Waltemath described one of the proposed moons as being 1,030,000 km (640,000 mi) from Earth, with a diameter of 700 km (430 mi), a 119-day orbital period, and a 177-day synodic period.
A subduction zone is formed at a convergent plate boundary when one or both of the tectonic plates is composed of oceanic crust. The denser plate, made of oceanic crust, is subducted underneath the less dense plate, which can be either continental or oceanic crust.s a result of pressure, friction, and plate material melting in the mantle, earthquakes and volcanoes are common near convergent boundaries. When two plates move towards one another, they form either a subduction zone or a continental collision. This depends on the nature of the plates involved.
Subduction zones. Subduction zones form when an oceanic plate collides with another oceanic plate or continental plate. The continental crust is lighter and less dense than oceanic crust. Continental crust's density is approximately 2.7 grams per cubic centimeter.Oceanic crust is thinner and the average density is about 3.3 cubic centimeters.When the two crustal plates converge the oceanic plate always bends and subducts beneath a continental plate. convergent boundary forms when two continental plates collide. Neither plate subducts because the crusts have approximately the same density. Instead, the rocks are smashed together causing them to recrystallize due to the intense heat and pressure from the colliding plates.