What are tectonic plates easy definition?
A tectonic plate (also called lithospheric plate ) is a massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. Continental crust is composed of granitic rocks which are made up of relatively lightweight minerals such as quartz and feldspar.
Where are the tectonic plates?
The outermost part of Earth’s structure is known as the lithosphere. The lithosphere consists of the crust and small portion of the upper mantle. The lithosphere is divided into a number of tectonic plates. These plates move and interact with one another, driven by convectional forces within the Earth.
What are tectonic plates 7?
Explanation: Pieces of the Earth’s crust and the uppermost mantle that together form the lithosphere are known as tectonic plates or lithospheric plates. Mediterranean Plate is not a tectonic plate.
What are the 4 types of tectonic plate movement?
Tectonic Plates and Plate Boundaries 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.
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. The Hawaiian Islands were created by the Pacific Plate, which is the world’s largest plate at 39,768,522 square miles.
Why do we have tectonic plates?
Without plate tectonics our planet would be a very different place. The constant recycling of the Earth’s crust provides us with a stable climate, mineral and oil deposits and oceans with a life-sustaining balance of chemicals.
How fast do tectonic plates move?
They move at a rate of one to two inches (three to five centimeters) per year.
How tectonic plates are formed?
Earth’s tectonic plates may have taken as long as 1 billion years to form, researchers report today in Nature1. The plates — interlocking slabs of crust that float on Earth’s viscous upper mantle — were created by a process similar to the subduction seen today when one plate dives below another, the report says.
What are the 12 major plates?
Primary plates African plate. Antarctic plate. Indo-Australian plate. North American plate. Pacific plate. South American plate. Eurasian plate.
What are the 3 theories of plate tectonics?
Three-dimensional diagram showing crustal generation and destruction according to the theory of plate tectonics; included are the three kinds of plate boundaries —divergent, convergent (or collision), and strike-slip (or transform).
Why do tectonic plates move Class 7?
These plates are move slowly (just a few millimetres every year). This is because of the heat generated by the molten magma of the earth inside it. The molten magma inside the earth moves in a circular manner. The movement of these plates causes changes on the earth surface.
What are tectonic plates Class 6?
WHAT ARE TECTONIC PLATES? The outermost layer of the earth is called the crust and it is broken into large pieces called tectonic plates. These huge pieces of Earth’s surface slowly move at about the speed that your fingernails grow.
What are the 2 tectonic plates called?
There are two main types of tectonic plates: oceanic and continental. Oceanic – Oceanic plates consist of an oceanic crust called “sima”.
What happens when tectonic plates hit each other?
When oceanic or continental plates slide past each other in opposite directions, or move in the same direction but at different speeds, a transform fault boundary is formed. No new crust is created or subducted, and no volcanoes form, but earthquakes occur along the fault.