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the solid, outer layer of the earth that consists of the crust and the rigid upper part of the mantle


A naturally occurring solid mixture of one or more minerals or organic matter

Rock Cycle

sequence of events in which rocks are formed, destroyed, altered, and reformed by geological processes (a process where one rock type changes into another).


Inorganic crystalline substances found naturally in the earth.

Sedimentary Rock

A type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together

Igneous rock

A type of rock that forms from the cooling of molten rock at or below the surface.

Metamorphic Rock

A type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions

Intrusive Rock

Igneous rock that forms when magma hardens beneath Earth's surface.

Extrusive Rock

Igneous rock that forms from lava on Earth's surface


characteristics used to describe a substance

Mohs Hardness Scale

a scale ranking ten minerals from softest to hardest; used in testing the hardness of minerals


the way a mineral reflects light from its surface


The color of the powder left when a mineral is rubbed against a hard rough surface


The process by which natural forces break down rocks and minerals.


The process by which wind, water, ice, or gravity transports soil and sediment from one location to another


Solid materials such as rock fragments, plant and animal remains, or minerals that are carried by water, wind, ice, gravity, or some other natural force and settle in a new location (bottom of a body of water or at the foot of hills and mountains)


process in which sediment is laid down in new locations


Molten rock beneath the planet's surface.


Molten rock that reaches a planet's surface through a volcano or other opening in the crust


physical property of some minerals that causes them to break along smooth, flat surfaces

Crustal Deformation

The bending, tilting, and breaking of the Earth's crust caused mainly by movement of the tectonic plates.

Destructive forces

Forces that wear away or break down land masses on the earth's surface (weathering and erosion)

Constructive forces

Forces that shape Earth's surface by building mountains and landmasses

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