Tectonic Plate Theory & Boundaries
Austin Williams
Background
Alfred Wegener proposed the continental drift theory in 1915 that 100 million years ago, the continents were put together as a super continent called Pangaea. Over time evidence was found to prove his theory. Like finding similar fossils in different continents and the continents looked like they could fit together like a jig saw puzzle. There were three main boundaries that caused the continental drift. Convergent, Divergent, Transform
CONVERGENT BOUNDARIES
Convergent boundaries occur when two or more plates collide with each other.
What do Convergent Boundaries Form?
Convergent boundaries form mountains, trenches , volcanoes. An example of a convergent boundary is Mt. Everest- Himalayas.
Subduction
Subduction is when one plates slides beneath another. This can only form at convergent boundaries. Subduction can make volcanic mountains and ocean trenches. An example of subduction is Marianas Trench in the Pacific Ocean.
DIVERGENT BOUNDARIES
Divergent Boundaries occur when two plates pull away from each other
What do Divergent Boundaries form?
Divergent boundaries form rift valleys on land and seafloor spreading underwater. An example is Iceland, Africa or the Mid Atlantic Ridge.
Transform Boundaries
Transform boundaries occur when two plates slide past each other.
What do Transform Boundaries form?
Transform boundaries can create faults and earthquakes. An example of a transform boundary is the San Andreas Fault in California.