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1、Institute of Ore Deposits Geology, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences, Staromonetnyi per., 35, Moscow 109017,Journal of Asian Earth Sciences 23 (2004) 605–627www.elsevier.com/locate/jseaesIsotope provinces, mechanisms of generation and sourcesof the continental c
2、rust in the Central Asian mobile belt: geologicaland isotopic evidenceV.I. Kovalenkoa, V.V. Yarmolyuka, V.P. Kovachb,*, A.B. Kotovb, I.K. Kozakovb,E.B. Salnikovab, A.M. LarinbaRussian FederationbInstitute of Precambrian Geology and Geochronology, Russian Academy of Sciences, Makarova emb., 2, St-
3、 Petersburg 199034, Russian FederationAbstractThe available geological, geochronological and isotopic data on the felsic magmatic and related rocks from South Siberia, Transbaikaliaand Mongolia are summarized to improve our understanding of the mechanisms and processes of the Phanerozoic crustal g
4、rowth in theCentral Asian mobile belt (CAMB). The following isotope provinces have been recognised: ‘Precambrian’ (TDM ¼ 3:3 –2:9 and 2.5–0.9 Ga)at the microcontinental blocks, ‘Caledonian’ (TDM ¼ 1.1–0.55 Ga), ‘Hercynian’ (TDM ¼ 0.8–0.5 Ma) and ‘Indosinian’ (TDM ¼ 0.3 Ga) thatcoincide with coeval
5、 tectonic zones and formed at 570–475, 420–320 and 310–220 Ma. Continental crust of the microcontinents isunderlain by, or intermixed with, ‘juvenile’ crust as evidenced by its isotopic heterogeneity. The continental crust of the Caledonian,Hercynian and Indosinian provinces is isotopically homoge
6、neous and was produced from respective juvenile sources with addition of oldcrustal material in the island arcs or active continental margin environments. The crustal growth in the CAMB had episodic character andimportant crust-forming events took place in the Phanerozoic. Formation of the CAMB wa
7、s connected with break up of the Rodiniasupercontinent in consequence of creation of the South-Pacific hot superplume. Intraplate magmatism preceding and accompanyingpermanently other magmatic activity in the CAMB