Geochemistry of the Eocene magmatic rocks from the Lesser Caucasus area (Armenia): evidence of a subduction geodynamic environment

2016 ◽  
Vol 428 (1) ◽  
pp. 73-98 ◽  
Author(s):  
L. Sahakyan ◽  
D. Bosch ◽  
M. Sosson ◽  
A. Avagyan ◽  
Gh. Galoyan ◽  
...  
Keyword(s):  
Magmatic Rocks ◽  
Geodynamic Environment ◽  
Lesser Caucasus

STRIKE-SLIP FAULTING DOMINATES THE RESPONSE OF THE LESSER CAUCASUS TO THE ARABIA-EURASIA CONTINENT COLLISION

2018 ◽  
Author(s):  
Nikolas C. Midttun ◽  
◽  
Nathan A. Niemi ◽  
Hektor Babayan ◽  
Hayk Igityan ◽  
...  
Keyword(s):  
Strike Slip ◽  
Lesser Caucasus

Supplemental Material: Tectonic origin of the Bainaimiao arc terrane in the southern Central Asian orogenic belt: Evidence from sedimentary and magmatic rocks in the Damao region

2020 ◽  
Author(s):  
Hai Zhou ◽  
Guochun Zhao ◽  
et al.
Keyword(s):  
Volcanic Rocks ◽  
Orogenic Belt ◽  
Central Asian Orogenic Belt ◽  
Isotopic Data ◽  
Magmatic Rocks ◽  
Central Asian ◽  
Southern Central ◽  
Samples And Sampling ◽  
Tectonic Origin

Table S1: Summary of the samples and sampling positions in this study (sampling sites are marked in Fig. 3); Table S2: U-Pb age data for zircons of (meta-)sedimentary and volcanic rocks in this study; Table S3: Lu-Hf isotopic data for zircons of (meta-)sedimentary and volcanic rocks in this study.

scholarly journals Partially open grain and phase boundaries as fluid pathways in metamorphic and magmatic rocks

2021 ◽  
Author(s):  
Richard Wirth ◽  
Jörn H. Kruhl ◽  
Luiz F.G. Morales ◽  
Anja Schreiber
Keyword(s):  
Phase Boundaries ◽  
Magmatic Rocks

scholarly journals Petrogenesis and Geodynamic Implications of Miocene Felsic Magmatic Rocks in the Wuyu Basin, Southern Gangdese Belt, Qinghai-Tibet Plateau

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 655
Author(s):  
Hanzhi Chen ◽  
Mingcai Hou ◽  
Fuhao Xiong ◽  
Hongwei Tang ◽  
Gangqiang Shao
Keyword(s):  
Lower Crust ◽  
Volcanic Rocks ◽  
Tibet Plateau ◽  
Southern Tibet ◽  
Mixed Product ◽  
Good Opportunity ◽  
Magmatic Rocks ◽  
Adakitic Rocks ◽  
Felsic Volcanic ◽  
Qinghai Tibet Plateau

Miocene felsic magmatic rocks with high Sr/Y ratios are widely distributed throughout the Gangdese belt of southern Tibet. These provide a good opportunity to explore the magmatic process and deep dynamic mechanisms that occurred after collision between the Indo and the Asian plates. In this paper, felsic volcanic rocks from the Zongdangcun Formation in the Wuyu Basin in the central part of the southern Gangdese belt are used to disclose their origin. Zircon U-Pb geochronology analysis shows that the felsic magmatism occurred at ca. 10.3 ± 0.2 Ma, indicating that the Zongdangcun Formation formed during the Miocene. Most of these felsic magmatic rocks plot in the rhyolite area in the TAS diagram. The rhyolite specimens from the Zongdangcun Formation have the characteristics of high SiO2 (>64%), K2O, SiO2, and Sr contents, a low Y content and a high Sr/Y ratio, and the rocks are rich in LREE and depleted in HREE, showing geochemical affinity to adakitic rocks. The rocks have an enriched Sr-Nd isotopic composition (εNd(t) = −6.76 to −6.68, (87Sr/86Sr)i = 0.7082–0.7088), which is similar to the mixed product of the juvenile Lhasa lower continental crust and the ancient Indian crust. The Hf isotopes of zircon define a wide compositional range (εHf(t) = −4.19 to 6.72) with predominant enriched signatures. The Miocene-aged crustal thickness in southern Tibet, calculated on the basis of the Sr/Y and (La/Yb)N ratios was approximately 60–80 km, which is consistent with the thickening of the Qinghai-Tibet Plateau. The origin of Miocene felsic magmatic rocks with high Sr/Y ratios in the middle section of the Gangdese belt likely involved a partial melting of the thickened lower crust, essentially formed by the lower crust of the Lhasa block, with minor contribution from the ancient Indian crust. After comprehensively analyzing the post-collisional high Sr/Y magmatic rocks (33–8 Ma) collected from the southern margin of the Gangdese belt, we propose that the front edge tearing and segmented subduction of the Indian continental slab may be the major factor driving the east-west trending compositional changes of the Miocene adakitic rocks in southern Tibet.

40Ar/39Ar age and petrology of magmatic rocks from East Balkan (Bulgaria) constrain the initiation of regional subduction in SE Europe

Lithos ◽  
2021 ◽  
pp. 106302
Author(s):  
Svetoslav Georgiev ◽  
Peter Marchev ◽  
Brian Jicha ◽  
Banush Banushev ◽  
Raya Raicheva ◽  
...  
Keyword(s):  
Magmatic Rocks
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