings to help people stay safe,” said Dr. Blanpied. “If there are any aftershocks or more problems, they will keep everyone informed.”
Finally, the USGS will coordinate with other agencies to support emergency response efforts. They will assist in rescue operations and offer guidance to help communities recover from the quake’s impact.
“The USGS will work with other agencies to help with emergency responses. They will help guide rescue efforts and provide advice to help communities recover.”
“The USGS will work with other agencies to help with emergency responses. They will help guide rescue efforts and provide advice to help communities recover.”
“The USGS will work with other agencies to help with emergency responses,” added Dr. Blanpied. “They will help guide rescue efforts and provide advice to help communities recover.”
By delivering prompt information, continuous updates, and coordinating rescue efforts, the USGS plays a crucial role in managing the aftermath of a megaquake and supporting affected communities.
Looking forward
While the mega quake warning in Japan was rescinded, the threat of a future large earthquake remains. Dr. Blanpied stressed the importance of ongoing research and monitoring to understand and mitigate these risks.
The USGS, for example, provides aftershock forecasts and updates on seismic activity to help communities prepare and respond effectively.
The recent alert in Japan serves as a reminder of the ever-present risk of mega quakes. Understanding these events, their potential impacts, and how to prepare can help mitigate the effects of these powerful natural disasters.
For more information on earthquake preparedness and to stay updated on seismic activity, the USGS provides valuable resources and data on their website.
You can click here for more information on how USGS updates and offers information to the public. You can click here for more information on how to track aftershocks. You can watch Dr. Blanpied’s full interview in the video above.
As we continue to learn more about earthquakes and improve our preparedness, it is crucial to remain vigilant and informed.