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Insight to the enigmatic origin of the Hangai Dome in central Mongolia

Screen shot 2015-08-28 at 4.04.14 PMThe Hangai Dome in central Mongolia is one of the most bizarre high-elevation places in continental interiors on Earth. The Indian plate collides with the Eurasian plate to its southwest and the Pacific plate subducts under the Eurasian plate to its east. However, the Hangai Dome is very far (thousands of kilometers) away from the plate margin of East Asia where the tectonic plates converge. There have been debates on mechanisms that caused the uplift of Hangai Dome, whether it’s driven by the movement of tectonic plates or caused by the hot mantle rock rising from the deeper interior of the Earth. The new study by Chen et al. (2015, GRL) shows a clearly imaged localized deep mantle upwelling that generated magma in the rigid shell of the Earth (movie). The heat released by the magma makes the lithosphere underlying the dome more buoyant that caused the surface uplift of the dome. This unique example of continental uplift shows that the active mantle also plays an important role in shaping the Earth’s landscape and consequently the ecological habitat. For more detailed information on seismic adjoint tomography technique and data used in constructing the 3-D seismic model, please check out a different article by Chen et al. (2015, JGR) published earlier this year.