Transcript Rocks and soil

Rocks
and Soil
Rocks
• ROCKS
• The rocks you see around you - the mountains,
canyons & riverbeds, are all made of minerals.
A rock is made up of 2 or more minerals.
Think of a chocolate chip cookie as a rock.
The cookie is made of flour, butter, sugar &
chocolate.
The cookie is like a rock and the flour, butter, sugar
& chocolate are like minerals.
You need minerals to make rocks, but you don't need
rocks to make minerals.
All rocks are made of minerals.
Rocks
• Properties of Rocks (how we categorize
them)
•
Texture
•
Layering
•
Color
Texture
• How smooth or rough they are
• http://www.classzone.com/books/earth_sci
ence/terc/content/investigations/es0603/es
0603page02.cfm
Layering
• http://www.clas
szone.com/boo
ks/earth_scienc
e/terc/content/in
vestigations/es
0610/es0610pa
ge04.cfm
3 types of rocks
• Igneous Rocks
• Metamorphic Rocks
• Sedimentary Rocks
Igneous Rocks
• Igneous rocks form directly
from the cooling of magma.
• http://www.fi.edu/fellows/fellow1/oct98/cre
ate/igneous.htm
Metamorphic Rocks
• The metamorphic rock gets the name from
"meta" (change) and "morph" (form).
• The rock is moved into an environment in
which the minerals which make up the
rock become unstable. In most cases, this
involves burial which leads to a rise in
temperature and pressure.
• http://www.fi.edu/fellows/fellow1/oct98/create/me
tamorph.htm
Sedimentary Rocks
• In most places on the surface, the
igneous rocks which make up the
majority of the crust are covered by a
thin layer of loose sediment, and the
rock which is made as layers of this
debris get compacted and
cemented together.
• http://www.fi.edu/fellows/fellow1/oct98/cre
ate/sediment.htm
Rock Cycle
• http://www.classzone.com/books/earth_sci
ence/terc/content/investigations/es0602/es
0602page02.cfm
Smaller rocks come
from the breakdown of
larger rocks through
the action of plants
and weathering
Soil
Composition
• Soil is made of:
–Small rocks
–Decomposed pieces of plants and
animals
• Dead plants
• Dead animals
–Products of plants and animals
• Animal waste
Properties of Soil
• Color
–Is it dark or light?
• Capacity to retain water
–Does it hold a lot of water?
• Capacity to grow plants
–Does the soil have nutrients like
nitrogen to help plants grow well?
• Texture
–How does it feel?
Kind of soil How it feels
Hold shape
when wet
Sandy
Feels gritty
Silty
Feels powdery
Clay
Feels sticky
Won’t stick
together when
wet
Will stick
together when
wet but will not
hold together
after it dries
Stays together
when wet
Which is clay? Which is
sand?
• Soil is also
found in layers
like rocks, with
topsoil on top.
• Each layer is
called a
horizon
• http://www.classzone.co
m/books/earth_science/t
erc/content/investigation
s/es1206/es1206page02
.cfm?chapter_no=investi
gation