Numerical modeling of three-dimensional convection in the upper mantle of the earth beneath Eurasia lithosphere

2014 ◽  
Vol 23 (2) ◽  
pp. 105-111 ◽  
Author(s):  
V. V. Chervov ◽  
G. G. Chernykh
2019 ◽  
pp. 180-198
Author(s):  
V. P. Trubitsyn

Global geodynamics is determined by thermal convection in the mantle which manifests itself on the surface by movements, relief, heat flow, and volcanism. Thermal convection in the Earth is complicated by the fact that the lithosphere is broken into rigid plates, the crust is broken into six separate floating continents and a number of islands, on the mantle bottom there are two giant piles of heavy material, at high convection intensity the ascending convective flows acquire a plume shape, and phase transformations take place in the mantle. The impacts of many factors on the mantle structure have been thoroughly studied and fairly well understood. It is pertinent to reconcile the new data on phase transformations at depths of 650 to 700 km with the seismic data on the positions of these boundaries. The ultimate problem of global geodynamics has not yet been solved; the three-dimensional structure of the whole-mantle flows, consistent with the observations in geophysics, geochemistry, geology, and numerical modeling, is not known even on a semischematic level.


Author(s):  
Lianjie Li ◽  
Jianxin Li ◽  
Haibo Xie ◽  
Hongqiang Liu ◽  
Li Sun ◽  
...  

2015 ◽  
Vol 33 (11) ◽  
pp. 1350-1359 ◽  
Author(s):  
Jonathan H. Perez ◽  
Fumina Tanaka ◽  
Fumihiko Tanaka ◽  
Daisuke Hamanaka ◽  
Toshitaka Uchino

1971 ◽  
Vol 61 (5) ◽  
pp. 1441-1451
Author(s):  
R. D. Adams

abstract Early reflections of the phase P′P′ recorded at North American seismograph stations from nuclear explosions in Novaya Zemlya are used to examine the crust and upper mantle beneath a region of eastern Antarctica. Many reflections are observed from depths less than 120 km, indicating considerable inhomogeneity at these depths in the Earth. No regular horizons were found throughout the area, but some correlation was observed among reflections at closely-spaced stations, and, at many stations, reflections were observed from depths of between 60 and 80 km, corresponding to a likely upper boundary of the low-velocity channel. Deeper reflections were found at depths of near 420 and 650 km. The latter boundary was particularly well-observed and appears to be sharply defined at a depth that is constant to within a few kilometers. The boundary at 420 km is not so well defined by reflections of P′P′, but reflects well longer-period PP waves, arriving at wider angles of incidence. This boundary appears to be at least as pronounced, but not so sharp as that near 650 km. The deep structure beneath Antarctica presents no obvious difference from that beneath other continental areas.


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