Evidence from fossils, glaciers, and complementary coastlines helps reveal how the plates once fit together. Fossils tell us when and where plants and animals once existed. Some life “rode” on diverging plates, became isolated, and evolved into new species.
What are the 4 pieces 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.
Which of the following is an evidence of the plate tectonics theory quizlet?
Earthquakes and volcanic activity are also evidence of plate tectonics.
Which of the following was early evidence for plate tectonics?
Rock unearthed from a mountain belt in northeastern South Africa has shown the earliest known evidence of plate tectonics, pre-dating their previous known existence by 240 million years, according to researchers.
What drives plate tectonics?
What drives the movement of tectonic plates? Below the tectonic plates lies the Earth’s asthenosphere. ... Three of the forces that have been proposed as the main drivers of tectonic plate movement are: mantle convection currents : warm mantle currents drive and carry plates of lithosphere along a like a conveyor belt.
What causes plate tectonics?
Plate motions cause mountains to rise where plates push together, or converge, and continents to fracture and oceans to form where plates pull apart, or diverge . The continents are embedded in the plates and drift passively with them, which over millions of years results in significant changes in Earth’s geography.
What is the mechanism of plate tectonics?
As the lithosphere formed at divergent plate margins is hot, and less dense than the surrounding area it rises to form oceanic ridges. The newly-formed plates slide sideways off these high areas, pushing the plate in front of them resulting in a ridge-push mechanism .
What are the three types of lithospheric plate boundaries?
The movement of the plates creates three types of tectonic boundaries: convergent, where plates move into one another; divergent, where plates move apart; and transform, where plates move sideways in relation to each other . They move at a rate of one to two inches (three to five centimeters) per year.
How fast do tectonic plates move?
They can move at rates of up to four inches (10 centimeters) per year , but most move much slower than that. Different parts of a plate move at different speeds. The plates move in different directions, colliding, moving away from, and sliding past one another. Most plates are made of both oceanic and continental crust.
How many tectonic plates 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 are glaciers evidence of plate tectonics?
The findings suggest that sediment lubrication controls the rate at which Earth’s crust grinds and churns. Sobolev and Brown found that two major periods of worldwide glaciation, which resulted in massive deposits of glacier-scrubbed sediment, each likely caused a subsequent boost in the global rate of plate tectonics.
What are the 5 evidences of continental drift theory?
They based their idea of continental drift on several lines of evidence: fit of the continents, paleoclimate indicators, truncated geologic features, and fossils .
What are the 3 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 two main factors of tectonic plates movement?
Heat and gravity are fundamental to the process
The energy source for plate tectonics is Earth’s internal heat while the forces moving the plates are the “ridge push” and “slab pull” gravity forces. It was once thought that mantle convection could drive plate motions.
What are the two types of crust?
Earth’s crust is divided into two types: oceanic crust and continental crust . The transition zone between these two types of crust is sometimes called the Conrad discontinuity. Silicates (mostly compounds made of silicon and oxygen) are the most abundant rocks and minerals in both oceanic and continental crust.
What are the types of plate tectonics?
There are three kinds of plate tectonic boundaries: divergent, convergent, and transform plate boundaries . This image shows the three main types of plate boundaries: divergent, convergent, and transform. Image courtesy of the U.S. Geological Survey. Download image (jpg, 76 KB).
