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TitreAge and tectonic setting of the Bavanat Cu-Zn-Ag Besshi-type volcanogenic massive sulfide deposit, southern Iran
AuteurMousivand, F; Rastad, E; Meffre, S; Peter, J M; Mohajjel, M; Zaw, K; Emami, M H
SourceMineralium Deposita vol. 47, issue 8, 2012 p. 911-931,
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110192
ÉditeurSpringer Verlag
Documentpublication en série
Mediapapier; en ligne; numérique
Formatsjpg; html; pdf
Lat/Long OENS 45.0000 60.0000 39.0000 32.0000
Sujetsminéralisation; cuivre; zinc; argent; gîtes volcanogènes; sulfures; gîtes sulfureux; gisements minéraux; datation au uranium-plomb; ophiolites; datation radiométrique; cadre tectonique; interprétations tectoniques; milieux tectoniques; lithogéochimie; tectonique; géochronologie; géologie économique; Mésozoïque; Jurassique
Illustrationslocation maps; stratigraphic columns; photographs; photomicrographs; plots; ternary diagrams; cross-sections
ProgrammeÉtude des gîtes de sulfures massifs volcaniques, Initiative géoscientifique ciblée (IGC-4)
Diffusé2012 03 08
Résumé(disponible en anglais seulement)
The Bavanat Cu-Zn-Ag Besshi-type volcanogenic massive sulfide (VMS) deposit occurs within the Surian volcano-sedimentary complex in the Sanandaj-Sirjan zone (SSZ) of southern Iran. The Surian complex is comprised of pelite, sandstone, calcareous shale, basalt, gabbro sills, and thin-bedded limestone. Mineralization occurs as stratiform sheet-like and tabular orebodies hosted mainly by greenschist metamorphosed feldspathic and quartz feldspathic sandstone, basalt, and pelites. The basalts of the Surian complex show predominantly tholeiitic to transitional affinities, with a few samples that are alkalic in composition. Primitive mantle-normalized trace and rare earth element (REE) patterns of the Surian basalts display depletions in light REE, negative anomalies of Nb, Ta, and Ti, and positive anomalies of P. Positive P anomalies are indicative of minor crustal contamination. Furthermore, Th enrichments in the mid-ocean ridge basalt-normalized patterns of the Surian basalts are characteristic of rifted arc basalts emplaced in continental margin subduction zones. The high MgO content (>6 wt.%) of most Surian basalts and low TiO2 content of two samples (0.53 and 0.62 wt.%) are characteristic of boninites. The aforementioned features of the basalts indicate arc tholeiites emplaced in intra-arc rift environments and continental margin subduction zones. U-Pb dating by laser ablation- inductively coupled plasma mass spectrometry of detrital zircons extracted from the host feldspathic and quartz feldspathic sandstone yields various ages that are predominantly Permian and Triassic; however, the youngest zircons give a mean Early Jurassic concordant U-Pb age of 191 ± 12 Ma. This age, together with geological and petrochemical data, indicate that VMS mineralization formed in the Early Jurassic in pull-apart basins within the SSZ. These basins and the VMS mineralization may be temporally related to an intra-arc volcano-plutonic event associated with Neo-Tethyan oblique subduction.