Mesosaurus: Warm Up: describe what you think this map represents

The Formation of Earth Video You need to write everything in GREEN Describe the early evolution of the Earth and solar system, including the formation of Earth’s solid layers, the distribution of major elements, the origin of internal heat sources, and the mechanism by which heat transfer drives plate tectonics.

Origin of the Universe The Big Bang Model 14 billion years ago All matter existed in a hot and dense state Space itself was expanding As it expanded and cooled, it began to form stars and galaxies. The first stars consisted of Hydrogen and a small amount of Helium

And then there was Earth More and more stars formed As the stars grew older they began to die This caused more and more matter to be able to fuse into heavier elements. These elements were expelled back into interstellar space. Eventually this cloud of GAS and DUST lead to the formation of our Solar System (the Sun and its nine planets) This occurred 4.5 Billion years ago

Composition of Earth Crust: thin rigid layer of rocks Mantle: Composed of compounds rich in iron, silicon, and magnesium. (67% of Earth’s mass) Outer Core: Liquid iron and nickel Inner Core: Solid iron and nickel

Composition of the Earth

The Crust This is the layer we live on It contains two major rock categories: Oceanic Crust is Basalt Continental Crust is Granite The majority of the elemental composition of the crust is oxygen and silicon. The differences in densities of these rock types account for the oceans and continents on Earth

The Crust The continental crust is LESS dense than the oceanic, therefore it rises above sea level. The amount of Oceanic crust is partially responsible for 70% of Earth being covered by water. Of that 70% only 3% is freshwater!

**Note Check** What is the inner most layer of Earth? How long ago did the universe form? What did the universe form from? Is oceanic crust more or less dense than continental crust?

The Mantle The THICKEST layer Contains Iron, Magnesium, and Silicon Where Convection takes place

Mantle Convection The driving force for Plate Tectonics Evidence of Continental Drift

Continental Drift Continental drift was a theory that explained how continents shift position on Earth's surface. Set forth in 1912 by Alfred Wegener, a geophysicist and meteorologist Continental drift also explained Glacial scaring left on multiple continents that are now warm climates why look-alike animal and plant fossils, and similar rock formations, are found on different continents Example Mesosaurus

Glacial Deposits and Scars

Mesosaurus

The Core Outer Core Inner Core Liquid iron and nickel Solid iron and nickel