Igneous rock Flashcards
Igneous rock composition
Felsic - high feldspar
Intermediate - between Felsic and Mafic
Mafic - high magnesium and iron
Ultramafic
Granite (common Felsic igneous)
Coarse grain intrusive rock
Rhyolite (common Felsic igneous)
Fine grained extrusive rock
Obsidian (common Felsic igneous)
Volcanic glass
Cools quickly - no time for crystals to grow
Pumice (common Felsic igneous)
Forms when large amounts of gas escape from molten rock to generate a gray, frothy mass; most samples of pumice float in water
Andesite (common Intermediate igneous)
Medium gray extrusive rock
Diorite (common Intermediate igneous)
Medium gray intrusive rock
Basalt (Common Mafic igneous rock)
Fine grained, extrusive rock
Gabbro
Coarse grained, intrusive rock
Sedimentary rock
Formed by the lithification of sediments (pressure and time)
Detrital (Clastic)
Lithification of sediments that originated as solid particles from weathered rocks
Particle size used to distinguish detrital sedimentary rocks
Conglomerate
Composed of rounded gravel size particles
Breccia
Composed of angular gravel sized particles
Sandstone
Composed of sand
Siltstone
Composed of silt
Does not break layer
Arkose
Sandstone that contains more than 25 percent of feldspar
Chemical
Derived from ions carried in solution to lakers and seas - ions then precipitate out of solution
Organic
Lignite coal and Bituminous coal
Metamorphic rock
Produced from preexisting rock igneous, sedimentary, or other metamorphic rocks
Every metamorphic rock has a parent rock - the rock from which it was formed
Occurs most often when rock is subjected to a significant increase in temperature and pressure
Low grade metamorphism
Low temps and pressure
High grade metamorphism
High temps and pressure
Non foliated metamorphism
A result of contact metamorphism
Diorite
Formed by the slow cooling underground of magma
Sulfur
Nonmetallic chemical element belonging to the oxygen group
Gypsum
Calcium sulfate
