An earthquake measuring 2.1 on the Richter scale was felt on Wednesday night in municipalities in the districts of Porto and ...

Earthquakes are measured using seismographs, which monitor the seismic waves that travel through the Earth after an earthquake strikes. Scientists used the Richter Scale for many years but now largely ...

Earthquake strength is registered on the moment magnitude scale, which measures how much energy was released when the rocks along a fault moved during the quake. By Henry Fountain Earthquake strength ...