@article{fdi:010072337,
  title = {{T}he {M}arbat metamorphic core-complex ({S}outhern {A}rabian {P}eninsula) : reassessment of the evolution of a {N}eoproterozoic island-arc from petrological, geochemical and {U}-{P}b zircon data},
  author = {{B}arbey, {P}. and {D}enele, {Y}. and {P}aquette, {J}. {L}. and {B}erger, {J}. and {G}anne, {J}{\'e}r{\^o}me and {R}oques, {D}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {M}arbat basement ({S}ultanate of {O}man) belongs to the {N}eoproterozoic accretion domain of the {A}rabian-{N}ubian shield. {W}e present new geochronological, petrological and geochemical data as an extension of our previous study ({D}enele et al., 2017) re-interpreting this basement as a metamorphic core complex ({MCC}). {W}e showed that this {MCC} consists of a metamorphic unit ({J}uffa complex) separated by an extensional detachment from a plutonic unit ({S}adh complex and {T}onalite plutons). {G}eochemical data show that the {J}uffa metasediments correspond to volcanogenic graywackes, suggesting deposition in front of a juvenile magmatic arc. {N}ew in situ {U}-{P}b zircon data show that the protolith of the {J}uffa paragneisses is {T}onian in age (960-830 {M}a). {T}he {J}uffa complex recrystallized under amphibolite facies conditions (950 {MP}a, 630 degrees {C}) corresponding to thermal gradient of 17-18 degrees {C}/km, i.e. close to that observed in fore-arc environment subjected to tectonic underplating. {I}t was then retrogressed (< 400 {MP}a, < 400 degrees {C}) during exhumation of the {MCC}. {P}hase assemblages of the {S}adh complex and {T}onalite plutons record magmatic temperatures estimated at 700-840 degrees {C} and 610-840 degrees {C} from hornblende and zircon-saturation thermometry, respectively; pressures are grossly estimated at ca. 250 {MP}a. {T}hese data and structural evidence led us to consider that the {S}adh complex is a plutonic unit emplaced during exhumation of the {MCC}. {H}ence, we re-interpret the previously published zircon core {U}-{P}b ages of the {B}anded gneisses (ca. 860-830 {M}a) as inherited, and zircon rim ages (ca. 815 {M}a) as the age of their intrusion. {T}his suggests that the parent magma of all these granitoids could have interacted with volcanic material equivalent to the {J}uffa complex. {O}verall, the {M}arbat area developed during the {T}onian and involved (i) deposition of volcanosediments ({J}uffa complex) in an island-arc environment (960-830 {M}a); (ii) metamorphism under middle pressure conditions during tectonic underplating at ca. 820-815 {M}a, followed by emplacement of plutonic rocks in the upper crust during initiation of the {MCC} at ca. 815-810 {M}a; and (iii) late-tectonic intrusions associated with {MCC} amplification at ca. 800-790 {M}a ({M}ahall intrusives and {T}onalite plutons).},
  keywords = {{N}eoproterozoic ; {A}rabian-{N}ubian shield ; {O}man ; {M}etamorphic core complex ; {Z}ircon {U}-{P}b ; {T}ectonic underplating ; {OMAN} ; {ARABIQUE} {PENINSULE}},
  booktitle = {},
  journal = {{P}recambrian {R}esearch},
  volume = {305},
  numero = {},
  pages = {91--110},
  ISSN = {0301-9268},
  year = {2018},
  DOI = {10.1016/j.precamres.2017.12.013},
  URL = {https://www.documentation.ird.fr/hor/fdi:010072337},
}