气候变化领域集成服务门户(CCPortal): Evidence of mingling between contrasting magmas in the Ribeirão do Óleo Pluton; Coastal Terrane and the tectonic implications on the Ribeira Belt; Brazil

CCPortal

DOI	10.1007/s00531-019-01804-9
	Evidence of mingling between contrasting magmas in the Ribeirão do Óleo Pluton; Coastal Terrane and the tectonic implications on the Ribeira Belt; Brazil
	Passarelli C.R.; Verma S.K.
发表日期	2020
ISSN	14373254
起始页码	317
结束页码	344
卷号	109 期号:1
英文摘要	Gneiss–migmatitic rocks and granites between the Cubatão and Itariri shear zones characterize the Mongaguá Complex-Coastal Terrane. Three major units are defined: (1) the Itariri Suite (IS) composed of monzogranites, granodiorites, tonalites, and locally gneiss–migmatitic rocks; (2) the Areado pluton composed of monzogranite and locally tonalite; and (3) the Ribeirão do Óleo Pluton mainly composed of monzogranites, which is the subject of this article. Combined field observations, petrography, Sr–Nd–Hf isotopes, U–Pb zircon data, and preliminary geochemical studies are presented for the Ribeirão do Óleo Pluton (ROP), intrusive in granite-gneisses of the IS. It is a plutonic association of weakly peraluminous, medium-to-high-K biotite monzogranites that surround microgranular intermediate enclaves, which are products of magma mingling. Different from the most examples of magma mingling described in the literature, the ROP mingling did not result from the intrusion of hot mafic magma into colder host felsic magma. Conversely, the emplacement of the monzogranite started most likely during the medium-to-final stage of crystallization of the quartz microdiorite. A detailed study of LA-ICP-MS U–Pb zircon ages, including zircon morphology and internal structure, was useful to determine more precisely the emplacement sequence and the relation between the units of the ROP. Intermediate and acid facies have Paleoproterozoic and Neoproterozoic inheritances, moreover a mixture of xenocrysts, antecrysts, and autocrysts, indicative of a complex evolution of the ROP. Several magma crystallization pulses are recorded at 655–624 Ma, 627–601 Ma, and 613–586 Ma. The negative εHf(t) ranging from − 17.26 to − 12.51 in monzogranites, εNd(t) values of − 10.66 to − 7.83 at t = 600 Ma in both facies, 87Sr/86Sr of ca. 0.708 for the monzogranite and 0.706 for the quartz microdiorite indicate a strong crustal contribution in the genesis of intermediate and acid magmas of this pluton. © 2020, Geologische Vereinigung e.V. (GV).
英文关键词	Coastal Terrane; LA-ICP-MS; Lu–Hf isotopes; Magma mingling; Ribeira Belt
语种	英语
scopus关键词	crystallization; emplacement; granite; hafnium; inductively coupled plasma method; lutetium; magma; pluton; tectonic setting; tonalite; Brazil; Ribeira Belt
来源期刊	International Journal of Earth Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/147727
作者单位	Instituto de Geociências, Universidade de São Paulo, Rua do Lago 562, Cidade Universitária, São Paulo, SP CEP 05508-080, Brazil; División de Geociencias Aplicadas, Instituto Potosino de Investigación Científica y Tecnológica, Col. Lomas 4a Sec., San Luis Potosí, SLP C.P. 78216, Mexico
推荐引用方式 GB/T 7714	Passarelli C.R.,Verma S.K.. Evidence of mingling between contrasting magmas in the Ribeirão do Óleo Pluton; Coastal Terrane and the tectonic implications on the Ribeira Belt; Brazil[J],2020,109(1).
APA	Passarelli C.R.,&Verma S.K..(2020).Evidence of mingling between contrasting magmas in the Ribeirão do Óleo Pluton; Coastal Terrane and the tectonic implications on the Ribeira Belt; Brazil.International Journal of Earth Sciences,109(1).
MLA	Passarelli C.R.,et al."Evidence of mingling between contrasting magmas in the Ribeirão do Óleo Pluton; Coastal Terrane and the tectonic implications on the Ribeira Belt; Brazil".International Journal of Earth Sciences 109.1(2020).