Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, Kyrgyzstan
The high- to ultrahigh-pressure metamorphic rocks of the Atbashy complex were petrologically investigated. The eclogites of the Choloktor Formation show a prograde evolution from epidote-blueschist facies (P = 17–21 kbar and T = 450–515 °C) to peak eclogite-UHP conditions (P = 26–29 kbar and T = 545...
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Elsevier
2018-11-01
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Series: | Geoscience Frontiers |
Online Access: | http://www.sciencedirect.com/science/article/pii/S1674987117301998 |
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Article |
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DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Maksatbek Satybaev Lin Ding Akira Takasu Apas Bakirov Kadyrbek Sakiev Fulong Cai Rustam Orozbaev Azamat Bakirov Janybek Baslakunov |
spellingShingle |
Maksatbek Satybaev Lin Ding Akira Takasu Apas Bakirov Kadyrbek Sakiev Fulong Cai Rustam Orozbaev Azamat Bakirov Janybek Baslakunov Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, Kyrgyzstan Geoscience Frontiers |
author_facet |
Maksatbek Satybaev Lin Ding Akira Takasu Apas Bakirov Kadyrbek Sakiev Fulong Cai Rustam Orozbaev Azamat Bakirov Janybek Baslakunov |
author_sort |
Maksatbek Satybaev |
title |
Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, Kyrgyzstan |
title_short |
Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, Kyrgyzstan |
title_full |
Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, Kyrgyzstan |
title_fullStr |
Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, Kyrgyzstan |
title_full_unstemmed |
Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, Kyrgyzstan |
title_sort |
petrology of metamorphic rocks from the atbashy complex, southern tien-shan, kyrgyzstan |
publisher |
Elsevier |
series |
Geoscience Frontiers |
issn |
1674-9871 |
publishDate |
2018-11-01 |
description |
The high- to ultrahigh-pressure metamorphic rocks of the Atbashy complex were petrologically investigated. The eclogites of the Choloktor Formation show a prograde evolution from epidote-blueschist facies (P = 17–21 kbar and T = 450–515 °C) to peak eclogite-UHP conditions (P = 26–29 kbar and T = 545–615 °C) with a subsequent epidote-amphibolite and greenschist facies overprint. The mica-schists of the Choloktor Formation also show a clockwise P-T path from blueschist/epidote-blueschist facies conditions through peak eclogite facies conditions (P = 21–23 kbar and T = 530–580 °C) to retrograde epidote-amphibolite and greenschist facies stages. A comparison of the P-T paths in the eclogites and mica-schists of Choloktor Formation reveal that they may have shared their P-T history from peak to retrograde stages. The mica-schists of the Atbashy Formation record peak metamorphism of P = 10–12 kbar and T = 515–565 °C, which indicates that the highest grade of regional metamorphism in the Atbashy Ridge was epidote-amphibolite facies.The newly obtained P-T conditions for the mica-schists of Choloktor Formation indicate that sheets of sedimentary rocks were brought to great depths along the subduction zone and they metamorphosed under eclogite facies HP conditions. The eclogite blocks were amalgamated with mica-schists of Choloktor Formation in the eclogite facies HP conditions and together they experienced isothermal decompression to ∼40 km. During this path, the eclogites and mica-schists of Choloktor Formation docked with mica-schists of Atbashy Formation at 10–12 kbar and 515–565 °C, and from this depth (∼40 km) the whole sequence was exhumed together. These new results improve our understanding of high-pressure metamorphism in subduction-related accretionary prism zones and the exhumation processes of deeply-seated rocks in the Atbashy HP-UHP complex. Keywords: Eclogite, Mica-schists, P-T conditions, Atbashy, Kyrgyz Tien-Shan |
url |
http://www.sciencedirect.com/science/article/pii/S1674987117301998 |
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doaj-2efc968d8a8045c0b2a3089ebe2166332020-11-24T21:47:54ZengElsevierGeoscience Frontiers1674-98712018-11-019617951807Petrology of metamorphic rocks from the Atbashy complex, Southern Tien-Shan, KyrgyzstanMaksatbek Satybaev0Lin Ding1Akira Takasu2Apas Bakirov3Kadyrbek Sakiev4Fulong Cai5Rustam Orozbaev6Azamat Bakirov7Janybek Baslakunov8Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Geology, National Academy of Sciences, 30 Erkindik, Bishkek 720040, Kyrgyzstan; Corresponding author. Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China.Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, ChinaDepartment of Geoscience, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, JapanInstitute of Geology, National Academy of Sciences, 30 Erkindik, Bishkek 720040, KyrgyzstanInstitute of Geology, National Academy of Sciences, 30 Erkindik, Bishkek 720040, KyrgyzstanKey Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, ChinaInstitute of Geology, National Academy of Sciences, 30 Erkindik, Bishkek 720040, Kyrgyzstan; Research Center for Ecology and Environment of Central Asia (Bishkek), 30 Erkindik, Bishkek 720040, KyrgyzstanInstitute of Geology, National Academy of Sciences, 30 Erkindik, Bishkek 720040, KyrgyzstanInstitute of Geology, National Academy of Sciences, 30 Erkindik, Bishkek 720040, KyrgyzstanThe high- to ultrahigh-pressure metamorphic rocks of the Atbashy complex were petrologically investigated. The eclogites of the Choloktor Formation show a prograde evolution from epidote-blueschist facies (P = 17–21 kbar and T = 450–515 °C) to peak eclogite-UHP conditions (P = 26–29 kbar and T = 545–615 °C) with a subsequent epidote-amphibolite and greenschist facies overprint. The mica-schists of the Choloktor Formation also show a clockwise P-T path from blueschist/epidote-blueschist facies conditions through peak eclogite facies conditions (P = 21–23 kbar and T = 530–580 °C) to retrograde epidote-amphibolite and greenschist facies stages. A comparison of the P-T paths in the eclogites and mica-schists of Choloktor Formation reveal that they may have shared their P-T history from peak to retrograde stages. The mica-schists of the Atbashy Formation record peak metamorphism of P = 10–12 kbar and T = 515–565 °C, which indicates that the highest grade of regional metamorphism in the Atbashy Ridge was epidote-amphibolite facies.The newly obtained P-T conditions for the mica-schists of Choloktor Formation indicate that sheets of sedimentary rocks were brought to great depths along the subduction zone and they metamorphosed under eclogite facies HP conditions. The eclogite blocks were amalgamated with mica-schists of Choloktor Formation in the eclogite facies HP conditions and together they experienced isothermal decompression to ∼40 km. During this path, the eclogites and mica-schists of Choloktor Formation docked with mica-schists of Atbashy Formation at 10–12 kbar and 515–565 °C, and from this depth (∼40 km) the whole sequence was exhumed together. These new results improve our understanding of high-pressure metamorphism in subduction-related accretionary prism zones and the exhumation processes of deeply-seated rocks in the Atbashy HP-UHP complex. Keywords: Eclogite, Mica-schists, P-T conditions, Atbashy, Kyrgyz Tien-Shanhttp://www.sciencedirect.com/science/article/pii/S1674987117301998 |