Did you know that Pangea, the supercontinent, is now our seven split up continents? It was the landmass when all the continents were joined, but split up in the Mesozoic Era. You see, if you take the continents, and put them together, they'd fit pretty well. Identical plant and animal fossils have been found in different continents with a complete different climate. Perhaps these animals and plants could only survive in a certain type of climate. That suggests the continents were once connected.
-Plate Tectonics-
The theory of Plate Tectonics states that Earth's outermost layer, the lithosphere, is broken into eight large pieces that float on the asthenosphere, the upper mantle. The eight large pieces of the lithosphere are the African, Antartic, Eurasian, Indian-Australian, Nazca, North American, Pacific and South American. Some of the smaller pieces are the Anatoliah, Arabian, Caribbean, Cocos, Philippines, Somali, and Juan de Fuca. These plates are being pushed by convection currents and move 1cm. per year!
-Boundaries-
The place were the plates meet are the boundaries. When the plates are colliding, it's called Convergent Boundaries. When the plates are pulling apart, it's called Divergent Boundaries. When the plates are sliding past each other, it's called Transform Boundaries. Earthquakes are formed by Transform boundaries. Volcanoes are formed by Convergent boundaries. Divergent boundaries move the plates apart and new land forms.
-The Ring of Fire-
The Ring of Fire streches from New Zealand, along east Asia, across the north of Alaska, and south along the coast of North and South America. The Ring of Fire is composed over 75% of the world's active volcanoes. Around the Ring of Fire, the Pacific plate is colliding and sliding beneath other plates, or subducting. The energy formed can melt the rock into magma which rises to the surface and forms volcanoes.
-Mid-Ocean Ridge-
Mid-Ocean Ridges are underwater mountain chains that extend through the Atlantic, Indian, and South Pacific Ocean. Mid-Ocean ridges have valleys, or rifts, that run along with them. These underwater mountains and valleys mark where the Earth's crust move. This oceanic ridge is known as oceanic spreading center, which is responsible for seafloor spreading. Mid-Ocean ridges are places where the Earth's tectonic plates move apart. As they do, magma rises and filled up the gaps, form land, and may cause volcanic eruptions. The magma provides a heat source that creates seafloor hotsprings along the ridges which transfer heat and chemicals into the ocean.
