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The Theory of Plate Tectonics - Coggle Diagram
The Theory of Plate Tectonics
The Plate Tectonics Theory
The theory of plate tectonics which was proposed in the late 1960's states that Earth's surface is made of rigid slabs of rock, or plates, that move with respect to each other.
This theory suggests that Earth's surface is divided into large plates of rigid rock.
Geologists use the word tectonic to describe the forces that shape Earth's surface and the rock structures that form as a result.
The asthenosphere enables Earth's plate to move because the hotter, plastic mantle material beneath them can flow.
The pacific plate is the largest plate, and the Juan de Fuca is one of the smallest.
Key Concepts/Essential Questions
Why do tectonic plates move?
The heat from radioactive processes within the planet's interior causes the plates to move.
What are the three types of plate boundaries?
The three types of plate boundaries are Transform Plate boundaries, Divergent Plate boundaries, and Convergent Plate boundaries.
What is the theory of plate tectonics?
The theory of plate tectonics states that Earth's surface is made of rigid slabs of rock, or plates, that move with respect to each other. This theory suggested that Earth's surface is divided into large plates of rigid rocks.
Evidence for Plate Tectonics
By keeping track of the distance between these satellites and Earth, it is possible to locate and determine how fast a tectonic plate moves.
This theory also provides a valid explanation for why earthquakes and volcanoes in certain places.
A network of satellites called the Global Positioning System (GPS) orbiting Earth, monitors plate motion.
When plates separate, collide, or slide past each other rapidly along a plate boundary it can result in earthquakes.
Beforehand, there wasn't very high technology that could be used to measure how fast continents move.
Lastly, volcanoes form where plates separate along a mid-ocean ridge or a continental rift or collide along a subduction zone.
To begin with, the main evidence on why do people and scientists believe inThe Plate Tectonics Theory is because continents move apart or come together at speeds of a few centimeters per year (length of a small paperclip).
Mountains can form where two continents collide.
Plate Motion
Forces causing Plate Motion
Basal Drag:
Convection currents in the mantle produce a force that causes motion called basal drag. Convection currents in the asthenosphere circulate and drag the lithosphere.
Nevertheless, scientists are still uncertain about which force has the greatest influence on plate motion.
Ridge Push:
Rising mantle material at mid-ocean ridges creates the potential for plates to move away from the ridge with a force called ridge push. Remember that ridge push moves lithosphere in opposite directions away from the mid-ocean ridge.
Slab Pull:
When tectonic plates collide, the denser plate will sink into the mantle along a subduction zone. This plate is called a slab. As a slab sinks, it pulls on the rest of the plate with a force called slab pull.
Plate tectonic activity is related to convection in the mantle, as the the lithospheric plates move over the asthenosphere.
A Theory in Progress
Plate tectonics has become the unifying theory of geology. This is because it explains the connection between continetal drift, the occurrence of earthquakes, volcanoes, mountains, and the formation and destruction of crust along plate boundaries. However the theory of Wegener is still being revised, and several unanswered questions remain.
Unanswered questions:
Why is Earth the only planet in the solar system that has plate tectonic activity?
Why do some earthquakes and volcanoes occur far away from plate boundaries?
What forces dominates plate motion?
What will scientists investigate next?
Vocabulary
Divergent plate boundary
Forms where two plates separate.
Convergent Plate Boundary
A convergent plate boundary is a form where two plates collide.
Lithosphere
Lithosphere is the cold and rigid outermost rock layer.
Transform Plate Boundary
Forms where two plates slide past eachother.
Plate Tectonics
Plate Tectonics is a theory that states or claims that Earth's surface is made of rigid slabs of plates that move with respect to each other.
Subduction
From what I've learned, I know that subduction is the process in which the denser plate sinks below the more buoyant plate.
Convection
A convection is the circulation of material caused by differences in temperature and density.
Ridge push
Ridge push: A force which results when magma rises at a mid-ocean ridge and pushes oceanic plates in two different directions away from the ridge.
Slab Pull
Slab pull: A force that causes a dense oceanic plate to sink beneath a more buoyant plate along a subduction zone, pulling the rest of the plate that trails behind it.
Plate Boundaries
Divergent Plate Boundaries
They form two separate plates and they are most common in mid-ocean ridges. In fact, when the sea floor spreads at a mid-ocean ridge , lava erupts, cools, and forms new oceanic crust.
Convergent Plate Boundaries
They form where two plates collide.The denser the plate sinks below the more buoyant plate in a process called subduction. When an oceanic plate and a continental plate collide, the denser the oceanic plate sub-ducts under the edge of the continent. When two continental plates collide, neither plate is sub ducted, and mountains such as Himalayas in souther Asia form from uplifted rock.
Transform Plate Boundaries:
They form where two plates slide past each other, and a fault system is produced. This system can result in a rapid release of energy as earthquakes.