rocks
nyashia gaines: igneous, sedimentary, and metamorphic
rocks:
rocks are made of crystals, they are classified by the way they are formed.
igneous
igneous rocks are formed by melting and solidification of magma. they are formed inside or outside a volcano. the main types of igneous rocks are intrusive which cool slowly and forms large crystals and extrusive cools quickly at the surface forming small crystals.
sedimentary
sedimentary rocks are formed by compaction and cemented minerals. they are formed by being compacted with particles they are formed with weathering and erosion. the main types are clastic that are pebbles, cobbles and/ or boulders embedded in the sand, slit, or clay. crystalline forms crystals from chemical precipitates and evaporites. bioclastic is compacted plant remains.
metamorphic
metamorphic rocks are formed with heat and pressure, they are formed deep within the earths surface. the main types are foliated which are thin layers on top of each other creating a pattern. non- foliated rocks don't have layers or bands.
igneous rock : granite
-crystals formed fast
-course
-non-vesicular
-dark, low density, and felsic
-20% amphilbole
-16% biotite
-45% plagioclase feldspar
-40% quartz
-75% potass
sedimentary rock : rock salt
-chemically formed
-fine to course
-crystalline
also rock salt is composed of halite.
metamorphic rock : quartzite
-non-foliated
-fine to course
-composition is quartz
-regional or contact
quartzite is a metamorphism of quartz sandstone.
the rock cycle !
rocks are created and destroyed in cycles. it show how rocks are formed, how they break apart and form into other rocks over time. the three types of rocks igneous, sedimentary, and metamorphic are the results of the formations that are all made up of minerals.