The region where plates meet is called the plate boundary. The movement of plates regulates what happens at plate boundaries. The plates move apart, collide, or slide past each other, and are found at mid-ocean ridges.

New crust forms at the spreading boundaries. For instance, Iceland, an island in the north Atlantic, developed at the spreading boundary along the Mid-Atlantic Ridge.                     Volcanoes condense and the earth shakes with great regularity along the mid-ocean ridge and at other spreading boundaries. When Pangaea broke, it separated along the Mid-Atlantic Ridge and took 200 million years for the Atlantic to grow to its’ present size.                                                                                 Spreading boundaries are also called divergent boundaries, and form where two plates bump into each other.                                                                                                                The edge of one plate sinks into the mantle under the edge of another plate.                    That’s where the mantle absorbs the edge of the sinking plate,  and heat and pressure create volcanoes and earthquakes.

                                                                                                  Pressure along colliding plates may fold rock layers into huge mountain systems, for instance, the Himalayas in India.                                                                                                    Colliding boundaries are also called convergent, consuming or subducting boundaries. Ditches, also known as trenches border the Pacific Ocean, where the Pacific plate is sinking. The size of the plate decreases as it sinks into the trenches.                                                                The Pacific Ocean is shrinking slowly, and the loss of crust in the trenches stabilities the formation of new crust in the mid-ocean ridges.People who live near the fault, the fault being cracks in the earth, must expect earthquakes.

Sliding boundaries are also called translational or transform boundaries.The theories and evidence provided above, assist evaluating the theory of the earth’s structure movement and the changes.                                                                                             So, to value, Alfred Wegener proposed that the continents were once joined in a large continent called Pangaea, as wells as,• Wegener used rock layers, fossils, and changes of climate as evidence for continental drift.  • The mid-ocean ridge is a mountain chain 65,000km long in the oceans of the world.      • Magma rises from the mantle creating new ocean crust at the mid-ocean ridges. • The plate tectonic theory states that the rigid outer part of the earth is broken into a number of pieces called plates.

, the plates move apart, collide, or slide past one another.  • The flow of material in the mantle by convection and/or plumes (upwelling of abnormally hot rock within the earth’s mantle) may cause plate movement. • Hot spots are regions on the surface of the earth that lie directly over a p