The Earth's Crust and Upper Mantle of the Western Part of the South Tien Shan and Adjacent Territories of the Turanian Platform According to the Data of Explosion Seismology

1983 ◽  
pp. 561-564
Author(s):  
F.KH. ZUNNUNOV
Keyword(s):  
Upper Mantle ◽  
Tien Shan ◽  
Earth’S Crust ◽  
The South ◽  
Crust And Upper Mantle ◽  
Earth's Crust

scholarly journals STRUCTURE OF THE EARTH’S CRUST AND UPPER MANTLE OF THE SOUTH SIKHOTE-ALIN FROM MAGNETOTELLURIC SOUNDING AND DENSITY MODELING

2020 ◽  
Vol 39 (6) ◽  
pp. 65-81
Author(s):  
V.B. Kaplun ◽  
◽  
M.Yu. Nosyrev ◽  
Keyword(s):  
Late Cretaceous ◽  
Upper Mantle ◽  
Three Dimensional ◽  
Earth’S Crust ◽  
Sikhote Alin ◽  
The South ◽  
Crust And Upper Mantle ◽  
Earth's Crust ◽  
Cretaceous Subduction ◽  
Density Modeling

Based on the results of correlation of geoelectric and density sections made on the three-dimensional inversion from three sections located in the South Sikhote-Alin, the distribution regularities were emerged in the electric and density parameters, the relations between them were established, and new data on the structure of the Earth’s crust and upper mantle in the region were obtained. An assumption was made of the association of some density and electric inhomogeneity in the upper mantle with the processes of the Late Cretaceous subduction.

scholarly journals A model of the deep structure of the Earth’s crust and upper mantle in the area of the Karymshinsky gold-ore cluster according to geophysical data (South Kamchatka)

Georesursy ◽  
2020 ◽  
Vol 22 (1) ◽  
pp. 63-72
Author(s):  
Alexandr G. Nurmukhamedov ◽  
Mikhail D. Sidorov ◽  
Yury F. Moroz
Keyword(s):  
Upper Mantle ◽  
Deep Structure ◽  
Hydrothermal Systems ◽  
Earth’S Crust ◽  
The South ◽  
Converted Wave ◽  
Crust And Upper Mantle ◽  
Gold Ore ◽  
Dominant Feature ◽  
Earth's Crust

In the South of Kamchatka, modern geodynamic processes are actively taking place. A deep geological and geophysical model of the structure of the Earth’s crust and upper mantle along the regional profile of the Apacha Village-Mutnaya Bay in the zone of Tolmachevsky active magmatic center is presented. The profile passes near the South-Western border of the Karymshinskaya volcano-tectonic structure (VTS) and crosses the Ahomtenskaya VTS. The model created on the basis of integrated interpretation of materials of the earthquake converted-wave method (ECWM), gravity and magnetotelluric sounding (MTS). The thickness of the Earth’s crust along the profile varies from 30-33 km at the edges reaching 44-46 km, in its central part. The dominant feature of the model is a high-density formation – a block of the Earth’s crust, saturated with intrusions of the main and ultrabasic composition. The formation of the block is associated with a permeable zone between the crust and the upper mantle. In the block correlation of seismic boundaries is disturbed and in a density model the area with massive heterogeneity is allocated. A significant increase in depth to the M-Boundary in the center of the model is explained by the presence of a “bloated” transition layer between bark and mantle in this place. The thickness of the layer is about 10 km, and the density of the mantle reaches 3.4 g/cm3. It is assumed that this is a site of eklogization of breeds in a zone of paleosubduction of oceanic lithosphere under a continental. The area is favorable for the accumulation of meteor waters, which are in contact with high-temperature environment and postmagmatic solutions of intrusions, which leads to the formation of hydrothermal systems. The genetic connection of Karymshinsky gold-ore cluster with the intrusive array of medium-sour composition, allocated in the zone of the Tolmachevsky active Magmatic Center is shown.

A study of the Earth's crust and upper mantle using travel times and spectrum characteristics of body waves

1970 ◽  
Vol 60 (6) ◽  
pp. 1921-1935
Author(s):  
B. M. Gurbuz
Keyword(s):  
Upper Mantle ◽  
Body Waves ◽  
Earth’S Crust ◽  
Travel Times ◽  
Time Data ◽  
Crust And Upper Mantle ◽  
Contour Maps ◽  
Spectrum Characteristics ◽  
Earth's Crust ◽  
Early Rise

Abstract The aim of this paper is to investigate the velocity distribution and structure of the Earth's crust and upper mantle from the close collaboration of theory and experimental results of travel times and spectrum characteristics of body waves. The interpretation was based on 38 seismic records which were obtained from the “Project Early Rise” experiment during July 1966. The results refer to the area bounded by latitudes 49°W and 51°30′ and longitudes 93°W and 98°W. A least-squares analysis of the travel-time data was made and the uncertainties of the slopes, intercept times, and corresponding velocities were determined. The observed wide-angle reflections were used to calculate the root mean square velocities applying the T2 - X2 method. Depth calculations for the velocity discontinuities and seismic depth contour maps were made. A model was constructed, and the validity of the proposed new model was tested by comparing the observed travel times, spectrum-amplitude ratios, and relative phase shifts of body waves with theoretically expected values. Evidence is given for three discontinuities in the Earth's crust with velocities of 6.11 ± 0.01 km/sec, 6.8 ± 0.08 km/sec, and 7.10 ± 0.04 km/sec at average depths 18 ± 2 km and 25.5 ± 0.9 km. Velocities in the uppermost part of the mantle were determined as 7.90 ± 0.05 km/sec and 8.48 ± 0.05 km/sec with interfaces at the average depths of 34 ± 1 km, and 47 ± 1 km, respectively.

Sign in / Sign up

Export Citation Format

Share Document