The P and S wave velocity structures of the crust and upper mantle beneath Tibetan Plateau

1993 ◽  
Vol 6 (2) ◽  
pp. 299-304 ◽  
Author(s):  
Zhu Zhao ◽  
Rong-Sheng Zeng
Keyword(s):  
Tibetan Plateau ◽  
Wave Velocity ◽  
Upper Mantle ◽  
S Wave ◽  
Crust And Upper Mantle

Crust and Upper Mantle S-Wave Velocity Structure Across Northeastern Tibetan Plateau and Ordos Block

2005 ◽  
Vol 48 (2) ◽  
pp. 369-379 ◽  
Author(s):  
Jiu-Hui CHEN ◽  
Qi-Yuan LIU ◽  
Shun-Cheng LI ◽  
Biao GUO ◽  
Yuan-Gen LAI
Keyword(s):  
Tibetan Plateau ◽  
Wave Velocity ◽  
Upper Mantle ◽  
Velocity Structure ◽  
S Wave ◽  
Crust And Upper Mantle ◽  
Ordos Block ◽  
Northeastern Tibetan Plateau

Constraints on the composition of the crust and uppermost mantle in northwestern Canada: Vp/Vs variations along Lithoprobe's SNorCLE transect

2005 ◽  
Vol 42 (6) ◽  
pp. 1205-1222 ◽  
Author(s):  
Gabriela Fernández-Viejo ◽  
Ron M Clowes ◽  
J Kim Welford
Keyword(s):  
Wave Velocity ◽  
Upper Mantle ◽  
Laboratory Data ◽  
High Ratio ◽  
P Wave ◽  
S Wave ◽  
Uppermost Mantle ◽  
Crust And Upper Mantle ◽  
Slave Craton ◽  
Crustal Composition

Shear-wave seismic data recorded along four profiles during the SNoRE 97 (1997 Slave – Northern Cordillera Refraction Experiment) refraction – wide-angle reflection experiment in northwestern Canada are analyzed to provide S-wave velocity (Vs) models. These are combined with previous P-wave velocity (Vp) models to produce cross sections of the ratio Vp/Vs for the crust and upper mantle. The Vp/Vs values are related to rock types through comparisons with published laboratory data. The Slave craton has low Vp/Vs values of 1.68–1.72, indicating a predominantly silicic crustal composition. Higher values (1.78) for the Great Bear and eastern Hottah domains of the Wopmay orogen imply a more mafic than average crustal composition. In the western Hottah and Fort Simpson arc, values of Vp/Vs drop to ∼1.69. These low values continue westward for 700 km into the Foreland and Omineca belts of the Cordillera, providing support for the interpretation from coincident seismic reflection studies that much of the crust from east of the Cordilleran deformation front to the Stikinia terrane of the Intermontane Belt consists of quartzose metasedimentary rocks. Stikinia shows values of 1.78–1.73, consistent with its derivation as a volcanic arc terrane. Upper mantle velocity and ratio values beneath the Slave craton indicate an ultramafic peridotitic composition. In the Wopmay orogen, the presence of low Vp/Vs ratios beneath the Hottah – Fort Simpson transition indicates the presence of pyroxenite in the upper mantle. Across the northern Cordillera, low Vp values and a moderate-to-high ratio in the uppermost mantle are consistent with the region's high heat flow and the possible presence of partial melt.

A simple model of the crust and upper mantle in central Chile

1973 ◽  
Vol 63 (3) ◽  
pp. 819-825
Author(s):  
L. Chuaqui
Keyword(s):  
Wave Velocity ◽  
Upper Mantle ◽  
Structural Parameters ◽  
P Wave ◽  
S Wave ◽  
Crust And Upper Mantle ◽  
Central Chile ◽  
Arrival Times ◽  
P Wave Velocity ◽  
Wave Arrival

abstract A simplified model of the crust and upper mantle of central Chile is developed with P- and S-wave arrival times and is compared with previous gravimetric work on the area. The following structural parameters were determined: crustal P-wave velocity, upper mantle P-wave velocity, crustal thickness and orientation of the plane separating crust and upper mantle. The model obtained here agrees well with those calculated in the gravimetric study.

scholarly journals S wave Velocity Structure of the Crust and Upper Mantle Beneath Shanxi Rift, Central North China Craton and its Tectonic Implications

Tectonics ◽  
2021 ◽  
Vol 40 (4) ◽  
Author(s):  
Yan Cai ◽  
Jianping Wu ◽  
Andreas Rietbrock ◽  
Weilai Wang ◽  
Lihua Fang ◽  
...  
Keyword(s):  
Wave Velocity ◽  
Upper Mantle ◽  
North China Craton ◽  
North China ◽  
Velocity Structure ◽  
S Wave ◽  
Crust And Upper Mantle ◽  
Tectonic Implications ◽  
Shanxi Rift

scholarly journals Lithospheric structures of and tectonic implications for the central–east Tibetan plateau inferred from joint tomography of receiver functions and surface waves

2020 ◽  
Vol 223 (3) ◽  
pp. 1688-1707
Author(s):  
Mei Feng ◽  
Meijian An ◽  
James Mechie ◽  
Wenjin Zhao ◽  
Guangqi Xue ◽  
...  
Keyword(s):  
Surface Wave ◽  
Tibetan Plateau ◽  
Wave Velocity ◽  
Upper Mantle ◽  
High Velocity ◽  
Crustal Thickness ◽  
Receiver Functions ◽  
The Tibetan Plateau ◽  
S Wave ◽  
East Kunlun

SUMMARY We present an updated joint tomographic method to simultaneously invert receiver function waveforms and surface wave dispersions for a 3-D S-wave velocity (Vs) model. By applying this method to observations from ∼900 seismic stations and with a priori Moho constraints from previous studies, we construct a 3-D lithospheric S-wave velocity model and crustal-thickness map for the central–east Tibetan plateau. Data misfit/fitting shows that the inverted model can fit the receiver functions and surface wave dispersions reasonably well, and checkerboard tests show the model can retrieve major structural information. The results highlight several features. Within the plateau crustal thickness is >60 km and outwith the plateau it is ∼40 km. Obvious Moho offsets and lateral variations of crustal velocities exist beneath the eastern (Longmen Shan Fault), northern (central–east Kunlun Fault) and northeastern (east Kunlun Fault) boundaries of the plateau, but with decreasing intensity. Segmented high upper-mantle velocities have varied occurrences and depth extents from south/southwest to north/northeast in the plateau. A Z-shaped upper-mantle low-velocity channel, which was taken as Tibetan lithospheric mantle, reflecting deformable material lies along the northern and eastern periphery of the Tibetan plateau, seemingly separating two large high-velocity mantle areas that, respectively, correspond to the Indian and Asian lithospheres. Other small high-velocity mantle segments overlain by the Z-shaped channel are possibly remnants of cold microplates/slabs associated with subductions/collisions prior to the Indian–Eurasian collision during the accretion of the Tibetan region. By integrating the Vs structures with known tectonic information, we derive that the Indian slab generally underlies the plateau south of the Bangong–Nujiang suture in central Tibet and the Jinsha River suture in eastern Tibet and west of the Lanchangjiang suture in southeastern Tibet. The eastern, northern, northeastern and southeastern boundaries of the Tibetan plateau have undergone deformation with decreasing intensity. The weakly resisting northeast and southeast margins, bounded by a wider softer channel of uppermost mantle material, are two potential regions for plateau expansion in the future.

Structure of S-Wave Velocity in the Crust-Upper Mantle and Tectonic Setting of Strong Earthquakes Beneath Yunnan

2011 ◽  
Vol 54 (3) ◽  
pp. 286-298 ◽  
Author(s):  
Xiao-Man ZHANG ◽  
Jia-Fu HU ◽  
Yi-Li HU ◽  
Hai-Yan YANG ◽  
Jia CHEN ◽  
...  
Keyword(s):  
Wave Velocity ◽  
Upper Mantle ◽  
Tectonic Setting ◽  
S Wave ◽  
Strong Earthquakes
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