In plate tectonics, what happens at a destructive margin?

Destructive margins occur when two tectonic plates are moving into each other, forcing one beneath the other. There are three types of destructive margin; Oceanic to Oceanic Plates, Continental to Continental plates, and Oceanic to Continental plates. 1.Oceanic tectonic plates are more dense than continental plates, and will sink beneath them when they collide. The oceanic plate then melts when it reaches the mantle, forming a convection current. While the oceanic plate melts, the continental plate crumples slightly under the pressure to create a fold mountains. The whole process pushes new magma up through the now made convection currents (Volcanoes.) The release of friction and pressure then causes Earthquakes, and Tsunamis by default. 2.When two oceanic plates meet, either Plate could crumple as they are the same density. After the subduction of one plate, a trench forms and they crumple to make an ocean ridge (Underwater fold mountains.) The Plate which was pushed into the mantle melts in the magma and pushes new magma up through the now made convection currents (Underwater Volcanoes.) This destructive margin may also cause earthquakes and tsunamis. (Example: The Pacific Ring of Fire)3.Lastly, when two continental plates meet at a destructive margin, neither Plate is able to sink below the other as they are the same density. The edges of the plates smash together to create a deep rooted fold mountain.These boundaries are where the Earth's crust is at its thickest (Example: The Himalayas)