Subduction zones are major convergent boundaries,where the downgoing oceanic plates usually form continuous tabular slabs extending deep into the Earth’s interior.However,many subducting slabs especially those with y...Subduction zones are major convergent boundaries,where the downgoing oceanic plates usually form continuous tabular slabs extending deep into the Earth’s interior.However,many subducting slabs especially those with young ages,exhibit complex geometry,with varying degrees of influence on the overlying continent and surface environment.To better understand the mechanism of such slab deformation,we apply four-dimensional finite element geodynamic models with data assimilation to investigate the evolution of the Cocos subduction in Central America,where a double-slab configuration with complex tearing has recently been observed.We reproduce the subduction history of the Cocos slab since the Eocene.During this period,multiple episodes of tearing occurred within the Cocos slab,starting at 25 Ma.We find that the ancient Farallon slab,subducted during the Mesozoic,enhances the lateral pressure gradient across the slab hinge,promoting eastward mantle flow and tearing of the Cocos slab.The repeated tearing and subduction of the young Cocos plate have shaped the complex slab configuration in the region.展开更多
The thermal evolution of the Earth’s interior and its dynamic effects are the focus of Earth sciences.However,the commonly adopted grid-based temperature solver is usually prone to numerical oscillations,especially i...The thermal evolution of the Earth’s interior and its dynamic effects are the focus of Earth sciences.However,the commonly adopted grid-based temperature solver is usually prone to numerical oscillations,especially in the presence of sharp thermal gradients,such as when modeling subducting slabs and rising plumes.This phenomenon prohibits the correct representation of thermal evolution and may cause incorrect implications of geodynamic processes.After examining several approaches for removing these numerical oscillations,we show that the Lagrangian method provides an ideal way to solve this problem.In this study,we propose a particle-in-cell method as a strategy for improving the solution to the energy equation and demonstrate its effectiveness in both one-dimensional and three-dimensional thermal problems,as well as in a global spherical simulation with data assimilation.We have implemented this method in the open-source finite-element code CitcomS,which features a spherical coordinate system,distributed memory parallel computing,and data assimilation algorithms.展开更多
1.Introduction The lithosphere is a fundamental component of Earth’s layered structure,and its stress state and deformation mechanisms are critical to understanding Earth’s tectonic evolution(Ghosh and Holt,2012)and...1.Introduction The lithosphere is a fundamental component of Earth’s layered structure,and its stress state and deformation mechanisms are critical to understanding Earth’s tectonic evolution(Ghosh and Holt,2012)and managing natural resources(Heidbach et al.,2018).According to the classical theory of plate tectonics,significant lithospheric deformation is expected near active plate boundaries due to the relative motion between tectonic plates.展开更多
The Hawaiian-Emperor seamount chain has shown two subparallel geographical and geochemical volcanic trends,Loa and Kea,since-5 Ma,for which numerous models have been proposed that usually involve a single mantle plume...The Hawaiian-Emperor seamount chain has shown two subparallel geographical and geochemical volcanic trends,Loa and Kea,since-5 Ma,for which numerous models have been proposed that usually involve a single mantle plume sampling different compositional sources of the deep or shallow mantle.However,both the dramatically increased eruption rate of the Hawaiian hotspot since-5 Ma and the nearly simultaneous southward bending of the Hawaiian chain remain unexplained.展开更多
基金supported by the Strategy Priority Research Program(Category B)of the Chinese Academy of Sciences(Grant No.XDB0710000)the National Natural Science Foundation of China(Grant No.92355302)supported by the National Supercomputer Center in Tianjin.
文摘Subduction zones are major convergent boundaries,where the downgoing oceanic plates usually form continuous tabular slabs extending deep into the Earth’s interior.However,many subducting slabs especially those with young ages,exhibit complex geometry,with varying degrees of influence on the overlying continent and surface environment.To better understand the mechanism of such slab deformation,we apply four-dimensional finite element geodynamic models with data assimilation to investigate the evolution of the Cocos subduction in Central America,where a double-slab configuration with complex tearing has recently been observed.We reproduce the subduction history of the Cocos slab since the Eocene.During this period,multiple episodes of tearing occurred within the Cocos slab,starting at 25 Ma.We find that the ancient Farallon slab,subducted during the Mesozoic,enhances the lateral pressure gradient across the slab hinge,promoting eastward mantle flow and tearing of the Cocos slab.The repeated tearing and subduction of the young Cocos plate have shaped the complex slab configuration in the region.
基金the National Supercomputer Center in Tianjin for their patient assistance in providing the compilation environment.We thank the editor,Huajian Yao,for handling the manuscript and Mingming Li and another anonymous reviewer for their constructive comments.The research leading to these results has received funding from National Natural Science Foundation of China projects(Grant Nos.92355302 and 42121005)Taishan Scholar projects(Grant No.tspd20210305)others(Grant Nos.XDB0710000,L2324203,XK2023DXC001,LSKJ202204400,and ZR2021ZD09).
文摘The thermal evolution of the Earth’s interior and its dynamic effects are the focus of Earth sciences.However,the commonly adopted grid-based temperature solver is usually prone to numerical oscillations,especially in the presence of sharp thermal gradients,such as when modeling subducting slabs and rising plumes.This phenomenon prohibits the correct representation of thermal evolution and may cause incorrect implications of geodynamic processes.After examining several approaches for removing these numerical oscillations,we show that the Lagrangian method provides an ideal way to solve this problem.In this study,we propose a particle-in-cell method as a strategy for improving the solution to the energy equation and demonstrate its effectiveness in both one-dimensional and three-dimensional thermal problems,as well as in a global spherical simulation with data assimilation.We have implemented this method in the open-source finite-element code CitcomS,which features a spherical coordinate system,distributed memory parallel computing,and data assimilation algorithms.
基金supported by the Strategy Priority Research Program(Category B)of the Chinese Academy of Sciences(Grant No.XDB0710000)the National Natural Science Foundation of China(Grant No.92355302)。
文摘1.Introduction The lithosphere is a fundamental component of Earth’s layered structure,and its stress state and deformation mechanisms are critical to understanding Earth’s tectonic evolution(Ghosh and Holt,2012)and managing natural resources(Heidbach et al.,2018).According to the classical theory of plate tectonics,significant lithospheric deformation is expected near active plate boundaries due to the relative motion between tectonic plates.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA22050103)the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(2022QNLM050201)and the National Natural Science Foundation of China(92258303)to W.S.L.L.acknowledges NSF grant EAR1554554.
文摘The Hawaiian-Emperor seamount chain has shown two subparallel geographical and geochemical volcanic trends,Loa and Kea,since-5 Ma,for which numerous models have been proposed that usually involve a single mantle plume sampling different compositional sources of the deep or shallow mantle.However,both the dramatically increased eruption rate of the Hawaiian hotspot since-5 Ma and the nearly simultaneous southward bending of the Hawaiian chain remain unexplained.
