A computer-generated illustration of the 'Zhang Heng' electromagnetic test satellite in space. Photo: CNR
A computer-generated illustration of the 'Zhang Heng' electromagnetic test satellite in space. Photo: CNR

Chinese scientists have developed a novel earthquake-monitoring system that reportedly would be able to sound the alarm for authorities to start evacuations at least one day and as much as 15 days ahead of a big quake, according to Science and Technology Daily.

The system is able to detect earthquake precursors to develop patterns for prediction, said the system’s chief scientist Wang Xinan, who led a team at an earthquake monitoring and prediction research center based in Shenzhen.

Specifically, the system is placed underground or in large caves to detect sounds and other signs typical of occurring before an earthquake. And unlike traditional bulky monitoring instruments, the system is made up of a small group of compact and lightweight, ultra-sensitive semiconductor sensors.

These sensors picked up signals when a 6.5-magnitude earthquake struck offshore near Taiwan’s Hualien county on Tuesday.

Though still in early trials, the system has already proved its effectiveness in predicting two small earthquakes in southwestern China’s Sichuan province last September and October.

The center has installed 200 sets of monitoring systems underground and in caves throughout the country, mostly in Sichuan and Yunnan provinces, which straddle two tectonic plates that grind against each other, as well as in Beijing and its surrounding areas.

Early this month, China also launched an electromagnetic test satellite into sun-synchronous orbit that was named after Zhang Heng, an ancient polymath who invented the world’s first seismometer. The satellite carries an inductive magnetometer, a magnetic tester, and an electric-field detector for seismological observation.

It has started monitoring the real-time dynamics of the ionosphere and will monitor for signs of impending earthquakes by collecting data on the global electromagnetic field, energetic particles, and more, according to People’s Daily.

Earthquakes affect electromagnetics by cutting the Earth’s magnetic lines and emitting electromagnetic radiation.

In 2003, the US launched an earthquake-forecast satellite that studied the relationship between magnetic fields and rock fractures.

One year later, France and Ukraine launched electromagnetic satellites to study the changes in the ionosphere connected to quakes and volcanic activity.