|
|
| Why are the first minerals to crystalize the last to melt when the rock is heated? |
Because it takes such a high temperature to be melted as soon as it cools it crystalizes inside it doesnt take as high of temperature to stay molten |
| What is the diffrence between extrusive and in trusive rocks? |
Extrusive-fine grained, cool quickly on earths surface
Intrusive-coarse grained, cool slowly, beneath earths surface |
| How do temperature and pressure change as a mass of magam moves upward through the Earths crust? |
Temperature and pressure decrease |
| What are 3 ways magma is classified? |
Basaltic-least amount of silica
Andesitic
rhyolitic-most silica |
| What is the classification of magma based on? |
amount of silica it contains |
| Why are there diffrent types of an igneous rock |
diffrent grain sizes |
| What is fractional crystalization |
when magma cools diffirent minerals form at diffrent temperatures |
| what determines texture? |
rate of cooling determines shape of grains which is texture |
| How do you check texture? |
BY making thin slice and looking under a microscope |
| State 1 reason why igneous rocks are resources? |
minerals found in in them are resistant to weathering |
| what is most common igneous rock? |
granite |
| what is magma made of (3 things)? |
molten rock, gases, mineral crystals |
| how does silica affect magma(2 things) |
1. melting temp 2. quickly magma flows |
| HOw are Igneous rocks classified? |
extrusive and intrusive |
| What so felsic rocks look like? |
light colored, high silica content, contains quartz |
| what do mafic rocks look like? |
dark colored, lower silica content, and rich in iron and magnesium |
| Do felsic or mafic rocks have higher silica content? |
felsic |
| what size crystals form when magma cools slowly? |
large |
| what size crystals form when lava flows quickly? |
small |
Poultry
