FORESTRY
SOIL SCIENCE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
cooled rock inside a volcano
|
|
|
cooled rock outside a volcano
|
|
|
melted rock inside a volcano
|
|
|
melted rock outside a volcano
|
Detailed explanation-1: -Scientists use the term magma for molten rock that is underground and lava for molten rock that breaks through the Earth’s surface.
Detailed explanation-2: -Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from 800 to 1, 200 °C (1, 470 to 2, 190 °F). The volcanic rock resulting from subsequent cooling is also often called lava.
Detailed explanation-3: -Lava is what we call the molten rock that flows from an active volcano, after it’s exposed to the air. Underground it is called magma. So, the lava rocks in your garden are really an igneous rock – meaning hardened lava. It’s volcanic rock, specifically, most landscaping lava rock is a type of rock called obsidian.