Detachment folding of partially molten crust in accretionary orogens: A new magma-enhanced vertical mass and heat transfer mechanism

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F17%3A00483167" target="_blank" >RIV/67985530:_____/17:00483167 - isvavai.cz</a>

Alternative codes found

RIV/00025798:_____/17:00000052 RIV/00216208:11310/17:10370369

Result on the web

<a href="http://dx.doi.org/10.1130/L670.1" target="_blank" >http://dx.doi.org/10.1130/L670.1</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1130/L670.1" target="_blank" >10.1130/L670.1</a>

Result language

angličtina

Original language name

Detachment folding of partially molten crust in accretionary orogens: A new magma-enhanced vertical mass and heat transfer mechanism

Original language description

We use structural, petrographic, and geochronological data to examine processes of exhumation of partially molten crust in the Late Devonian-early Carboniferous Chandman dome in the Mongolian tract of the Central Asian Orogenic Belt. The dome is composed of a magmatite-migmatite core and a low-grade metamorphic envelope of early Paleozoic metasediments and Carboniferous clastics. Its tectonic evolution can be divided into three main stages. The oldest fabric is a subhorizontal foliation, S-1, in migmatites that is subparallel to the magmatic foliation in granitoids and to the greenschist facies schistosity in the enveloping metasediments. This event is interpreted as a result of horizontal deep crustal flow at depths of 20-25 km. The S-1 layering was subsequently transposed into a new foliation, S-2, or affected by open to close upright F-2 folds that are locally truncated by steep walls of diatexites, suggesting influx of partially molten crust into fold cores. The shallow-dipping magmatic foliation in granitoids is locally reworked by vertical magmatic to gneissic S-2 fabrics. Syn-S-2 metamorphic assemblages and synkinematic to postkinematic cordierite point to exhumation of the migmatites and granitoids from 20-25 km to similar to 10 km, and concomitant isobaric heating of the surrounding upper crust. New Ar-40/Ar-39 ages of 350-340 Ma from both the high-grade core and the metamorphic mantle overlap with previously published crystallization ages of 360-340 Ma, suggesting that magmatism and cooling in the upper crust are partly synchronous. Late syn-D-2, S-2-parallel leucogranite sheets crosscutting both the magmatic core and the mantling migmatites either exploit S-2 or crosscut horizontal S-1 fabrics. They are interpreted as brittle expulsion of magma during ongoing syn-D-2 exhumation.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10505 - Geology

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

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

Name of the periodical

Lithosphere

ISSN

1941-8264

e-ISSN

—

Volume of the periodical

9

Issue of the periodical within the volume

6

Country of publishing house

US - UNITED STATES

Number of pages

21

Pages from-to

889-909

UT code for WoS article

000417374300003

EID of the result in the Scopus database

2-s2.0-85035132515