Research output: Contribution to journal › Article › peer-review
Composition and u–Pb (LA-ICP-MS) isotopic age of zircons from composite dikes of western Sangilen (Tuva-Mongolian orogen). / Tsygankov, A. A.; Burmakina, G. N.; Yakovlev, V. A. et al.
In: Russian Geology and Geophysics, Vol. 60, No. 1, 01.01.2019, p. 45-66.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Composition and u–Pb (LA-ICP-MS) isotopic age of zircons from composite dikes of western Sangilen (Tuva-Mongolian orogen)
AU - Tsygankov, A. A.
AU - Burmakina, G. N.
AU - Yakovlev, V. A.
AU - Khubanov, V. B.
AU - Vladimirov, V. G.
AU - Karmysheva, I.
AU - Buyantuev, M. D.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Composite dikes (mingling dikes) of Western Sangilen (southeastern Tuva) are believed to indicate a shift from tectonic contraction, related to the mountain fold system formation, to postcollisional extension that ended with the disintegration of the collisional orogen. However, the position of composite dikes in the general sequence of magmatic events was based only on their geologic location and has not been confirmed by U/Pb isotope-geochronological data. The proposed study is concerned with the geologic structure, composition, and isotopic age (485–490 Ma) of West Sangilen composite dikes. The isotopic age of the host granites from the Matut pluton is 509 Ma; thermal events of Riphean (679–934 Ma) and early Paleozoic (484 Ma) age are reflected in zircons from gneiss-granites of the Erzin metamorphic complex. The obtained data are consistent with the earlier determined sequences of West Sangilen tectonometamorphic events. Basites from the examined composite dikes are strongly different in the contents of indicator elements (Rb, Nb, Ta, Zr, and Hf) and the Nb/Y, Zr/Y, Th/Ta, Zr/Nb, and Nb/Th ratios, which is indicative of different (probably, different-depth) mantle sources. The protolith of the salic component of the composite dikes might have been rocks similar in composition to the autochthonous/parautochthonous gneiss-granites of the Erzin metamorphic complex.
AB - Composite dikes (mingling dikes) of Western Sangilen (southeastern Tuva) are believed to indicate a shift from tectonic contraction, related to the mountain fold system formation, to postcollisional extension that ended with the disintegration of the collisional orogen. However, the position of composite dikes in the general sequence of magmatic events was based only on their geologic location and has not been confirmed by U/Pb isotope-geochronological data. The proposed study is concerned with the geologic structure, composition, and isotopic age (485–490 Ma) of West Sangilen composite dikes. The isotopic age of the host granites from the Matut pluton is 509 Ma; thermal events of Riphean (679–934 Ma) and early Paleozoic (484 Ma) age are reflected in zircons from gneiss-granites of the Erzin metamorphic complex. The obtained data are consistent with the earlier determined sequences of West Sangilen tectonometamorphic events. Basites from the examined composite dikes are strongly different in the contents of indicator elements (Rb, Nb, Ta, Zr, and Hf) and the Nb/Y, Zr/Y, Th/Ta, Zr/Nb, and Nb/Th ratios, which is indicative of different (probably, different-depth) mantle sources. The protolith of the salic component of the composite dikes might have been rocks similar in composition to the autochthonous/parautochthonous gneiss-granites of the Erzin metamorphic complex.
KW - Composite dikes
KW - Magma sources
KW - Mingling
KW - U–Pb isotopic age
KW - Western Sangilen
KW - Zircons
UR - http://www.scopus.com/inward/record.url?scp=85079488500&partnerID=8YFLogxK
U2 - 10.15372/RGG2019004
DO - 10.15372/RGG2019004
M3 - Article
VL - 60
SP - 45
EP - 66
JO - Russian Geology and Geophysics
JF - Russian Geology and Geophysics
SN - 1068-7971
IS - 1
ER -
ID: 23293031