Chapter 4-1 Main Ideas • Describe how rocks have been used by humans. • Describe the 4 processes that shape Earth’s features.
Key Vocabulary • Rock – a naturally occurring solid mixture of one or more minerals/organic matter. • early uses for rocks included tools & weapons.
Key Vocabulary • Rock Cycle – the continuous process by which new rock forms from old rock material. • Weathering – the process in which wind, water, ice, heat, & gravity break down rock
Key Vocabulary • Erosion – the process by which sediment is removed from its source.
Key Vocabulary • Deposition – the process by which sediment, moved by erosion is dropped and comes to rest. • Sediment – rock, mineral fragments.
Key Vocabulary • Uplift – is movement within the Earth that causes rocks inside the Earth to be moved to the Earth’s surface. - When uplifted rock reaches Earth’s surface, erosion, weathering, & deposition begin.
Key Vocabulary • Composition – the minerals that a rock contains; the chemical makeup of rock. • Texture – the size, shape, & positions of the grains that make up a rock.
Types of Rocks • Igneous • Sedimentary • Metamorphic
Igneous Rock • Formed when magma cools • Inside the Earth • Can be heated under pressure • Becomes metamorphic rock • Can be melted again to form new magma -- Becomes igneous rock • Above the ground • Can be weathered and eroded • Becomes sedimentary rock
Sedimentary Rock • Formed when sediments compact & cement into layers • Inside the Earth • Can be heated under pressure to form metamorphic rock • Above the ground • Can be weathered again to form more new sediment • Inside the Earth • Can be melted again to form new magma igneous rock
Metamorphic Rock • Formed when rock changes under heat & pressure • Inside the Earth • May melt to form magma igneous rock • Above the ground • May weather & erode to form sediment • Inside the Earth • Can be heated under pressure to form metamorphic rock