The Boundary That Separates the Crust from the Mantle Is

Q14: The study of ancient magnetic fields is

Q15: The presence of an S-wave shadow zone

Q16: The _ is the transition zone at

Q17: High _ is usually an indication of

Q18: The rock record for tens of millions

Q20: Detailed images provided by _ suggest that

Q21: The greatest negative gravity anomalies in the

Q22: At a pressure equivalent to a depth

Q23: Heat flow _ the crest of the

Q24: Most of the evidence for magnetic reversals