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Petrogenesis of the late Cretaceous tholeiitic magmatism in the passive margins of northeastern Madagascar.
No full textThe Late Cretaceous Flood Basalt Province of Madagascar: geochemistry of lavas and dykes in the northeastern passive margins, and regional correlations.
No full textSpecial Pape
Petrogenesis of the late Cretaceous tholeiitic magmatism in the passive margins of northeastern Madagascar.
No full textPetrogenesis of the late Cretaceous tholeiitic magmatism in the passive margins of northeastern Madagascar.
No full textSpecial Paper 362, Magmatic rifted margin
The Late Cretaceous Flood Basalt Province of Madagascar: geochemistry of lavas and dykes in the northeastern passive margins, and regional correlations.
No full textSpecial Pape
The Late Cretaceous Flood Basalt Province of Madagascar: geochemistry of lavas and dykes in the northeastern passive margins, and regional correlations.
No full textSpecial Pape
The tholeiitic dyke swarm of the Arraial do Cabo peninsula (SE Brazil): 39Ar/40Ar ages, petrogenesis and regional significance.
No full textWe present 40Ar/39Ar age determinations and chemical and Sr–Nd isotopic data for the tholeiitic dyke swarm cropping out at Arraial do Cabo peninsula at the eastern end of the Rio de Janeiro coastline. The age determinations indicate that the swarm emplaced approximately 55 Ma ago and thus is similar in age to the K-rich alkaline dykes and plugs also found in the peninsula. The dykes are basalts and basaltic andesites that belong to low Ti tholeiitic series. One dyke group is basaltic in composition, has relatively low Zr/Nb (8.9±1.8), roughly flat mantle-normalized incompatible element patterns, relatively low initial 87Sr/86Sr (0.70434–0.70426), and high εNd(55) (+2.3 to +3.8). These dykes chemically resemble enriched midocean ridge basalts (MORB). A second dyke group is formed by more evolved basaltic andesites with higher Zr/Nb ratios (12.7±2.1), negative Nb anomalies in the mantle-normalized patterns, higher initial 87Sr/86Sr (0.70548–0.70613), and lower εNd(55) (−1.8 to −2.2). Chemical and isotopic data exclude the possibility that the two dyke types are comagmatic or related to each other through crustal contamination processes. The genesis of the Arraial do Cabo tholeiites was likely caused by extension-related melting of a largely incompatible element-depleted mantle, with no trace of the enriched component in the roughly coeval, K-rich mafic alkaline magmas of the Serra do Mar province
Petrogenesis of the late Cretaceous tholeiitic magmatism in the passive margins of northeastern Madagascar.
No full textSpecial Paper 362, Magmatic rifted margin
Chemical and isotopic (C, O, Sr, Nd) characteristics of the Xiluvo carbonatite (central-western Mozambique)
No full textGeochemical provinciality in the Cretaceous magmatism of northern Madagascar, and mantle source implications.
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