Three Kinds of Rock
These are rocks formed when lava or magma cools down and hardens.
These are made from the smallest particles of rock.
Clay
This is the process of breaking rocks into smaller pieces; caused by wind, rain, water, frost, ice, temperature changes, and chemical changes.
Weathering
This is the loose top layer of the Earth’s surface; a mixture of rocks, sediment, and organic matter.
Soil
Here, there are fewer living things, and, as a result, less humus.
Subsoil
These are rocks formed out of sediment, or pieces of rocks, minerals, and fossils.
Sedimentary rocks.
These are particles of rock that are larger than clay particles and smaller than sand particles.
Silt
This is the movement of rock and sediment by water, ice, wind, and gravity.
Erosion
This is completely decayed organic matter found in most soils; decomposed plant and animal matter.
Humus
The lowest layer of soil is this. Here, we have loose rock and clay with no humus.
Rock layer
This is any rock changed to a new rock by heat and pressure without melting.
Metamorphic
These are particles of rock that are larger than clay and silt particles, and smaller than pebbles; large enough to see.
Sand
This is the breaking apart of rocks caused by wind, water, ice, or cold.
Physical weathering
Name all layers of soil, from top to bottom.
Organic, topsoil, subsoil, rock
Below the rock layer lies this solid rock.
Bedrock.
These are loose particles of rocks and minerals, such as clay, silt, sand, pieces of shells, or a mixture of these; deposited by wind, water, or ice.
Sediment
How does silt feel?
Soft, smooth, and silky.
This is when chemical reactions cause rocks to dissolve.
Chemical weathering.
This layer of soil is made of organic material, namely twigs, leaves, and decaying organic matter.
Organic
Is all soil the same?
No
These are the remains of plants and animals that are preserved in sedimentary rock.
How does sand feel?
Gritty
Name one natural force that can cause erosion.
Ice, water, gravity, or wind
This is a mix of humus and sediment. Worms, insects, moles, and groundhogs live here.
Topsoil
Name the rock with the largest pieces
Sand