On Sept. 29, 2009, an 8.1-magnitude earthquake struck near American Samoa, Samoa, and Tonga, triggering a tsunami that caused human casualties and $200 million in property damage on the islands. The earthquake also exacerbated another problem in American Samoa: subsidence, or the sinking of land. When combined with relative sea level rise, land sinking can increase the frequency and amount of coastal flooding.
Click here for original story, NASA researchers measure sinking land in American Samoa
Source: Phys.org