A massive undersea earthquake is long overdue beneath the Mentawai Islands in Indonesia and could trigger another deadly tsunami.
Unlike the 2004 Indian Ocean tsunami which killed about 226,000 people, this tsunami is expected to be smaller but may be very deadly as it would hit Sumatera's densely populated coast, according to Kerry Sieh, director of the Singapore-based Earth Observatory.
A major quake measuring around 8.6 magnitude is expected beneath Siberut Island, along the Sunda megathrust, where the Indonesia-Australian tectonic plate butts up against the Eurasian plate.
Sieh said, the big quake will most likely strike in next few decades, somewhere from thirty seconds to 30 years. He predicted such occurance of the quake based on the study of geological records which showed that major quakes have occured along the Sunda megathrust every 200 years for the past 700 years.
According Sieh, there have been three major quake cycles: the late 1300s, the 1600s and between 1797 - 1833 and the timing between those three sequences is about 200 years. Therefore the next cycle will be between now and the next 30 years!
The Sunda megathrust extends from Myanmar in the north and sweeps in a south-east arc through Sumatera, Java and towards Timor.
In 2004, the northern 1,600 km section, from Myanmar to Acheh, ruptured, sending the Indian Ocean tsunami that killed about 226,00 people.
In March 2005, a powerful quake hit the second section near Nias Island, though there was no occurance of tsunami but causing more than 11m defomations beneath the island.
In 2007, an 8.4 and a 7.8 earthquake hit the southern end of the third section, called the Mentawais Patch.
In September 2009, an earthquake hit Padang, Sumatera but that quake resulted not from the rupture of the megathrust beneath the Mentawais but was on a deeper fault.
This means that another 300 km section of the northern part of the Mentawai Patch has not yet broken up into a quake. The last time this section has broken up into a quake was in 1797.
So, from now on to the next 300 years, anytime, a massive quake could occur from that section of the Mentawai Patch and it could create a significant tsunami and deadly too. Be alert to those who frequent to enjoy yourself at the beaches surounding the area!
A major quake measuring around 8.6 magnitude is expected beneath Siberut Island, along the Sunda megathrust, where the Indonesia-Australian tectonic plate butts up against the Eurasian plate.
Sieh said, the big quake will most likely strike in next few decades, somewhere from thirty seconds to 30 years. He predicted such occurance of the quake based on the study of geological records which showed that major quakes have occured along the Sunda megathrust every 200 years for the past 700 years.
According Sieh, there have been three major quake cycles: the late 1300s, the 1600s and between 1797 - 1833 and the timing between those three sequences is about 200 years. Therefore the next cycle will be between now and the next 30 years!
The Sunda megathrust extends from Myanmar in the north and sweeps in a south-east arc through Sumatera, Java and towards Timor.
In 2004, the northern 1,600 km section, from Myanmar to Acheh, ruptured, sending the Indian Ocean tsunami that killed about 226,00 people.
In March 2005, a powerful quake hit the second section near Nias Island, though there was no occurance of tsunami but causing more than 11m defomations beneath the island.
In 2007, an 8.4 and a 7.8 earthquake hit the southern end of the third section, called the Mentawais Patch.
In September 2009, an earthquake hit Padang, Sumatera but that quake resulted not from the rupture of the megathrust beneath the Mentawais but was on a deeper fault.
This means that another 300 km section of the northern part of the Mentawai Patch has not yet broken up into a quake. The last time this section has broken up into a quake was in 1797.
So, from now on to the next 300 years, anytime, a massive quake could occur from that section of the Mentawai Patch and it could create a significant tsunami and deadly too. Be alert to those who frequent to enjoy yourself at the beaches surounding the area!
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