It can be tissues or chemical level
The metals are found at the left side of the periodic table, the non metals are found at the middle part of the periodic table and the noble gases are found at the right side.
The age of continental rocks are far more older compared to the age of oceanic rock since oceanic rock are destroyed in the mantle as they undergo subduction process whereas continental rocks will not be destroyed.
Continental rocks will not undergo a process known as subduction in the convergent boundary since continental plate have a lesser density compared to oceanic plate. On the other hand, oceanic plate (rocks) will undergo subduction process in the convergent boundary since they have more density and they will be destroyed as they are plunges towards the mantle.
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