1.   For example, whenever a Fresno seismograph detects an earthquake in the Bay Area, it detects two different seismic waves, Holzer says.

2.   From eight seismometers placed at strategic locations around the volcano, scientists can detect the earthquakes that tell them when magma is forcing its way toward the surface.

3.   Authorities issued a volcano warning Saturday for Mount Asama in central Japan after earthquakes were detected in the area.

4.   It said it began detecting small earthquakes beneath the volcano several weeks ago.