Myrmekitic intergrowth of tourmaline and quartz in eclogite-hosting gneisses of the Tso Morari ultrahigh-pressure metamorphic terrane (Eastern Ladakh, India): a possible record of high-pressure conditions
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F19%3A73600638" target="_blank" >RIV/61989592:15310/19:73600638 - isvavai.cz</a>
Result on the web
<a href="http://dx.doi.org/10.1144/SP481-2017-167" target="_blank" >http://dx.doi.org/10.1144/SP481-2017-167</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1144/SP481-2017-167" target="_blank" >10.1144/SP481-2017-167</a>
Alternative languages
Result language
angličtina
Original language name
Myrmekitic intergrowth of tourmaline and quartz in eclogite-hosting gneisses of the Tso Morari ultrahigh-pressure metamorphic terrane (Eastern Ladakh, India): a possible record of high-pressure conditions
Original language description
Alkaline schorlitic tourmaline with domains of myrmekitic quartz and tourmaline intergrowths is reported for the first time from quartzo-feldspathic gneisses of the Tso Morari Crystalline Complex (TMCC), eastern Ladakh Himalaya. Except for schorlitic tourmaline, the brown-green dravitic tourmaline occurs in melanocratic layers of the gneiss. The schorlitic tourmaline contains REE-rich apatite, which is a typical mineral formed under high-pressure (HP) conditions. The observed myrmekite, marked by vermicular quartz and tourmaline intergrowths, was probably formed during decompression as a consequence of excess silica released from recrystallized tourmaline. The recalculated composition of the tourmaline with quartz myrmekite suggests that Si also occupied the tourmaline octahedral Z site during the HP regime. During decompression excess Si from this tourmaline was replaced by Mg and Fe3+. At an early stage of exhumation needle-shaped schorlitic tourmaline II and mosaic zoning were formed. The excess of silica and the structural disorder suggest that the Si-oversaturated tourmaline was stable at high-pressure-ultrahigh-pressure (HP-UHP) conditions. The greater stability of dravitic tourmaline compared to schorlitic tourmaline at HP conditions is evidently recorded at the TMCC. The tourmaline-bearing gneisses of the TMCC most probably shared the same metamorphic conditions during Tertiary collision of the Indian and Eurasian plates, similar to that observed for the associated UHP eclogites
Czech name
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Czech description
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Classification
Type
C - Chapter in a specialist book
CEP classification
—
OECD FORD branch
10505 - Geology
Result continuities
Project
<a href="/en/project/LO1305" target="_blank" >LO1305: Development of the center of advanced technologies and materials</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2019
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Book/collection name
Crustal Architecture and Evolution of the Himalaya-Karakoram-Tibet Orogen
ISBN
978-1-78620-403-5
Number of pages of the result
20
Pages from-to
175-194
Number of pages of the book
386
Publisher name
Geological Society Publishing House
Place of publication
London
UT code for WoS chapter
000505955200010