igneous rocks Flashcards
WHAT DOES RAPID COOLING OF LAVA RESULT IN
fine-grained rocks with a distinctive structure
what happens when magma reaches the surface
cooling occurs rapidly as lava comes in contact with water or air
what is glass
a rock with few or none mineral membrane crystals
what is obsidian an example of
volcanic glass
what is a pumice
a glass which contains holes(vesicles) where gas bubbles are trapped giving it bo0uyancy
what is the most common extrusive igneous rock
basalt(forms most of the seafloor)
decompression melting
melting by changing pressure
flux melting
melting throught the addition of water to the earths mantle
what are 2 general properties that are useful in identifying rocks
texture and mineral compression
what does texture refer to
size shape and arrangment of the mineral crystals
what is mineral composition
the minerals that comprise the rocks
