The Crust in the Pamir: Insights From Receiver Functions

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F19%3A00517415" target="_blank" >RIV/67985530:_____/19:00517415 - isvavai.cz</a>

Výsledek na webu

<a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019JB017765" target="_blank" >https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019JB017765</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2019JB017765" target="_blank" >10.1029/2019JB017765</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The Crust in the Pamir: Insights From Receiver Functions

Popis výsledku v původním jazyce

The Cenozoic convergence between India and Asia has created Earth's thickest crust in the Pamir-Tibet Plateau by extreme crustal shortening. Here we study the crustal structure of the Pamir and western Tian Shan, the adjacent margins of the Tajik, Tarim, and Ferghana Basins, and the Hindu Kush, using data collected by temporary seismic experiments. We derive, compare, and combine independent observations from P and S receiver functions. The obtained Moho depth varies from similar to 40 km below the basins to a double-normal thickness of 65-75 km underneath the Pamir and Hindu Kush. A Moho doublet-with the deeper interface down to a depth of similar to 90 km-coincides with the arc of intermediate-depth seismicity underneath the Pamir, where Asian continental lower crust delaminates and rolls back. The crust beneath most of the Central and South Pamir has a low V-p/V-s ratio (<1.70), suggesting a dominantly felsic composition, probably a result of delamination/foundering of the mafic rocks of the lower crust. Beneath the Cenozoic gneiss domes of the Central and South Pamir, which represent extensional core complexes, the V-p/V-s ratios are moderate to high (similar to 1.75), consistent with the previously observed, midcrustal low-velocity zones, implying the presence of crustal partial melts. Even higher crustal average V-p/V-s ratios up to 1.90 are found in the sedimentary basins and along the Main Pamir Thrust. The ratios along the latter-the active thrust front of the Pamir-may reflect fluid accumulations within a strongly fractured fault system.

Název v anglickém jazyce

The Crust in the Pamir: Insights From Receiver Functions

Popis výsledku anglicky

The Cenozoic convergence between India and Asia has created Earth's thickest crust in the Pamir-Tibet Plateau by extreme crustal shortening. Here we study the crustal structure of the Pamir and western Tian Shan, the adjacent margins of the Tajik, Tarim, and Ferghana Basins, and the Hindu Kush, using data collected by temporary seismic experiments. We derive, compare, and combine independent observations from P and S receiver functions. The obtained Moho depth varies from similar to 40 km below the basins to a double-normal thickness of 65-75 km underneath the Pamir and Hindu Kush. A Moho doublet-with the deeper interface down to a depth of similar to 90 km-coincides with the arc of intermediate-depth seismicity underneath the Pamir, where Asian continental lower crust delaminates and rolls back. The crust beneath most of the Central and South Pamir has a low V-p/V-s ratio (<1.70), suggesting a dominantly felsic composition, probably a result of delamination/foundering of the mafic rocks of the lower crust. Beneath the Cenozoic gneiss domes of the Central and South Pamir, which represent extensional core complexes, the V-p/V-s ratios are moderate to high (similar to 1.75), consistent with the previously observed, midcrustal low-velocity zones, implying the presence of crustal partial melts. Even higher crustal average V-p/V-s ratios up to 1.90 are found in the sedimentary basins and along the Main Pamir Thrust. The ratios along the latter-the active thrust front of the Pamir-may reflect fluid accumulations within a strongly fractured fault system.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10507 - Volcanology

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Geophysical Research: Solid Earth

ISSN

2169-9313

e-ISSN

—

Svazek periodika

124

Číslo periodika v rámci svazku

8

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

19

Strana od-do

9313-9331

Kód UT WoS článku

000491283500091

EID výsledku v databázi Scopus

2-s2.0-85070929050