A scientist named Alfred Wegener came up with the theory of continental drift. The theory was that the continents broke apart from a supper continent called Pangea.
Transform boundaries occur when two plates slide past each other horizontally. The stress or tension at this boundary is called shearing, also called a Strike - Slip fault.
Convergent boundaries consist of oceanic and continental crust. When the two plates collide and the one with the bigger density stays as the other plate slide under the other. Subduction occurs when the oceanic crust goes under the continental crust. This can create volcanoes.
Divergent boundaries occur when two plates move away from one another an example is Mid - Atlantis ridge. As the sea floor spreads, magma flows through the crack because of the convection current that allows the magma to move.
Earthquakes are recorded and put into details by seismographs. The Richter scale measures the magnitude of an earthquake. The epicenter of an earthquake is the point on the earth's surface directly above the focus of an earthquake. Triangulation is commonly used by geologists to find earthquakes. Triangulation is a way of finding somethings location using the location of other things. Earthquakes have two major waves, P waves always travel ahead of S waves but don't have as much impact, S waves are slower than P waves but have more of an impact.
Two types of volcanic eruptions, explosive and nonexplosive. In explosive eruptions, clouds of hot gas shoot out of the volcano and instead of lava, there are a ton of molten rock pieces that harden. In nonexplosive eruptions, lava flows are relatively calm and do not explode out of the volcano. Cinder is a small piece of partly burned coal that has stopped giving off flames but still is combustible. A shield volcano is a broad, domed volcano with gently sloping sides. A composite volcano is a volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. The volcanoes in the pacific Ring of Fire are the most active volcanoes in the world. The volcanoes are formed due to subduction zones of three main active tectonic plates namely the Eurasian Plate, Pacific Plate, and Inde Australian Plate.