Week 6: pangea was the last super continent, the tethys ocean was a region of pangea. Big deal about this ocean is that it has closed: the french alps, zagros mountains, the high himalayas---- are all part of an alpine- Ocean: orogeny is the process of mountain building, oregon is the name we give to folding thrust belt, may include ophiolites. It is a deformed rock that result from orogeny: pacific ring of fire: big earthquakes and major volcanoes are mostly here. This is an ocean that"s dying in the present day. Because all the surrounding continents are all encroaching on the pacific ocean crust. Answer: subduction: pacific ocean is a dying ocean, expressed as the ring of fire", pacific ring of fire- think about it as a factory, where we are converting ocean floor crust converted into continental crust.