The eruption of magma from the Earth's crust, gas and ash eruption, often with signal indications as to predict earthquakes in the surrounding area. Volcanic vibration Sounding like thunder The sound is caused by the movement of magma, gases and steam, compressed. When the eruption, lava rocks, dust, volcanic ash. Is sprayed out of the crater or out of the slot on the side of the volcano. Or traces of volcanic rift When magma rising to the surface of the Earth is called "lava" (Lava) lava onto the Earth's surface temperatures up to 1.200 ⁰C along the slope of the area.