Taipei
14 July 2009
Scientists say that typhoons which hit Taiwan unleash slow earthquakes,
a phenomenon that may save the island from devastating temblors.
Taiwan is often hit by strong typhoons, or tropical cyclones.
And
while they are dangerous, typhoons help supply the island with water,
but they also may do something else beneficial. Scientist believe
typhoons may actually reduce the occurrence of catastrophic earthquakes.
Liu
Chi-Ching of the Institute of Earth Sciences at Academia Sinica in
Taipei and researchers from the Carnegie Institution in Washington,
D.C., studied a section of a fault line off Taiwan's coast.
They were surprised to see that typhoons seem to affect the movement of the tectonic plates that meet at the fault.
Dr. Chi-Ching explains, "The decrease of the air pressure when typhoon comes, also decrease the pressure in the rock."
A
typhoon causes a fall in atmospheric pressure, and the scientist
researchers suggest that this in turn reduces pressure on the land over
the fault.
One side of the fault lifts slightly, causing the pressure that has been building up inside to be released.
The
gradual release of the pressure causes a slow earthquake, occurring
over hours or days, reducing the likelihood of a violent earthquake.
Dr.
Chi-Ching says, "There's another way other than a normal earthquake
which we call slow earthquake which release a major part of energy in
the crust. That would make us more relaxed because the possibility of
big earthquake will be less."
Typhoon Lee is an Academia Sinica astrophysicist. He says the discovery adds another piece to the puzzle of earthquakes.
Dr.
Lee expresses, "There is still some gap [on] how much energy you would
have and how much energy released by earthquakes. I think we are on the
right track. This is the first important result and certainly won't be
the last."
Researchers will continue to study the fault line
and hope to expand their research further along the same plate boundary
in eastern Taiwan.