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The supercontinent that formed 200 million years ago that included all of the land masses known to be on Earth at that time
the theory that states all continents are on large plates that moved and carried the continents to their current positions
Four reasons scientists think Pangaea existed
Rock formations are the same on different continents; Mountain formations are the same age; Fossil evidence of plants and animals; Glacier and fossil evidence
a theory that the Earth's crust is made up of many plates that move slightly as they gloat on the mantle, driven by the Earth's heat energy (convection currents)
Ocean trenches and volcanic islands are formed when
an oceanic and a continental plate come together.
Boundaries where plates split or come apart. The spreading allows magma from the mantle to form new crust.
Transform Fault Boundary
Boundaries where plates grind or slide past one another. Also known as a "strike-slip" boundary. Earthquakes can occur.
a jolting that occurs when two plates try to move past one another. These are caused by plate movement.
the weak point of fracture in the Earth's surface where the rock layers have ruptured and/or slipped. (This is where most earthquakes and volcanoes are located.)
a scale based on the numbers one to ten, that measures the energy released in an earthquake.
rocks made from magma. Usually made of mineral crystals of different sizes. Often has pores or holes in it.
rocks made from dirt, sand, and pieces of rock. Often formed in layers and often contain fossils.
The breakdown of rocks into smaller pieces without changing the type of material.
Example of physical weathering is
"frost wedging," caused by water that seeps into small cracks and freezes; the frozen water expands, forcing the crack to enlarge.
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