Mineralogical, petrological and geochemical aspects of alkaline and alkaline-carbonatite associations from Brazil

Morbidelli, L.; Gomes, Celso B.; Beccaluva, Luigi; Brotzu, P.; Conte, Aida Maria; Ruberti, Excelso; Traversa, G.

doi:10.1016/0012-8252(95)00031-3

Cited by 98 publications

(85 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…With heights generally greater than 800 m and broad lateral extension, the basaltic rocks on the plateau date to the Cretaceous and present a wide variation in the strontium isotope composition (0.705 to 0.713), revealing different degrees of crustal contamination (Mantovani et al 1985, Marques et al 1999. Meanwhile, the alkaline complexes are volcanic to sub-volcanic structures with localized occurrence and strontium isotope ratios of around 0.705 (Morbidelli et al 1995, Walter et al 1995, Huang et al 1995, Ruberti et al 2002. The alkaline complexes closest to Forte Marechal Luz are located in the municipalities of Juquiá, Jacupiranga, Cananéia, Tunas, Mato Preto, Barra do Itapirapuã, and Itapurapuã.…”

Section: Discussionmentioning

confidence: 99%

Human mobility on the Brazilian coast: an analysis of strontium isotopes in archaeological human remains from Forte Marechal Luz Sambaqui

Bastos¹,

Souza²,

Santos³

et al. 2011

An. Acad. Bras. Ciênc.

View full text Add to dashboard Cite

This study investigated strontium isotopes in the dental enamel of 32 human skeletons from Forte Marechal Luz sambaqui (shellmound), Santa Catarina, Brazil, aiming at identifying local and non-local individuals. The archeological site presents pot sherds in the uppermost archeological layers. Dental enamel was also examined from specimens of terrestrial fauna 87 Sr/ 86 Sr = 0.71046 to 0.71273 and marine fauna 87 Sr/ 86 Sr = 0.70917 . The 87 Sr/ 86 Sr isotope ratio for individuals classified as locals ranged from 0.70905 to 0.71064 and was closer to the isotope ratio of the seawater than to the ratio of the terrestrial fauna, indicating a strong influence of marine strontium on the inhabitants of this sambaqui. The results indicate the existence of three non-local individuals 87 Sr/ 86 Sr = 0.70761 to 0.70835 , buried in both the level without pottery and the layer with pottery, possibly originated from the Santa Catarina Plateau, close to the municipality of Lages, or from the Curitiba Plateau. The occurrence of a slight difference between the isotope ratios of local individuals buried in the archeological layer without pottery, when compared to those in the layer with pottery, suggests a possible change in dietary patterns between these two moments in the site's occupation.

show abstract

Section: Discussionmentioning

confidence: 99%

Human mobility on the Brazilian coast: an analysis of strontium isotopes in archaeological human remains from Forte Marechal Luz Sambaqui

Bastos¹,

Souza²,

Santos³

et al. 2011

An. Acad. Bras. Ciênc.

View full text Add to dashboard Cite

show abstract

“…The Ponte Nova massif (K-Ar, 87.6 Ma; Azzone et al 2009) is part of an extensive province of MesozoicCenozoic continental alkaline-carbonatitic magmatism spread over the central and southeastern regions of the Brazilian Platform (Almeida 1983, Morbidelli et al 1995. It is located in the northern sector of Serra do Mar Province (Riccomini et al 2005), which groups the Late Cretaceous alkaline occurrences of the western border of the Santos Basin (Fig.…”

Section: Geological Contextmentioning

confidence: 99%

“…The main model relative to the genesis of MesozoicCenozoic mafic to ultramafic alkaline magmas of southeastern Brazil is the partial melting of a heterogeneous subcontinental lithospheric mantle previously enriched in incompatible elements and volatile components by metasomatic events (Morbidelli et al 1995, Brotzu et al 1997, Enrich et al 2005, Gibson et al 1999, CominChiaramonti et al 2002.…”

Section: Implications Concerning the Mantle Sourcementioning

confidence: 99%

“…During Proterozoic times, subduction-driven environments related to the Gondwana agglomeration (Campos Neto 2000, Heilbron et al 2004) could have led to important modification of the lithospheric mantle. In addition, the distensive environment related to the breakup of Gondwana and the formation of the Atlantic ocean during Mesozoic times (Almeida 1983, Morbidelli et al 1995, could be related to other mantle metasomatic events.…”

Section: Implications Concerning the Mantle Sourcementioning

confidence: 99%

See 1 more Smart Citation

Zr- AND Ba-RICH MINERALS FROM THE PONTE NOVA ALKALINE MAFIC-ULTRAMAFIC MASSIF, SOUTHEASTERN BRAZIL: INDICATION OF AN ENRICHED MANTLE SOURCE

Azzone

Ruberti

Enrich

et al. 2009

The Canadian Mineralogist

Self Cite

View full text Add to dashboard Cite

Zirconium-and Ba-rich minerals are found in gabbroic rocks from the Ponte Nova alkaline mafic-ultramafic massif in southeastern Brazil. The unusual mineralogical assemblage includes zirconolite, baddeleyite, Ba-rich alkali feldspar, and Baand Ti-rich biotite. Zirconolite of the Ponte Nova massif has higher levels of Zr (up to 1.172 apfu) than those registered in other terrestrial rocks and a prominent enrichment in the light rare-earth elements. Baddeleyite contains small quantities of Hf, Ti, and Fe. The Ba-rich alkali feldspar and Ba-and Ti-rich biotite contain up to 9.25 and 7.35 wt% BaO, respectively, and the biotite contains up to 12.01 wt% TiO 2 . In the different intrusions of the Ponte Nova massif, such an unusual assemblage typifies the residual magma after the crystallization of clinopyroxene and olivine from previously enriched basanitic parental magma. The different trends of enrichments in REE and Th + U found for zirconolite of the intrusions of the Ponte Nova massif provide a better understanding of the variable degrees of enrichment of incompatible elements of the distinct gabbroic bodies. A lithospheric mantle source enriched in incompatible elements by the metasomatic action of volatile-rich fluids and with the presence of phlogopite or amphibole (or both) and other minor accessory phases could explain the presence of the Zr-and Ba-rich minerals in this gabbroic massif.

show abstract

“…1A; Almeida 1983, Thompson et al 1998, Riccomini et al 2005, Brotzu et al 2005. This province is part of an extensive Meso-Cenozoic tholeiitic-alkaline-carbonatitic magmatism that is spread over the central and southeastern regions of the Brazilian Platform (Morbidelli et al 1995, Peate 1997. Syenites and nepheline syenites of miaskitic affinity (i.e., nepheline syenites containing zircon or titanite or molar (Na 2 O+K 2 O)/Al 2 O 3 < 1 in bulk-rock composition; Sørensen 1997, Le Maitre 2002 prevail in many occurrences in the Serra do Mar Alkaline Province (Almeida 1983, Brotzu et al 2005.…”

Section: Magmatic Contextmentioning

confidence: 99%

Eudialyte-group minerals from the Monte de Trigo alkaline suite, Brazil: composition and petrological implications

et al. 2016

View full text Add to dashboard Cite

ABSTRACT:The Monte de Trigo alkaline suite is a SiO 2 -undersaturated syenite-gabbroid association from the Serra do Mar alkaline province. Eudialyte-group minerals (EGMs) occur in one nepheline microsyenite dyke, associated with aegirine-augite, wöhlerite, låvenite, magnetite, zircon, titanite, britholite, and pyrochlore. Major compositional variations include Si (25.09-25.57 apfu), Nb (0.31-0.76 apfu), Fe (1.40-2.13 apfu), and Mn (1.36-2.08 apfu). The EGMs also contain relatively high contents of Ca (6.13-7.10 apfu), moderate enrichment of rare earth elements (0.38-0.67 apfu), and a relatively low Na content (11.02-12.28 apfu), which can be correlated with their transitional agpaitic assemblage. EGM compositions indicate a complex solid solution that includes eudialyte, kentbrooksite, feklichevite, zirsilite-(Ce), georgbarsanovite, and manganoeudialyte components. EGM trace element analyses show low Sr and Ba contents and a negative Eu/Eu* anomaly, which are interpreted as characteristic of the parental magma due to the previous fractionation of plagioclase and/or alkali feldspar. The EGMs from the dyke border have higher contents of Fe, Sr (2,161-2,699 ppm), Mg (1,179-3,582 ppm), and Zn (732-852 ppm) than those at the dyke center. These differences are related to the incorporation of xenoliths and xenocrysts of melatheralitic host rock into the nephelinesyenitic magma followed by crystal-melt diffusive exchange.KEYWORDS: mineral chemistry; agpaitic rocks; Serra do Mar alkaline province. Ca (6,10 apfu), enriquecimento moderado de elementos terras raras (0,67 apfu) e concentrações relativamente baixas de Na (11,(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)28 de Fe, RESUMO: A suíte alcalina do Monte de Trigo é uma associação sienítico-gabroide que pertence à província alcalina da Serra do Mar. Minerais do grupo da eudialita (EGMs) ocorrem em um dique de nefelina microssienito associados a egirina-augita, wöhlerita, lavenita, magnetita, zircão, titanita, britolita e pirocloro. As principais variações composicionais incluem Si (25,09-25,57 apfu), Nb (0,31-0,76 apfu), Fe (1,40-2,13 apfu) e Mn (1,36-2,08 apfu). Os EGMs também contêm concentrações relativamente altas de

show abstract

Mineralogical, petrological and geochemical aspects of alkaline and alkaline-carbonatite associations from Brazil

Cited by 98 publications

References 29 publications

Human mobility on the Brazilian coast: an analysis of strontium isotopes in archaeological human remains from Forte Marechal Luz Sambaqui

Human mobility on the Brazilian coast: an analysis of strontium isotopes in archaeological human remains from Forte Marechal Luz Sambaqui

Zr- AND Ba-RICH MINERALS FROM THE PONTE NOVA ALKALINE MAFIC-ULTRAMAFIC MASSIF, SOUTHEASTERN BRAZIL: INDICATION OF AN ENRICHED MANTLE SOURCE

Eudialyte-group minerals from the Monte de Trigo alkaline suite, Brazil: composition and petrological implications

Contact Info

Product

Resources

About