Plate tectonic theory is based on several assumptions about tectonic processes: 1) that new material is generated by sea-floor spreading at the mid-ocean ridges, which once formed become part of a plate, 2) that surface area is conserved, therefore plate material must be destroyed through another process, and 3) motion ...
What are the 4 things that plate tectonics theory explains?
Incorporating the much older idea of continental drift, as well as the concept of seafloor spreading, the theory of plate tectonics has provided an overarching framework in which to describe the past geography of continents and oceans, the processes controlling creation and destruction of landforms, and the evolution ...
What is the basic idea of the theory of plate tectonics quizlet?
What is the basic premise of the plate tectonic theory? Plate tectonic theory states that the Earth's crust is divided into several plates . These plates glide on the slowly moving rock on Earth's surface.
What are the 4 main lines of evidence for plate tectonics?
There is variety of evidence that supports the claims that plate tectonics accounts for (1) the distribution of fossils on different continents, (2) the occurrence of earthquakes , and (3) continental and ocean floor features including mountains, volcanoes, faults, and trenches.
What are the 3 theories of plate tectonics?
The three types of plate boundaries are divergent, convergent, and transform . They are described in the following three concepts. Most geological activity takes place at plate boundaries.
What are the 2 theories behind why tectonic plates move?
Why do plates move? One explanation for plate movements is slab pull . Plates are extremely heavy so gravity acts upon them, pulling them apart. Alternatively, as shown in the diagram, convection currents under the Earth's crust transfer heat, which rises through the surface and cools back down in a circular motion.
What are the theories of plate tectonics?
The theory of plate tectonics states that the Earth's solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere , the molten upper portion of the mantle. Oceanic and continental plates come together, spread apart, and interact at boundaries all over the planet.
What causes the plates to move?
The heat from radioactive processes within the planet's interior causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.
How many plate tectonics are there?
how many tectonic plates are there? There are major, minor and micro tectonic plates. There are seven major plates : African, Antarctic, Eurasian, Indo-Australian, North American, Pacific and South American.
How do plate tectonics affect humans?
Plate tectonics affects humans in several important ways. What would Earth be like without plate tectonics? We'd have many fewer earthquakes and much less volcanism, fewer mountains, and probably no deep-sea trenches. ... In other words, the Earth would be a much different place.
What is plate tectonics in your own words?
Plate tectonics is a theory which states that Earth's surface is made of plates that move with respect to one another. The word tectonic means “builder” and refers to the forces that shape Earth's crust.
What is a plate in the concept of plate tectonics quizlet?
tectonic plate. a piece of the lithosphere that moves around on top of the asthenosphere. lithosphere. the solid part of the earth consisting of the crust and outer mantle.
When two plates meet this is called?
Most volcanoes, mountains, and earthquakes occur where plates meet. Places where plates meet are called plate boundaries . There are seven major plates along with countless minor plates. You can see that a plate can be made of both oceanic crust and continental crust.
What are 5 pieces of evidence that support continental drift?
The evidence for continental drift included the fit of the continents; the distribution of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic zones .
What are the three main causes of plate movement?
Mantle dynamics, gravity, and Earth's rotation taken altogether causes the plate movements. However, convectional currents are the general thought for the motion.
What are the three main plate margins?
- Convergent boundaries: where two plates are colliding. Subduction zones occur when one or both of the tectonic plates are composed of oceanic crust. ...
- Divergent boundaries – where two plates are moving apart. ...
- Transform boundaries – where plates slide passed each other.
