Google has added an earthquake warning system to mobile phones equipped with the Android operating system. When an earthquake occurs, each Android phone can detect fluctuations from the source of the earthquake, and then warn users in advance that the earthquake is coming.
Google explained that every Android phone has a built-in accelerometer to detect the movement speed and various activities of the device, and it can also be used as a small seismograph.
When the mobile phone detects a suspected seismic wave, it will send a signal to the detection server and provide seismic source information. After analysis, the earthquake warning will be issued to all users who may be affected.
The seismic waves that can be detected by the accelerometer include the P wave, which conducts faster, and the S wave, which conducts slowly but has greater destructive power.
Therefore, when the mobile phone receives the P wave signal, it can at least notify the user a few seconds before the arrival of the S wave to take appropriate precautions. The alarm system will only be triggered when it encounters an earthquake of magnitude 4.5 or higher.
Google said that if every Android phone has the function of detecting earthquake data and amassing millions of Android phones around the world, it is equivalent to building a super-large earthquake detection system.
Hazel Yu 
Iman iman 
Jane Brown 
Mike Lee-111