Category Archives: 2017

The recycling of chromitites in ophiolites from southwestern North America Abstract Podiform chromitites occur in mantle peridotites of the Late Triassic Puerto Nuevo Ophiolite, Baja California Sur State, Mexico. These are high-Cr chromitites [Cr# (Cr/Cr + Al atomic ratio = 0.61–0.69)] that contain a range of minor- and trace-elements and show whole-rock enrichment in IPGE…

Discovery of Ni-smectite-rich saprolite at Loma Ortega, Falcondo mining district (Dominican Republic): geochemistry and mineralogy of an unusual case of “hybrid hydrous Mg silicate – clay silicate” type Ni-laterite Abstract Hydrous Mg silicate-type Ni-laterite deposits, like those in the Falcondo district, Dominican Republic, are dominated by Ni-enriched serpentine and garnierite. Recently, abundant Ni-smectite in the…

Reactive transport model of the formation of oxide-type Ni-laterite profiles (Punta Gorda, Moa Bay, Cuba) Abstract Oxide-type Ni-laterite deposits are characterized by a dominant limonite zone with goethite as the economically most important Ni ore mineral and a thin zone of hydrous Mg silicate-rich saprolite beneath the magnesium discontinuity. Fe, less soluble, is mainly retained…

The recycling of chromitites in ophiolites from southwestern North America Podiform chromitites occur in mantle peridotites of the Late Triassic Puerto Nuevo Ophiolite, Baja California Sur State, Mexico. These are high-Cr chromitites [Cr# (Cr/Cr + Al atomic ratio = 0.61–0.69] that contain a range of minor- and trace-elements and show whole-rock enrichment in IPGE (Os, Ir, Ru). These features…

Towards a unified genetic model for the Au-Ag-Cu Pueblo Viejo district, central Dominican Republic Abstract The origin of the world-class Pueblo Viejo deposit, central Dominican Republic, remains controversial. In this article we scale up the area of study to the Cabirma del Cerro mining concession, which abuts the Pueblo Viejo mining area, and integrate new…

Geological, geochemical and mineralogical characteristics of REE-bearing Las Mercedes bauxite deposit, Dominican Republic Abstract Bauxite deposits, traditionally the main source of aluminum, have been recently targeted for their remarkable contents in rare earth elements (REE). With ƩREE (lanthanoids + Sc + Y) concentrations systematically higher than ~ 1400 ppm (av. = 1530 ppm), the Las…

Trace-element geochemistry of transform-fault serpentinite in high-pressure subduction mélanges (eastern Cuba): implications for subduction initiation Abstract The Sierra del Convento and La Corea mélanges (eastern Cuba) are vestiges of a Cretaceous subduction channel in the Caribbean realm. Both mélanges contain blocks of oceanic crust and serpentinite subducted to high pressure within a serpentinite matrix. The…

Re-Os and U-Pb Geochronology of the Doña Amanda and Cerro Kiosko Deposits, Bayaguana District, Dominican Republic: Looking Down for the Porphyry Cu-Mo Roots of the Pueblo Viejo-Type Mineralization in the Island-Arc Tholeiitic Series of the Caribbean Abstract Hosted in the Early Cretaceous bimodal tholeiite volcanic series of the Los Ranchos Formation, the Doña Amanda and…

Petrogenesis of meta-volcanic rocks from the Maimón Formation (Dominican Republic): Geochemical record of the nascent Greater Antilles paleo-arc Abstract Metamorphosed basalts, basaltic andesites, andesites and plagiorhyolites of the Early Cretaceous, probably pre-Albian, Maimón Formation, located in the Cordillera Central of the Dominican Republic, are some of the earliest products of the Greater Antilles arc magmatism.…

The accumulation of Ni in serpentines and garnierites from the Falcondo Ni-laterite deposit (Dominican Republic) elucidated by means of μXAS Abstract Ni-bearing serpentines and garnierites (Ni-bearing Mg-phyllosilicates) are the main Ni ores in the Falcondo Ni-laterite deposit (Dominican Republic). In the present paper a set of garnierite samples and the associated Ni-bearing serpentines with characteristic…