What does the ancient earthquake detector do? it help tell the direction of where it came from and the slightest movement will make the ball fall if you are referring to the ancient china one Edit
Depending on the type of lava flow, the resulting rocks look very different. This was a pahoehoe flow. A lava flow is caused by a volcanic eruption. The lava can flow down the volcano at speeds ranging from 1/24 to 50 meters an hour. They can be 1,300 degrees fahrenheit or more. They are very destructive.
A volcano is an opening in the Earthâs crust from which magma (hot molten rock), ash and gases escape. Volcanic eruptions are driven, in part, by pressure from dissolved gas, much as escaping gases force the cork out of a bottle of champagne.When magma erupts, it is called lava. The type of volcano that forms depends on whether the lava is viscous (thick and sticky) or runny, and on how much gas it contains.If lava is runny, gases escape easily. A runny lava with lots of gas forms fire-fountains that spew into the air and break into globs that solidify as they fall to the ground.olcanic eruptions are driven, in part, by pressure from dissolved gas, much as escaping gases force the cork out of a bottle of champagne. When magma erupts, it is called lava. The type of volcano that forms depends on whether the lava is viscous (thick and sticky) or runny, and on how much gas it contains.