Earth’s History Ms. Yewande 8th Grade Science
Warm-up:Write questions and answers in notebook. • What is the first thing a student should do if an accident happens during a science experiment? • Report to the teacher • Clean the laboratory station • Locate the nearest exit • Put on safety goggles
Warm-up:Write questions and answers in notebook. • Which device is used to determine the volume of a liquid? • Anemometer • Graduated cylinder • Test tube • Thermometer
Lab Safety Safety Rules: • Always wear safety goggles whenever you are working with chemicals or other substances that might get into your eyes. • Never reach across a flame. • Immediately notify your teacher if any chemical gets on your skin or clothing to find out what to do to clean it off. • Never look directly into a test tube when mixing or heating chemicals. • Always point a test tube away from you and others when heating it over a flame or other heat source.
Lab Safety Safety Rules: • Never smell a chemical directly from the container. Wave your hand over the opening of the container and “waft” the fumes towards your nose. • Never taste a chemical unless you are instructed by your teacher to do so. • Always clean up your work area and equipment after an experiment is completed. Equipment must be returned to its proper place. • Read and follow all directions exactly as they are written. If in doubt, ask your teacher for help! • Never mix chemicals (or perform tests) without your teacher’s permission.
Lab Safety Safety Rules: • Never mix chemicals without your teacher’s permission. • Never run (or push someone else) in the lab. ( this rule applies at all times!) • Keep lids on bottles and containers when not in use. • Never use broken or chipped glassware. • Keep your work area clean and keep all materials (clothing, hair, papers, etc.) away from a flame or heat source.
Lab Safety Safety Rules: • Always clean up your work area and equipment after an experiment is completed Equipment must be returned to its proper place. • Immediately notify your teacher if you get cut or have another injury when performing an experiment. • Wash your hands before and after each experiment.
Classwork • Complete the classwork in notebooks
Lesson • November 4, 2013
Earth’s Layers The Earth's rocky outer crust solidified billions of years ago, soon after the Earth formed. This crust is not a solid shell; it is broken up into huge, thick plates that drift atop the soft, underlying mantle.
The Crust • Outermost layer • 5 – 100 km thick • Made of Oxygen, Silicon, Aluminum
The Mantle • Layer of Earth between the crust and the core • Contains most of the Earth’s mass • Has more magnesium and less aluminum and silicon than the crust • Is denser than the crust
The Core • Below the mantle and to the center of the Earth • Believed to be mostly Iron, smaller amounts of Nickel, almost no Oxygen, Silicon, Aluminum, or Magnesium
Plate Tectonics • Greek – “tektonikos” of a builder • Pieces of the lithosphere that move around • Each plate has a name • Fit together like jigsaw puzzles • Float on top of mantle similar to ice cubes in a bowl of water
Continental Drift Alfred Wegener 1900’s Continents were once a single land mass that drifted apart. Fossils of the same plants and animals are found on different continents Called this supercontinent Pangea, Greek for “all Earth” 245 Million years ago Split again – Laurasia & Gondwana 180 million years ago http://members.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml
Sea Floor Spreading • Mid Ocean Ridges – underwater mountain chains that run through the Earth’s Basins • Magma rises to the surface and solidifies and new crust forms • Older Crust is pushed farther away from the ridge
How Plates Move http://pubs.usgs.gov/gip/dynamic/unanswered.html
Different Types of Boundaries http://pubs.usgs.gov/gip/dynamic/understanding.html
Divergent Boundary – Arabian and African Plates Arabian Plate Red Sea African Plate
Divergent Boundary – Iceland http://pubs.usgs.gov/gip/dynamic/understanding.html
Divergent Boundary - Oceanic http://www.geology.com
Divergent Boundary - Continental http://www.geology.com
Convergent Boundary – Indian and Eurasian Plates Eurasian Plate Indian Plate
Convergent Boundary – Oceanic & Continental http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com
Convergent Boundary – Oceanic & Oceanic Note – plates are reversed http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com
Convergent Boundaries - Continental http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com
Transform Boundary – San Andreas Fault www.geology.com
Review • Name the 3 main layers of the Earth • What is a tectonic plate? • What was Pangea? • What is Sea-Floor spreading? • Name the three different types of plate boundaries and one location on Earth for each one