Plate subduction drives both the internal convection and the surface geology of the solid Earth.Despite the rapid increase of computational power,it remains challenging for geodynamic models to reproduce the history o...Plate subduction drives both the internal convection and the surface geology of the solid Earth.Despite the rapid increase of computational power,it remains challenging for geodynamic models to reproduce the history of Earth-like subduction and associated mantle flow.Here,based on an adaptive approach of sequential data assimilation,we present a high-resolution global model since the mid-Mesozoic.This model incorporates the thermal structure and surface kinematics of tectonic plates based on a recent plate reconstruction to reproduce the observed subduction configuration and Earth-like convection.Introduction of temperature-and composition-dependent rheology allows for incorporation of many natural complexities,such as initiation of subduction zones,reversal of subduction polarity,and detailed plate-boundary dynamics.The resultant present-day slab geometry well matches Benioff zones and seismic tomography at depths < 1500 km,making it possible to hindcast past subduction dynamics and mantle flow.For example,the model produces a flat Farallon slab beneath North America during the Late Cretaceous to Early Cenozoic,a feature that has been geodynamically challenging to reproduce.This high-resolution model can also capture details of the 4-D evolution of slabs and the ambient mantle,such as temporally and spatially varying mantle flow associated with evolving slab geometry and buoyancy flux,as well as the formation of shallow slab tears due to subduction of young seafloors and the resulting complex mantle deformation.Such a geodynamic framework serves to further constrain uncertain plate reconstruction in the geological past,and to better understand the origin of enigmatic mantle seismic features.展开更多
The principle of habitable planets creation of near stars in our galaxy was developed. It was shown that the Earth and the Moon formed as a result of thermal nuclear explosion (TNE) after a collision with a small come...The principle of habitable planets creation of near stars in our galaxy was developed. It was shown that the Earth and the Moon formed as a result of thermal nuclear explosion (TNE) after a collision with a small comet. The comet has broken through the proto-Earth crust, and created conditions for liquid-drop division into the Earth and the Moon. It is shown that the comet impact on the proto-Earth led to formation of continents as well as to formation of the Moon, seas, oceans and atmosphere and to creation of conditions for life origin. The analysis of kimberlitic pipes distribution, as markers of comet fragments motion under a crust, shows that the comet has broken up under crust with formation of many gas bubbles. An analysis of the Martian topography revealed that the comet hit Mars not under a glancing angle. As a result, the products of TNE remained under the Marian crust. The track of the comet movement under the Venus crust was also established. It is shown that the planet surface near comet track is spotted by numerous cracks.展开更多
基金support from NSF grants EAR-1345135,1554554,1565640supercomputing allocation on Blue Waters through ACI-1516586
文摘Plate subduction drives both the internal convection and the surface geology of the solid Earth.Despite the rapid increase of computational power,it remains challenging for geodynamic models to reproduce the history of Earth-like subduction and associated mantle flow.Here,based on an adaptive approach of sequential data assimilation,we present a high-resolution global model since the mid-Mesozoic.This model incorporates the thermal structure and surface kinematics of tectonic plates based on a recent plate reconstruction to reproduce the observed subduction configuration and Earth-like convection.Introduction of temperature-and composition-dependent rheology allows for incorporation of many natural complexities,such as initiation of subduction zones,reversal of subduction polarity,and detailed plate-boundary dynamics.The resultant present-day slab geometry well matches Benioff zones and seismic tomography at depths < 1500 km,making it possible to hindcast past subduction dynamics and mantle flow.For example,the model produces a flat Farallon slab beneath North America during the Late Cretaceous to Early Cenozoic,a feature that has been geodynamically challenging to reproduce.This high-resolution model can also capture details of the 4-D evolution of slabs and the ambient mantle,such as temporally and spatially varying mantle flow associated with evolving slab geometry and buoyancy flux,as well as the formation of shallow slab tears due to subduction of young seafloors and the resulting complex mantle deformation.Such a geodynamic framework serves to further constrain uncertain plate reconstruction in the geological past,and to better understand the origin of enigmatic mantle seismic features.
文摘The principle of habitable planets creation of near stars in our galaxy was developed. It was shown that the Earth and the Moon formed as a result of thermal nuclear explosion (TNE) after a collision with a small comet. The comet has broken through the proto-Earth crust, and created conditions for liquid-drop division into the Earth and the Moon. It is shown that the comet impact on the proto-Earth led to formation of continents as well as to formation of the Moon, seas, oceans and atmosphere and to creation of conditions for life origin. The analysis of kimberlitic pipes distribution, as markers of comet fragments motion under a crust, shows that the comet has broken up under crust with formation of many gas bubbles. An analysis of the Martian topography revealed that the comet hit Mars not under a glancing angle. As a result, the products of TNE remained under the Marian crust. The track of the comet movement under the Venus crust was also established. It is shown that the planet surface near comet track is spotted by numerous cracks.
