NOTES: Soil 
 
Soil is made up of rock and decayed plants and animals. 
-It provides nutrients for plants to grow. 
 
How soil is formed: 
-Mechanical weathering breaks down rocks into small pieces. 
-Chemical weathering further breaks down the rock when tiny organisms (bacteria & fungi) produce acids. 
-The rock breaks down into minerals needed by organisms. 
-Small plants begin to take hold of the new soil. They grow and eventually die. 
-Bacteria and fungi decay the dead plants. 
-The decayed plant material is now organic material (humus) that becomes part of the soil. 
 
Soil Profile 
-The 3 layers, or horizons, of soil make up the soil profile. 
-Mature soil develops over thousands of years. 
 
 
 
A Horizon – TOPSOIL – nutrient-rich, dark soil where roots of plants grow and worms and insects live. 
B Horizon – SUBSOIL – mostly clay and minerals, some very deep plant roots, and some nutrients carried by water from the topsoil. 
C Horizon – mostly weathered rock, very little nutrient carried from the subsoil by water. 
 
BEDROCK – solid, un-weathered rock below the C Horizon of the soil profile. 
 
 

Posted by: Lindsay Hook

NOTES: Processes of Change 
 
Two main processes that change the Earth’s surface: weathering & erosion 
 
Weathering: slow wearing-away or breaking down of objects exposed to Earth’s atmosphere & water 
-Mechanical weathering: objects are broken into small pieces but the chemical composition of the object does not change. 
-example: the sphinx 
-changes in temperature cause objects to expand/contract, causing cracks 
-Chemical weathering: when an objects chemical makeup changes due to chemicals in the atmosphere 
-example: metal rusts when left outside because water and causes an oxidization reaction 
-chemicals released into the atmosphere condense into clouds and fall back to Earth as acid rain, which causes metal to change color and rock to be destroyed. 
Example: The Statue of Liberty is copper but has turned green from the acid rain reacting with the copper 
 
Erosion: moving of materials from one place to another by nature 
-example: Grand Canyon (where river used to flow is now a canyon b/c the rushing water carried pieces of rock away) 
-landslide: mud, rock, or dirt is pulled down a hill by gravity 
-Deposition: the building up of land by erosion 
-example: sand dunes are built up when wind carries the sand to a new location 
-Erosion can occur by rain, wind, gravity, glaciers, waves, water, hurricanes, etc. 
 
 

Posted by: Lindsay Hook

NOTES: Lithospheric Plates 
 
-The lithosphere is the solid outer layer of Earth. 
-It includes the crust and the top part of the mantle 
-Moving chunks of the lithosphere are called lithospheric plates 
-In 1912, a scientist named Wegener noticed that the continents were shaped like puzzle pieces that could fit together. 
-Wegener propsed the idea of continental drift, which means the continents were once connected and have since broken apart and drifted to their current locations. 
-Not many people believed in Wegener’s hypothesis until evidence was found to support it. 
-Some things that supported continental drift:  
-Fossils: remains or signs left behing by a once-living thing 
-Mesosaurus: freshwater reptile that lived 250 million years ago, found in both South America and Africa. 
-Same mountains and rocks on the east cost of S. America and the west coast of Africa 
-Movement of continents is about 2 cm per year 
-Continental plates are less dense than oceanic plates 
-When continental and oceanic plates collide, the oceanic plate subducts underneath the continental plate. 
-Where they collide, magma can rise and cause volcanoes to erupt (ex.: Mt. St. Helens) 
-When 2 oceanic plates collide, one slides under the other. This can form deep trenches or islands (ex.: Aleutian Islands) 
-When 2 continental plates collide, they both buckle upward. This forms mountains.  
-Sometimes continental plates that are stuck against each other become unstuck, causing an earthquake. 
-The Ring of Fire is the line of plate boundaries in the Pacific Ocean made up of a belt where volcanoes and earthquakes are really common. 
 

Posted by: Lindsay Hook

fossil - remnant of an organism 
 
Types of fossils: 
 
body fossil- part of the organism that has been preserved 
-very rare 
-occurs in extreme conditions like desert, tar pits, or snow 
 
trace fossils- impression left behind by an organism, such as animal tracks, nests, bit marks, or animal poop 
-most common type of fossil 
 
mold fossil - hollow print left behind when animal/plant is buried quickly and then decays 
 
cast fossil - occurs when minerals fill a mold fossil and then harden to become rock 
-the fossil looks identical to the original organism 
 
Other information 
 
fossil fuel - oil, gas, and coal formed from the remains of living organisms 
 
fossil record - the sum total of everything known about fossils 
 

Posted by: Lindsay Hook

BrainPop: Crystals 
 
-salt, sugar, and baking soda are examples of crystals 
-crystal: solid whose molecules are arranged in an ordered, repeating pattern 
-any mineral with a geometric shape is a crystal 
-most solids are made up of crystals 
-Crystals can be made from different elements 
Examples: diamond=carbon; salt=sodium and chlorine 
-Crystal color depends on what elements are mixed in 
-Crystal shape depends on how the elements group themselves 
-Crystals grow in organized geometric shapes called the crystal lattice 
-There are 7 main types of crystals: 
1. isometric 
2. trigonal 
3. hexagonal 
4. tetragonal 
5. orthorhombic 
6. monoclinic 
7. triclinic 
-We use x-rays to determine crystal shape 
-Liquid crystals exist as gels (example: calculator) 
 
 

Posted by: Lindsay Hook

BrainPop: Mineral Identification 02/05/08 
 
Physical properties tell minerals apart. 
-Color: first indicator 
-Hardness: how easily a mineral is scratched 
*Mohs scale ranks hardness of minerals 
-Luster: how light reflects off a mineral 
-Streak: powder color of a mineral 
-Cleavage: when a mineral breaks along a flat (smooth) surface 
-Fracture: when a mineral breaks along a jagged (rough) edge 
 

Posted by: Lindsay Hook

What is a mineral? 
-A mineral is a compound made up of one or more elements. 
-A mineral forms naturally (it is not man-made). 
-A mineral is made of materials that were never alive. 
-Minerals have the same chemical makeup (they are made of the same compounds) no matter where they are found. 
-Minerals have atoms arranged in regular patterns and form solid units called crystals. 
-There are about 2,000 different known minerals. 
-Examples of minerals: 
Gold (Au) 
Sulphur (S) 
Aluminum (Fe) 
Copper (Cu) 
Iron (Fe) 
Halite (NaCl) 
Graphite (C) 
Galena  
Azurite 
Malachite 
Mica 
Quartz 
 
What is NOT a mineral? 
-Anything that contains material from a once-living organism. This includes fossil fuels like coal and petroleum, and coral or pearls. 
-Anything that contains more than one mineral is called a rock. 
 
Minerals are recognized by their common characteristics: 
 
Color – Some minerals can be many different colors, but others are always the same color. For example, sulfur is yellow. 
Luster – The amount of light reflected from the surface of a mineral. Can be glassy, metallic, shiny, dull, waxy, satiny, or greasy. 
Streak – Some minerals leave a colored streak when you “write” with them on an unglazed white tile. This may not be the same as the mineral’s color. Hematite is usually gray, but its streak is always reddish. 
Texture – The feel of the mineral when it is rubbed. can be rough, smooth, bumpy, or soapy. 
Hardness – Some minerals can be scratched more easily than others. We use the Mohs’ Hardness Scale of 1-10 to determine what material will or will not scratch the surface of a mineral. 
Cleavage – This is the angle at which a mineral breaks. Some minerals have no cleavage, and just break into rough pieces. This is called fracture. Others break into specific shapes, like flat sheets or cubes. 
Other properties – Some minerals may be magnetic, which can be tested by trying to stick a small magnet to the sample. Other minerals may bubble when exposed to hydrochloric acid (HCl).  

Posted by: Lindsay Hook

SEVERE WEATHER NOTES 
 
The boundary where high pressure and low pressure meet is called a front. These usually produce precipitation. 
 
Thunderstorms 
• Form within cumulonimbus clouds 
• Happens when warm air is pushed upward at a cold front 
• Can also happen on hot, humid days 
• Produce heavy rain and sometimes hail 
• It takes about 30 minutes for a cloud to turn into a thunderstorm 
 
Lightning 
• Occurs when condensation releases energy that charges the atmosphere 
• The difference between charges causes lightning 
 
Tornadoes 
• Develop in cumulonimbus clouds under the same conditions as thunderstorms. 
• Warm, moist air meets cold, dry air 
 
Hurricanes 
• Form in low pressure areas over large areas of warm tropical waters 
• Usually from June to November 
• Energy from warm, humid air at the ocean’s surface makes air pressure increase 
• Winds move inward towards the low pressure areas 
• The lower the pressure, the faster the spin 
• Wind speeds must reach 74 mph to achieve hurricane status 
• We call this type of storm a hurricane if it occurs in the Atlantic Ocean, but it is called a typhoon if it occurs in the Pacific Ocean. 
• Hurricanes can’t travel over land because they are fueled by water 
• Each year, about 10 low pressure systems form. Of these, 6 become hurricanes, and 2 of those are huge storms that create extensive damage. 
• Hurricane Naming: 
o Originally named based on latitude and longitude 
o In WWII, pilots named hurricanes after their wives or girlfriends 
o 1950s: US Weather Service used alphabetical female names 
o 1970s: used both male and female names (current system) 
• 6 year rotation of name lists 
• names are retired if the storm results in severe damage 
 

Posted by: Lindsay Hook

States of Matter 
 
 

Posted by: Lindsay Hook
Podcast: states of matter notes image.jpg

HEAT NOTES  
 
Heat is the total energy of the motion of molecules in a substance. 
-Heat depends on the size or number of particles, the speed of the particles, and the type of particles 
-Heat is energy! 
 
Temperature is the average energy of the motion of molecules in a substance 
-Temperature does NOT depend on the size, number, or type of particles, only on the speed at which the particles are moving 
-Temperature is a measure of energy 
 
Types of Heat Transfer 
 
1. Conduction – heat transfer from molecule to molecule (two substances touching) 
• Heat is transferred from the warmer object to the cooler object 
• If something feels cold, it is because the heat is going from you to the substance 
• Example: When you touch a cup of hot coffee, the heat in the molecules of the coffee mug is transferred to the molecules in your hands. 
 
2. Convection – heat transfer by the circulation of rising warm air and sinking cool air 
• Warm, moist air forms convection currents better than warm dry air. (This is why more severe weather occurs in the warmer months.) 
• Convection currents form when more dense, cool air forces lighter, warmer air to rise. 
• Moist air (or humid air) holds heat better than dry air, which is why it feels hotter in humid climates and why running a humidifier or vaporizer seems to make a room feel warmer. 
 
3. Radiation – heat transferred by infared waves 
• Infared waves are next to the color red on the light spectrum. They give us heat. 
• Radiation is also called radiant heat 
• Light colored clothes reflect heat, and dark colored clothes absorb heat. 
• Example: When you warm up next to a fire, you are experiencing heat by radiation. 
• When your car gets hot after sitting in the sun, this is heat transfer by radiation. 
 
BrainPop Notes 
 
1. Energy causes molecules to become active/excited. 
2. In this excited state, molecules move around and bump into each other a lot. 
3. Temperature measures how fast molecules are moving. 
4. Heat measures the energy contained within an object because of its moving molecules. 
5. There is more heat in an iceberg than in a pot of boiling water. 
6. This is because the iceberg is a lot bigger. 
7. The lowest temperature you can get is absolute zero or -273°C. (This is the temperature at which all molecular motion stops.) 
8. Heating up an object causes it to expand because excited molecules take up more space. 
 

Posted by: Lindsay Hook

Cloud Notes 
 
How clouds form: 
-Energy from the Sun turns liquid water in oceans, lakes, river, etc. into water vapor 
-Water vapor rises into the air 
-The water vapor eventually reaches cool air 
-The cool air makes the water vapor condense, or clump together 
-The condensed water is a visible cloud 
 
Types of clouds: 
Stratus: low, indicates fair weather, rain, or snow. Layered…the kind of clouds when the whole sky appears covered with a dull cloudy mass. 
-fog: stratus clouds near the ground 
-altostratus: low to middle clouds, sun peeks through 
-nimbostratus: layered cloud indicating rain or snow 
Cumulus: puffy white clouds with flat bases; high up in atmosphere; indicate fair weather or thunderstorms. 
-cumulonimbus: puffy, gray, towering thunderstorm clouds 
Cirrus: high, feathery, white clouds made of ice crystals that usually indicate fair weather or rain 
-cirrostratus: high clouds – fair or stormy weather 

Posted by: Lindsay Hook

THE WATER CYCLE  
NOTES 
 
• hydrosphere - term that refers to all the water on Earth’s surface. 
 
• The water cycle : water moving continuously between the hydrosphere and the atmosphere. 
 
• The sun drives the water cycle by giving off the heat energy that causes water to evaporate and enter the water cycle. 
 
Important Terms: The number for each term corresponds to the matching item on the diagram (below). 
 
5- cloud: collection of water droplets or ice crystals in the air 
 
14 - collection: when precipitation or runoff enters a body of water 
 
4 - condensation: when water vapor cools and changes back into a liquid 
 
2 - evaporation: when liquid water is heated and changes into water vapor 
 
12 - groundwater: water that soaks into the Earth and collects in empty spaces (drinking water/well water) 
 
6 - ice crystals: frozen water droplets (solid) 
 
10 - percolation: when water seeps into the soil 
 
8 - precipitation: water that falls back to Earth as rain, snow, sleet, or hail 
 
1 - radiation: heat energy from the sun 
 
11 - runoff: water that does not soak into the ground and flows over Earth’s surface 
 
9 - sublimation: frozen water (ice/snow) changes directly into water vapor (gas)  
without becoming a liquid 
 
13 - transpiration: water vapor is released from the leaves of green plants into the air 
 
7 - water droplets: water that has condensed into a liquid 
 
3 - water vapor: water in a gas state in the atmosphere 
 
 
 

Posted by: Lindsay Hook
Podcast: water cycle drawing.jpg

Earth’s Atmosphere Notes 
 
Atmosphere is made up of a mixture of gases – mostly nitrogen and oxygen 
- wraps around Earth like a blanket 
- could not live here without it 
- gases protect us from sun's dangerous rays 
- perfect habitat for plants and animals 
 
There are 5 layers: 
 
1. Troposphere - lowest - weather layer (rain, snow, wind) 16 km at equator, 8 km at poles 
 
2. Stratosphere- top of troposphere to 50 km above ground 
- temperature increases with altitude  
- (-60 degrees C) at bottom warms to about freezing 
- heated from above by sun’s ultraviolet radiation 
- ozone - gas that absorbs harmful UV rays and protects us from solar radiation 
- pollution created a hole over the South Pole 
 
3. Mesosphere - 50 km above ground 
- coldest temperature (-90 degrees) 
- lots of meteors disintegrate from friction 
 
4. Thermosphere - hottest layer 
- thin air, not much solar radiation can be absorbed  
- 2000 degrees C 
- ionosphere found here 
- filled with charged particles 
 
5. Exosphere - 500 km above Earth 
- highest level of atmosphere 
- not stable; very thin, gas molecules can escape into space 
 
 
 
Why is the sky blue? 
- light has different colors based on wavelength 
- gases scatter certain wavelengths of light, lets others pass through 
- blue light scattered most efficiently, why sky appears blue 
- color of light that gets through our atmosphere most  
 
Click here for a great website on the atmosphere! 

Posted by: Lindsay Hook

Climate & Weather Notes 
 
"Climate is what we expect; weather is what we get." - Mark Twain 
 
Weather: process in atmosphere that changes over short periods of time 
 
Climate: weather that is in a place most of the time, or for a long period of time 
 
GA: Climate is warm and moist 
AZ: Climate is hot and dry 
 
Visible light: sun’s energy you can see 
 
Invisible light: sun’s energy you cannot see – UV (ultraviolet) rays 
-heats up the Earth’s clouds, air, oceans, land 
 
-Land heats up and cools down faster than water 
-Water heats up slowly but holds heat longer 
-Warm air is less dense, so it rises 
-Air that is over water stays cooler. It sweeps over land and replaces warm air. This is called a sea breeze. 
-When cooler air over a continent replaces warm ocean air, it is called a land breeze. 
-Convection currents: up and down movements that transfer heat from one place to another 
-air masses: chunks of warm or cold air that move sideways across continents or oceans. 

Posted by: Lindsay Hook

TIDES NOTES 
 
Tide (definition): the rise and fall of the ocean surface caused by the interaction of gravity between the sun, moon, and earth. 
 
• Tides are giant waves. They are not very high (only 3-6 feet), but they are very long – thousands of kilometers!  
 
• Tides are sometimes referred to as a "bulge" in the ocean. The part of the ocean (in line with the moon) that bulges out is a high tide; the part of the ocean that is not in line with the moon and does not bulge is a low tide. 
 
• Tides are MOSTLY caused by the gravitational pull of the moon. 
 
• Tides are also affected by the sun's gravity. This makes the moon’s pull on Earth stronger or weaker. 
 
• At high tide, the ocean water has risen as high as it will go on shore. 
 
• At low tide, the ocean water has fallen as low as it can go on shore. 
 
• Earth’s rotation on its axis affects which tides will occur at a certain place on Earth and when tides will occur. 
 
• High tides occur about every 12 hours. There are 6 hours between high and low tide in most places. 
 
• When the sun, moon, and Earth are in a line, we get especially high tides called spring tides. This occurs only during a full moon or a new moon. 
 
 
 
• When the moon is at a right angle (L-shape) to the sun, we get neap tides. 
This occurs only during first or last quarter lunar phases. 
 
 
 
See links on the Tides Webquest for more information! 

Posted by: Lindsay Hook