ThesuggesteddiscussionisbasedontheconclusionsdrawnupinconncctionwiththedevelopmentofmodelsofmctallogeniccontrastordiffcrentblocksofthecarthcrustoftbeCaucasusandotherre-gions.PropositionswereputforwardaccordingtowhichmotallogeniccontrastoftheEarthisthecon-sequenceof:-contrastofsynchronousgcodynamicre