theory of plate tectonics/what are tectonics plates?
The theory of plate tectonics explains the movements and interactions of tectonic plates on Earth's surface. Tectonic plates are large, rigid slabs of rocks that make up the Earth's outer layer, known as the lithosphere. These plates fit together like puzzle pieces and float on the semi-fluid layer underneath, called the asthenosphere.
There are three main types of tectonic plate boundaries:
1. Convergent Boundaries: This is where two plates collide. When two plates with continental crusts crash, they form mountains like the Himalayas. If an oceanic plate collides with a continental plate, the denser oceanic plate subducts or sinks beneath the continental plate, forming deep ocean trenches and volcanic arcs.
2. Divergent Boundaries: This is where two plates move apart. When plates separate, magma rises to fill the gap, creating new crust. This process occurs predominantly in the oceanic crust and forms mid-ocean ridges.
3. Transform Boundaries: This is where two plates slide horizontally past each other. This motion can cause earthquakes, as they build up stress due to the massive friction between the plates. The San Andreas Fault in California is an example of a transform boundary.
To understand the theory of plate tectonics, scientists use a combination of measurements, including GPS data, seismology (study of earthquakes), and the examination of rock formations and fossils. These geological observations combined with GPS monitoring have provided solid evidence for the theory of plate tectonics.