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This paper introduces relative and absolute gravity change observations in the eastern portion of the Tibetan Plateau. We analyze and discuss a change that occurred in 2010 in the gravity along the eastern margin of the plateau and the relationship between this change and the 2013 Lushan MS7.0 earthquake. Our results show that: (1) before the Lushan MS7.0 earthquake, gravity anomalies along the eastern margin of the Tibetan Plateau changed drastically. The Lushan earthquake occurred at the bend of the high gradient zone of gravity variation along the southern edge of the Longmenshan fault zone. (2) The 2013 Lushan earthquake occurred less than 100 km away from the epicenter of the 2008 Wenchuan earthquake. Lushan and Wenchuan are located at the center of a four-quadrant section with different gravity anomalies, which may suggest that restoration after the Wenchuan earthquake may have played a role in causing the Lushan earthquake. (3) A medium-term prediction based on changes in gravity anomalies was made before the Lushan MS7.0 earthquake, in particular, a prediction of epicenter location.

Recently, in comparing with Earth rotation data, we found some exciting correlation phenomena between length-of-day (LOD) and crustal deformations as well as stress observations in China, the correlation appears most typically on decade time scales and seems to be direction-dependent. As LOD variation induced stress and deformation is far less than the observed ones, we infer that decade variations in crustal deformation and stress are very possibly attributed to the core-mantle coupling process, just like LOD decade variations are attributed to core-mantle coupling. More detailed and extended investigations are going on, and we believe that the similar correlation phenomena should also exist in other part of the world. The LOD-correlated crustal deformations are expected to provide a better constraint on verifying the real core-mantle coupling mechanism, topographic, electromagnetic or gravitational coupling.