Reply to: Comment on “Depleted and enriched mantle sources for Paleo- and Neoproterozoic carbonatites of southern India: Sr, Nd, C-O isotopic, and geochemical constraints”

2004 ◽  
Vol 213 (4) ◽  
pp. 435-436 ◽  
Author(s):  
M.K. Pandit ◽  
A.N. Sial ◽  
G.B. Sukumaran ◽  
M.M. Pimentel ◽  
A.K. Ramasamy ◽  
...  
Keyword(s):  
Southern India ◽  
Enriched Mantle ◽  
Mantle Sources ◽  
Geochemical Constraints

Depleted and enriched mantle sources for Paleo- and Neoproterozoic carbonatites of southern India: Sr, Nd, C–O isotopic and geochemical constraints

2002 ◽  
Vol 189 (1-2) ◽  
pp. 69-89 ◽  
Author(s):  
M.K Pandit ◽  
A.N Sial ◽  
G.B Sukumaran ◽  
M.M Pimentel ◽  
A.K Ramasamy ◽  
...  
Keyword(s):  
Southern India ◽  
Enriched Mantle ◽  
Mantle Sources ◽  
Geochemical Constraints

scholarly journals Ore and Geochemical Specialization and Substance Sources of the Ural and Timan Carbonatite Complexes (Russia): Insights from Trace Element, Rb–Sr, and Sm–Nd Isotope Data

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 711
Author(s):  
Irina Nedosekova ◽  
Nikolay Vladykin ◽  
Oksana Udoratina ◽  
Boris Belyatsky
Keyword(s):  
Trace Element ◽  
Mantle Source ◽  
Crustal Evolution ◽  
Trace Element Data ◽  
The Urals ◽  
Nd Isotope ◽  
Enriched Mantle ◽  
Depleted Mantle ◽  
Mantle Sources ◽  
Geochemical Specialization

The Ilmeno–Vishnevogorsk (IVC), Buldym, and Chetlassky carbonatite complexes are localized in the folded regions of the Urals and Timan. These complexes differ in geochemical signatures and ore specialization: Nb-deposits of pyrochlore carbonatites are associated with the IVC, while Nb–REE-deposits with the Buldym complex and REE-deposits of bastnäsite carbonatites with the Chetlassky complex. A comparative study of these carbonatite complexes has been conducted in order to establish the reasons for their ore specialization and their sources. The IVC is characterized by low 87Sr/86Sri (0.70336–0.70399) and εNd (+2 to +6), suggesting a single moderately depleted mantle source for rocks and pyrochlore mineralization. The Buldym complex has a higher 87Sr/86Sri (0.70440–0.70513) with negative εNd (−0.2 to −3), which corresponds to enriched mantle source EMI-type. The REE carbonatites of the Chetlassky сomplex show low 87Sr/86Sri (0.70336–0.70369) and a high εNd (+5–+6), which is close to the DM mantle source with ~5% marine sedimentary component. Based on Sr–Nd isotope signatures, major, and trace element data, we assume that the different ore specialization of Urals and Timan carbonatites may be caused not only by crustal evolution of alkaline-carbonatite magmas, but also by the heterogeneity of their mantle sources associated with different degrees of enrichment in recycled components.

Geochemical constraints on the Cenozoic, OIB-type alkaline volcanic rocks of NW Turkey: Implications for mantle sources and melting processes

Lithos ◽  
2006 ◽  
Vol 86 (1-2) ◽  
pp. 50-76 ◽  
Author(s):  
E. Aldanmaz ◽  
N. Köprübaşı ◽  
Ö.F. Gürer ◽  
N. Kaymakçı ◽  
A. Gourgaud
Keyword(s):  
Volcanic Rocks ◽  
Nw Turkey ◽  
Mantle Sources ◽  
Geochemical Constraints

scholarly journals Shona and Discovery Aseismic Ridge Systems, South Atlantic: Trace Element Evidence for Enriched Mantle Sources

2010 ◽  
Vol 51 (10) ◽  
pp. 2089-2120 ◽  
Author(s):  
A. le Roex ◽  
C. Class ◽  
J. O'Connor ◽  
W. Jokat
Keyword(s):  
Trace Element ◽  
South Atlantic ◽  
Enriched Mantle ◽  
Mantle Sources

Experimental study in the Na2O–CaO–MgO–Al2O3–SiO2–CO2 system at 3 GPa: the effect of sodium on mantle melting to carbonate-rich liquids and implications for the petrogenesis of silicocarbonatites

2012 ◽  
Vol 76 (2) ◽  
pp. 285-309 ◽  
Author(s):  
K. R. Moore
Keyword(s):  
Sodium Content ◽  
Silicate Melts ◽  
Monovalent Cations ◽  
Silicate System ◽  
Free System ◽  
Enriched Mantle ◽  
Mantle Sources ◽  
Analogue System ◽  
Carbonated Liquids ◽  
Metasomatized Mantle

AbstractMelt compositions in equilibrium with peridotite assemblages were determined in the analogue system Na2O–CaO–MgO–Al2O3–SiO2–CO2 at 3 GPa with Ca/Ca + Mg = 0.56–0.43 and up to 6 wt.% Na2O. There is a greater compositional range generated isobarically over a larger temperature interval than in a sodium-absent system: increasing sodium content drives liquids to compositions with lower CaO and higher SiO2 concentrations. A positive correlation between silica and Na2O content of liquids produced at constant temperature is due to the depolymerization of silicate tetrahedra in the presence of monovalent cations, as in the volatile-free system. Liquids with Na2O >6 wt.% occur in association with wehrlites as the composition of diopsidic pyroxene expands towards enstatite with addition of Na2O, decreasing the orthopyroxene content of peridotite. The orthopyroxene-out curve intersects an enriched mantle solidus at 3 GPa where near-solidus liquids have Na2O = 7 1.5 wt.%. Sodium partitioning between a metaluminous liquid and clinopyroxene follows the jadeite partitioning models calculated for the dry silicate system but sodium partitions into peralkaline carbonated liquids as both the pyroxene and the carbonate molecules. The peralkaline liquids generated are essentially carbonated silicate melts that are analogous to silica-bearing carbonatites and silicocarbonatites from a range of possible metasomatized mantle sources.

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