Detection of small scale heterogeneities at the Inner Core Boundary

We also deduce from the amplitude ratios that the attenuation is stronger than the global average at the top of the inner core in this region, as expected from its location in the eastern hemisphere. Our results confirm the presence of a low attenuation zone at the top of the inner core, followed by a highly attenuating layer centered around 35 km depth in the inner core, as found in the eastern hemisphere in previous studies. This zone is however thinner (15 km) and more attenuating, Qα reaching values less than 50.