scholarly journals Crustal anisotropy in the Ural Mountains Foredeep from teleseismic receiver functions

1997 ◽  
Vol 24 (11) ◽  
pp. 1283-1286 ◽  
Author(s):  
Vadim Levin ◽  
Jeffrey Park
Keyword(s):  
Receiver Functions ◽  
Ural Mountains ◽  
Crustal Anisotropy

Crustal Anisotropy beneath Northern Iran calculated by harmonic decomposition of Receiver Functions.

2020 ◽  
Author(s):  
Mohsen Azqandi ◽  
Mohammad Reza Abbassi ◽  
Meysam Mahmoodabadi ◽  
Ahmad Sadidkhouy
Keyword(s):  
Receiver Function ◽  
Receiver Functions ◽  
Upper Crust ◽  
Northern Iran ◽  
Crustal Anisotropy ◽  
Principal Stress Direction ◽  
South Central ◽  
Stress Direction ◽  
Harmonic Decomposition ◽  
Time Variations

<p>This study concerns crustal anisotropy at 16 permanent seismic stations to investigate preferentially aligned cracks or structures and their relation to the stress-state in the South Central Alborz (northern Iran). We consider plunging anisotropy and dipping interfaces of multiple layers using harmonic functions to correct the arrival time variations of <em>Ps</em> phases from different back-azimuths.</p><p>The dominant fast orientation of integrated crustal anisotropy strikes NE, almost parallel to the stress direction in the upper crust. The magnitude of crustal anisotropy is found to be in range of 0.1 s to 0.5 s. In some stations, intracrustal interface is observed, for which we analyzed harmonic decomposition of receiver functions to consider anisotropy in the upper crust. Upper crustal anisotropy strikes NE, close to the principal stress direction, indicating that stress in the upper crust plays a major role in producing anisotropy and deformation. In a few stations, crustal anisotropy display different directions rather than NE, which maybe controlled by cracks and fractures of dominant faults.</p><p>Keywords: Anisotropy, Receiver function, harmonic decomposition, Northern Iran.</p>

A Study on Crustal Anisotropy Using P to S Converted Phases of Receiver Functions: Application to Ailaoshan-Red River Fault Zone

2006 ◽  
Vol 49 (2) ◽  
pp. 383-393 ◽  
Author(s):  
Zhen XU ◽  
Ming-Jie XU ◽  
Liang-Shu WANG ◽  
Jian-Hua LIU ◽  
Kai ZHONG ◽  
...  
Keyword(s):  
Fault Zone ◽  
Receiver Functions ◽  
Red River ◽  
Crustal Anisotropy ◽  
Converted Phases ◽  
Red River Fault

scholarly journals Crustal anisotropy across northern Japan from receiver functions

2015 ◽  
Vol 120 (7) ◽  
pp. 4998-5012 ◽  
Author(s):  
I. Bianchi ◽  
G. Bokelmann ◽  
K. Shiomi
Keyword(s):  
Receiver Functions ◽  
Crustal Anisotropy ◽  
Northern Japan

Distribution of crustal azimuthalanisotropy beneath the North China Craton: Insights from analysis of receiver functions

2020 ◽  
Author(s):  
Tuo Zheng ◽  
S. Stephen Gao ◽  
Zhifeng Ding ◽  
Xiaoping Fan
Keyword(s):  
Fault Zone ◽  
North China Craton ◽  
North China ◽  
Receiver Functions ◽  
Azimuthal Anisotropy ◽  
Crustal Anisotropy ◽  
Near Surface ◽  
The North ◽  
Upper Mantle Anisotropy ◽  
Lithospheric Extension

<p>To characterize crustal anisotropy beneath the North China Craton (NCC), we apply a recently developed deconvolution approach to effectively remove near-surface reverberations in the receiver functions recorded at 200 broadband seismic stations and subsequently determine the fast orientation and the magnitude of crustal azimuthal anisotropy by fitting the sinusoidal moveout of the P to S converted phases from the Moho and intracrustal discontinuities. The magnitude of crustal anisotropy is found to range from 0.06 s to 0.54 s, with an average of 0.25 ± 0.08 s. Fault-parallel anisotropy in the seismically active Zhangjiakou-Penglai Fault Zone is significant and could be related to fluid-filled fractures. Historical strong earthquakes mainly occurred in the fault zone segments with significant crustal anisotropy, suggesting that the measured crustal anisotropy is closely related to the degree of crustal deformation. The observed spatial distribution of crustal anisotropy suggests that the northwestern terminus of the fault zone probably ends at about 114°E. Also observed is a sharp contrast in the fast orientations between the western and eastern Yanshan Uplifts separated by the North-South Gravity Lineament. The NW-SE trending anisotropy in the western Yanshan Uplift is attributable to “fossil” crustal anisotropy due to lithospheric extension of the NCC, while extensional fluid-saturated microcracks induced by regional compressive stress are responsible for the observed ENE-WSW trending anisotropy in the eastern Yanshan Uplift. Comparison of crustal anisotropy measurements and previously determined upper mantle anisotropy implies that the degree of crust-mantle coupling in the NCC varies spatially.</p>

The mantle flow below the Alps from isolated mantle anisotropy based on differential Ps – XKS Splitting

2020 ◽  
Author(s):  
Frederik Link ◽  
Georg Rümpker
Keyword(s):  
Receiver Function ◽  
Function Analysis ◽  
Receiver Functions ◽  
Model Parameters ◽  
Mantle Flow ◽  
European Alps ◽  
Crustal Anisotropy ◽  
Axis Orientation ◽  
The Alps ◽  
Mantle Anisotropy

<p>SKS-splitting measurements in the European Alps show an anisotropic fast axes parallel/subparallel relative to the mountain-belt. This indicates a mantle flow with a rotational component according to the orogeny under the assumption that the fast axes directly reflect the flow direction. This might be misleading due to a possible crustal contribution of anisotropy. Therefore, we isolate the crustal anisotropy using an improved receiver function method that accounts for anisotropic and structural properties.</p><p>The analysis for the crustal anisotropy is based on the stacking method proposed by Kaviani & Rümpker (2015). We modify their approach by introducing a time-selective splitting analysis of the crustal Ps- and PpPs-phases. The stacking is performed to the phases after correction of the anisotropic effect according to the model parameters H, the crustal thickness,  κ, the P-to S-wave velocity ratio, a, the percentage of anisotropy and φ, the fast axis orientation.</p><p>The Alps show a considerable Moho-topography due to its mountain root and its complex tectonic history. This can significantly deflect the crustal phases introducing a dominating appearance in the receiver functions. We therefore analyse for a dipping interface (not accounting for anisotropy) and then use an improved model in our analysis to infer the anisotropic properties of the crust.</p><p>Knowing the crustal anisotropic contribution we correct for this effect on the XKS-waveforms to isolate the anisotropy of the mantle. The remaining splitting shows an improved approximation of the flow patterns in the asthenosphere, while complexities might still imply an effect of the lithospheric mantle.</p><p>We apply our approach to stations of the AlpArray network resulting in a detailed distribution of the crustal anisotropy in the European Alps and show first results for the isolated mantle anisotropy from the corrected XKS-waveforms and the crustal anisotropy from the receiver-function analysis.</p>

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