OGT Review Day 3

Earth Science

OGT Review Day 3Topics CoveredProperties of wavesEarths CompositionChanging of Earths SurfacesGeometric TimeTheory of Tectonic PlatesGeographical Features and their Effects on ClimateEarth Science is where history meets science, and it is a constant analysis of cause and effect relationships. The focus is on the history, existence, and formation of earths geographical features.2Types of WavesMany types of energy travels in the form of a wave:- Heat- Sound- Light(Just to name a few)There are two types of waves:1.) Electromagnetic Waves2.) Mechanical WavesElectromagnetic Waves (EM Waves)Properties of Electromagnetic Waves:- Does not require a medium to travel(Medium: Any liquid, gas, or solid. Matter is another way to say medium)- Types of electromagnetic waves are listed on the ELECTROMAGNETIC SPECTRUM

Measuring Energy of EM WavesEnergy of Electromagentic waves is measured by the waves FREQUENCY

Frequency is noticable in a wave by the SPACING between waves

Space between waves is called a WAVELENGTH

Electromagnetic Spectrum

Behavior of LightWatch the following light simulationsPhoton BehaviorReflection & RefractionMechanical WavesMechanical Waves: Waves that require a medium in order to travel.

Sound is an example of a mechanical waveMedium Density and Speed of SoundSolids have a higher density than gases.Compare the spacing between the particles in solids and gases.

Predict which medium type (solid or gas) would enable sound to travel the fastest?

Medium Density and the Speed of Sound Continued

Energy of Sound WavesThe energy/intensity of sound waves is measured in two ways:1.) Frequency2.) Amplitude

In sound waves you can see AND hear the difference between frequency and amplitude.Energy of Sound Waves contObserve the following sound demonstrations and see if you can distinguish between FREQUENCY and AMPLITUDE.

Sound SimulationEarths Elements and MineralsThe Earths crust contains very few of the elements listed in the periodic table.

Earths Major Elements are as follows:Oxygen, Silicon, Aluminum, Iron, Calcium

Elements and Minerals are Earths Building BlocksMineralsA Mineral has the following properties/characteristics:- Inorganic (Not grown, naturally occuring, does not contain carbon)- Solid- Has a Crystalline structure

Physical Properties of MineralsClevage (The minerals ability to break)Hardness (Harder than glass vs. Softer than glass)Luster (Shine, how a mineral reflects light)Crystal ShapeMineral Examples and UsesExamplesUses1.) Salt

2.) Iron

3.) Quartz1.) Necessary part of human diet2.) Without iron and steel there would be no machinery3.) Used to make glass and glass fibers. Also used to make concrete, sand, and gravel.RocksThere are three primary rock types found on Earth:1.) Igneous Rock2.) Metamorphic Rock3.) Sedimentary RockRocks are constantly changing through these forms through the rock cycleRocks ContinuedRock: A naturally formed mixture containing minerals, rock fragments, or volcanic glass.

Physical Properties of Rocks:TextureCompositions (What they are made of)Igneous RocksIgneous Rocks are formed from volcanic eruptions and are a result of magma or lava.There are two types of Igneous Rocks:1.) Intrusive Igneous Rock2.) Extrusive Igneous RockIntrusive vs. ExtrusiveIntrusive Igneous RocksExtrusive Igneous RocksRocks that form WITHIN or PUSH INTO regions of Earths crust.Forms from MAGMAMAGMA and LAVA are different!MAGMA= undergroundRocks that are formed from cooled lava.LAVA IS MAGMA THAT HAS REACHED THE SURFACE

LAVA= Above ground

Sedimentary RocksSedimentary Rocks are made from bits of broken pieces of other rocks or CLASTS.These rocks go through a three step process:1.) Desposition: Weathering and erosion break other rocks into clasts and transport these pieces. These pieces lie together Loosely in this stage2.) Compaction: Gravity or compression compacts the clasts closer together.3.) Cementation: Water moves between clasts carrying minerals that can act as cement. This process solidifies the sedimentary rock.Sedimentary rocks continuedSedimentary rocks undergo one of the least Strenuous formation processes, therefore they are the rock type most likely to contain fossils.Metamorphic RocksMetamorphic Rocks: Rocks that have been changed by some combination of thermal energy, pressure, and chemical activity.

Example: Diamonds

The Rock CycleThe rock cycle diagram shows two things:1.) How each rock is formed2.) How each rock can change

Rock Cycle Diagram

WeatheringWeathering: The process of physical or chemical breakdown of a material at or near Earths surface.There are Two Types of Weathering:1.) Mechanical Weathering: Turning big pieces into smaller pieces.2.) Chemical Weathering: Forms and releases new compounds.Benefits of Chemical WeatheringChemical weathering is a process that releases new compounds.These compounds help enrich soil and nourish plants. Without this process we wouldnt have topsoil for plants, Terrestrial Ecosystems (Terrestrial means rocky/earth), and humansErosionErosion: The removal of surface material through the processes of weathering.Think of this process as an Earth Shaping Factory-Weathering is responsible for breaking down materials and producing nourishing compounds-Erosion is responsible for transporting and depositing these materialsGeologic TimeScientists are able to infer a great deal of information from the study of rock layers and earth samples.Absolute Dating: Assigning precise numeric age to an organism, object, or event.- Example: Joey is 18 years, 21 Days, 2 Hours, and 32 Minutes old.Relative Dating: Process of putting objects in order in sequence of when they happened.- Example: This rock layer existed first, this rock layer came second, the next layer came third, etc.

Principles of Relative DatingPrinciple of Superposition: States that the oldest rock layer is on bottom and the newest layer is on top.Unconformities: Gaps in in the rock when erosion was present or deposition was absentEither things were taken away (erosion) or nothing was added (deposition)

Principle of Superposition and Unconformity

Absolute DatingIn order to figure specific numeric dates scientists use the ratios between radioactive isotopes and their stable daughter to calculate the number of years passed. This is the use of Radioactive DecayAtom SimulationDemonstrate Carbon-14 Dating 6 Protons, 6 Electrons, 8 Neutrons Transforms into Stable Daughter Nitrogen-14 (Add a Proton)32Half-LifeEvery radioactive isotope has a half-life.The half life for the isotope pair Radioactive Isotope: Carbon-14 and its Stable Daughter: Nitrogen-14 is 5,730 yearsThis means when a geoligists analyzes this pair and they see that the atom is 50:50 (Half of the radioactive isotope and half of the stable daughter) the sample is 5,730 years old.Theory of Tectonic PlatesPlates are composed of a rigid uppermost mantle and a layer of either Oceanic Crust or Continental Crust above.There are 3 main kinds of plate motions:1.) Divergent2.) Convergent3.) TransformPlate Tectonics Simulation

Boundaries and FeaturesPlate MotionGeographic Feature Created1.) Divergent Boundaries: Spread apart

2.) Convergent Boundaries: Plates collide or push together

3.) Transform Boundaries: When plates rub together1.) Create rift valleys and ocean basins

2.) Create Volcanoes, Mountains, and deep trenches

3.) Creates faultsSubduction and VolcanoesVolcanoes form when a thick Continental Lithosphere converges or collides with thinner Oceanic LithosphereThis results in the Oceanic Lithosphere moving under the Continental lithosphere. THIS IS CALLED SUBDUCTIONPlate MotionThe driving force for all mechanisms in plate motion is INTERNAL CONVECTION OF MANTLE MATERIAL.

Convection vs. ConductionConvectionConductionBoth are methods of heat transfer

Convection is the transfer of heat through liquid and air

Warm air rises cool air is lower, this is how heat is transferedThis is a transfer of heat through a solid.

The heat in a soild will travel towards the cooles part of an object

Thats why you dont want to stir boiling water with an all metal spoon. (OUCH!)Geographic Features Effects on ClimateVarious features on Earth affect the climate experienced in that area

Compare the conditions of a location near mountains vs. a location near a lake (or any body of water)Mountains and their Effects on ClimateAreas with mountains typically experience arid (Dry) to semi-arid (Semi-dry) conditions, because they block the moisture from bodies of water.Bodies of Water Affect on WeatherPlaces located by water experience the following conditions:Increased moisture content in the air and soil Prolonged time without frostLake effect snowPractice Test QuestionsComplete the practice test questions written on the board.

We will go over these once you finish.