New 3D topography model helps to better understand the Earth’s mantle discontinuities and earthquakes
IU researchers Ian (Yinzhi) Wang and Gary Pavlis, Department of Geological Sciences, created a new 3D model of the topography of the Earth’s mantle discontinuities in the United States using Karst and enabled by the Science Applications and Performance Tuning (SciAPT) group. Earth, the planet that we live on, is extremely active both on the surface and in the interior. One of the most significant activities on its surface is understood as the plate tectonics, which is directly related to some disastrous geologic hazards such as volcano eruptions and earthquakes. Such surface activities intrinsically interact with the interior of the Earth. Therefore, a better understanding of the interior of the Earth is significant for explaining the nature of these disasters.
Bird’s eye view of the new model of the Earth’s mantle discontinuities for the United States.At the planetary scale, the interior of the Earth is divided into three layers: the crust, mantle, and core. The mantle lies between the core below and the crust above. It has an average thickness of 2,886 km and is characterized by a slow creeping motion of the solid mantle rocks caused by convection currents carrying heat from the interior of the Earth to the surface. The mantle is further divided into three sections: the upper mantle, the transition zone, and the lower mantle. The transition zone, which lies in the mid-mantle, is bounded by two discontinuities at depths around 410 and 660 km that are observed globally. This new model shows that the convective flow can significantly deflect these discontinuities from its normal depth. The observation of small-scale roughness of these discontinuities marks a completely new way to infer motion of the mantle at these depths. These findings have significant implications for the understanding of Earth’s dynamics that links to earthquakes and geologic hazards