Sang Mook Lee

Growing Understanding of Subduction Dynamics Indicates Need to Rethink Seismic Hazards

Tsunamigenic megathrust earthquakes, like the 2004 Sumatra-Andaman and 2011 Tohoku events, are the most dramatic consequences of subduction dynamics. The classical view is that megathrusts release elastic energy due to the rupture of a fault with a width of tens of kilometers in the down-dip direction and a length of hundreds to a thousand kilometers along the trench. However, recent research, particularly work on the Tohoku event, has suggested that the generation of huge tsunamis may require the release of gravitational energy as well as elastic energy [George et al., 2011]. Our growing understanding of the role of gravitational energy in generating tsunamis following megathrust earthquakes points to the need to reevaluate earthquake and tsunami hazard assessments.

Subduction dynamics: From mantle flow to mega disasters

Contributors vii Introduction: The Impact of Subduction Dynamics on Mantle Flow, Continental Tectonics, and Seismic Hazard Gabriele Morra, David A. Yuen, Scott D. King, Sang-Mook Lee, and Seth Stein 1 1 Evidence from Caustic Waveform Modeling for Long Slab Thickening above the 660 -km Discontinuity under Northeast Asia: Dynamic Implications Juan Li, Nicola Tosi, Petra Maierova, and David A. Yuen 5 2 The Continental Collision Process Deduced from the Metamorphic Pattern in the Dabie Hongseong and Himalayan Collision Belts Chang Whan Oh 19 3 A New Tectonic Model for the Genesis of Adakitic Arc Magmatism in Cretaceous East Asia Changyeol Lee and In -Chang Ryu 69 4 Incoming Plate Variations along the Northern Manila Trench: Implications for Seafloor Morphology and Seismicity Chuanxu Chen, Shiguo Wu, Jin Qian, Changlei Zhao, and Lingmin Cao 81 5 Source of the Cenozoic Volcanism in Central Asia Gabriele Morra, David A. Yuen, Sang -Mook Lee, and Siqi Zhang 97 6 Influence of Variable Thermal Expansivity and Conductivity on Deep Subduction Nicola Tosi, Petra Maierova, and David A. Yuen 115 7 Slab ]driven Mantle Weakening and Rapid Mantle Flow M. A. Jadamec 135 8 Influence on Earthquake Distributions in Slabs from Bimaterial Shear Heating Byung -Dal So and David A. Yuen 157 9 The Seismology of the Planet Mongo: The 2015 Ionospheric Seismology Review Giovanni Occhipinti 169 10 Why We Need a New Paradigm of Earthquake Occurrence Robert J. Geller, Francesco Mulargia, and Philip B. Stark 183 Index 193

Subduction: From mantle flow to great earthquakes

International Conference on Geophysics of Slab Dynamics;Jeju Island, South Korea, 19–22 August 2012 In a recent meeting on Jeju Island, South Korea, a community of researchers, half from East Asia and half from North America and Europe, came together to study subduction from complementary points of view—seismology, geodynamics, mineral physics, and tectonics—to enhance the synergy between subduction-related disciplines. The discussion focused on the predictability of the largest earthquakes, the origin of the interplate volcanism in Asia, the challenges for numerical modelers, and how the subduction process influences the evolution of the mantle.