CHEMISTRY - The Earth (1)

MANTLE

• Mostly solid rock

• Rock flows freely

• Largest layer of the earth

• Hot rock rises, cool rock sinks

EXTRUSIVE ROCKS

• Igneous rocks

• Formed overground

• Crystals smaller than that of intrusive rocks

• When lava freezes and particles arrange into crystals

UPLIFT

Movement of the Earth’s crust, causing landmasses to collide and pushing rock upwards – mountains

DEPOSITION

The settling of sediments after weathering & transportation (erosion)

COMPACTION

When layers of sediment above squash those below, causing them to compact into sedimentary rock

CEMENTATION

When a substance causes grains of sediment to stick together

TRANSPORTATION

the movement of sediment far away from the original rock

IGNEOUS ROCKS

• Formed when liquid rock cools and freezes, particles arranging into crystals

• Hard & Durable

• Non-porous (except for pumice)

• Crystals

Examples of IGNEOUS ROCKS

• Granite

• Basalt

• Pumice

METAMORPHIC ROCKS

• Formed due to existing rock experiencing heat or high pressure

• Crystal

• Non-porous

Examples of METAMORPHIC ROCKS

• Marble

• Slate

CORE

• Split into outer and inner

• Made up of iron and nickel

• Outer is liquid

• Inner is solid

SEDIMENTARY ROCKS

• Grainy

• Soft

• Porous

Examples of SEDIMENTARY ROCKS

• Chalk

• Limestone

• Sandstone

WEATHERING

The breaking up of a rock into sediments

FREEZE-THAW WEATHERING

Water seeps into a crack in a rock, freezes when the temperature drops, and widens the crack. After repeating this, the rock will finally split in two

CHEMICAL WEATHERING

When acids in rain react with substances in a rock to break it

BIOLOGICAL WEATHERING

When flora or fauna break up a rock

THREE types of WEATHERING

• Freeze-Thaw

• Chemical

• Biological

EROSION

The breaking of rocks into pieces of sediment, and then their movement away

ATMOSPHERE

A mixture of gases that surround the earth

TROPOSPHERE

The closest part of the atmosphere to earth, around 10km above the surface

FOUR steps in the formation of a SEDIMENTARY ROCK

• Weathering

• Transportation

• Deposition

• Compaction / Cementation

FIVE most common ELEMENTS in the CRUST

• Oxygen 46.4%

• Silicon 28.2%

• Aluminium 8.3%

• Iron 5.6%

• Calcium 4.2%

ROCK CYCLE

The processes that change one rock to another, and how they interlink in the rock cycle