New evidence about the existence of a transition zone between the lower mantle and the core is presented. In 1964 the Author proved this zone is about 160 Kms thick and velocity of elastic waves decreases in it gradually. Now he judges the velocity of P wave, at the bottom of the transition zone, of 10 Kms/sec order. The zone appears layered, as the record of intervalled, successive pulses proves. For the justification of this zone the theory of Ramsey is thought appropriate.
Referenze Bibliografiche
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Con il contributo del Ministero per i Beni e le Attività Culturali