IAG-IASPEI 2017

Presentation information

Oral

Joint Symposia » J02. Recent large and destructive earthquakes

[J02-4] Recent large earthquakes IV

Wed. Aug 2, 2017 4:30 PM - 6:00 PM Intl Conf Room (301) (Kobe International Conference Center 3F, Room 301)

Chairs: Shin-Chan Han (University of Newcastle) , Thorne Lay (University of California Santa Cruz)

5:30 PM - 5:45 PM

[J02-4-05] Linking Oceanic Tsunamis and Geodetic Gravity Changes of Large Earthquakes

Yuning Fu1, Y. Tony Song2, Richard Gross2 (1.Department of Geology, Bowling Green State University, Bowling Green, Ohio, USA, 2.NASA Jet Propulsion Laboratory)

Large earthquakes at subduction zones usually generate tsunamis and coseismic gravity changes. These two independent oceanic and geodetic signatures of earthquakes can be observed individually by modern geophysical observational networks. The Gravity Recovery and Climate Experiment (GRACE) twin-satellites can detect gravity changes induced by large earthquakes, while altimetry satellites and Deep-Ocean Assessment and Reporting of Tsunamis (DART) buoys can observe resultant tsunamis. In this study, we introduce a method to connect the oceanic tsunami measurements with the geodetic gravity observations, and apply it to the 2004 Sumatra Mw 9.2 earthquake, the 2010 Maule Mw 8.8 earthquake and the 2011 Tohoku Mw 9.0 Earthquake. Our results indicate consistent agreement between these two independent measurements. Since seafloor displacement is still the largest puzzle in assessing tsunami hazards and its formation mechanism, our study demonstrates a new approach to utilizing these two kinds of measurements for better understanding of large earthquakes and tsunami