PROBING THE DEEP EARTH
SEISMOLOGY
USES THE TRAVEL TIMES AND AMPLITUDES OF SEISMIC WAVES TO STUDY VARIATIONS IN SEISMIC WAVE VELOCITY AND DENSITYGRAVITY
STUDIES MEASURE VARIATIONS IN DENSITYMAGNETIC
STUDIES GIVE INSIGHT INTO THE CORE'S MAGNETIC FIELDTOGETHER WITH RESULTS FROM LABORATORY STUDIES OF ROCK PROPERTIES AND OTHER DATA THESE YIELD OUR MODELS OF THE EARTH'S COMPOSITION, TEMPERATURE, AND INTERNAL PROCESSES