LESSON 2.2 : The Rock Cycle

rock

naturally-occurring, coherent aggregate of minerals or solid materials; composed of the crust and outermost part of the upper mantle

lithosphere

from Greek word “lithos” → stone

rock cycle

model that describes all the processes by which rocks are formed, modified, transported, decomposed, melted and reformed

melting

forms magma

cooling/crystallization

forms igneous rock

erosion or weathering

forms sediment

compaction and cementation

forms sedimentary rock

heat and pressure

forms metamorphic rock

magma

all rocks can melt and turn into ___

sediment

weathering/erosion affects all rock types to produce ___

metamorphic rock

heat and pressure can alter any existing rock into ___

igneous rocks

formed from solidified molten rock material; dependent on the location and speed of cooling

extrusive/volcanic

igneous rocks that cool quickly at earth’s surface from lava

intrusive/plutonic rocks

igneous rocks that cool slowly beneath earth’s surface from magma

weathering/erosion

breakdown of rocks into small particles by natural forces, or the movement of those particles

sediment

small particles of rock, minerals, or organic material produced by weathering and erosion

compaction

process where sediments are pressed together under pressure from overlying layers

cementation

process where minerals bind sediment grains together to form solid rock

lithification

overall process of converting loose sediments into solid rock through compaction and cementation

sedimentary rocks

rocks formed from sediments through lithification; characterized by distinct layers

bedding

distinct layers formed during the deposition of sedimentary rocks

organic

sedimentary rocks formed from the lithified remains of plants and animals

chemical precipitate

sedimentary rocks formed from dissolved minerals that precipitate out of solution and lithify

metamorphism

the process where pre-existing rocks are altered by heat, pressure, and fluid chemical activity

metamorphic rocks

rocks formed when existing rocks are altered by metamorphism

non-foliated

absence of platy surfaces or wavy alignment of minerals

foliated

layered or banded appearance in rocks