According to Alfred Wegener, all the major continents formed one giant supercontinent, called Pangaea. About 200 million years ago, the supercontinent Pangaea began to rift.
Oceanic trenches are long and narrow depressions of the sea floor. They are the deepest parts of the ocean floor. They are a type of tectonic landforms.Horst is a raised fault block bounded by normal faults. The word Horst in Dutch and German means ‘heap’. It is a raised block of earth’s crust that has been lifted. It is a tectonic landform.