architecture of a distal skarn system: calamita fe-skarn ... removal of low‐solubility components...

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03.05.17 Master ès Sciences in geology Architecture of a distal skarn system: Calamita Fe-skarn deposit, Elba Island, Italy Contact persons: Kalin Kouzmanov (Department of Earth sciences, University of Geneva); Andrea Dini (Institute of Geosciences and Earth Resources, CNR Pisa); [email protected]; Phone +41 (0)22 379 68 93 Context Distal skarns constitute a particular group in the skarn family and their formation away from a causative magmatic body suggests that probably the mineralizing fluids travel over long distances resulting in cooling and selective removal of lowsolubility components prior to skarn formation. Classical hedenbergiteilvaitegarnet distal skarn deposits in Tuscany are systematically associated with, but spatially separated from, the underlying Late MiocenePliocene felsic intrusions. Although mineralogically similar, Tuscan skarns host different ore types (Fe, PbZn, CuZnPb) which genetic relationships with skarnification processes are still debated. Major goal of the project is to characterize the architecture of a distal skarn body at Calamita (Elba Island) as an oreforming environment performing: i) quantitative field study combining a careful threedimensional reconstruction of the skarn body morphology and a precise quantitative analysis of the internal skarn structure, resulting in generation of 2D and 3D maps of the skarn body; ii) textural and quantitative mineral analysis; and iii) trace element characterization of the samples to study the use of major and trace element composition as a vectoring tool. Objectives and Methods The Master project aims to apply a combination of analytical techniques for quantitative mineralogy, textural analysis and geochemical tracing in order to establish detailed paragenesis of both skarn and ore mineralization. Methods to be applied: i) Detailed field mapping and sampling; ii) Transmitted/reflectedlight petrography; iii) QEMSCAN; iv) Cathodoluminescence (SEMCL and coldCL); v) EPMA and LAICPMS. Literature Dünkel I (2002) The genesis of East Elba iron ore deposits and their interrelation with Messinian tectonics. PhD Dissertation, Universität Tübingen. Meinert L, Dipple G, Nicolescu S (2005) World skarn deposits. Economic Geology 100 th anniversary volume: 299– 336. Tanelli G, Benvenuti M, Costagliola P, Dini A, Lattanzi P, Maineri C, Maineri C, Mascaro I, Ruggieri G (2001) The iron mineral deposits of Elba Island: state of the art. Ofioliti 26: 239248. http://cms.unige.ch/sciences/terre/research/Groups /mineral_resources/mineralresources.php http://www.igg.cnr.it/en/organization/iggpersonnel/andreadini/ Choice of orientation : (supprimer les orientations qui ne conviendraient pas) Geochemistry, Alpine tectonics, Ore Deposits

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Page 1: Architecture of a distal skarn system: Calamita Fe-skarn ... removal of low‐solubility components prior to skarn formation. Classical hedenbergite‐ilvaite‐garnet distal skarn

  03.05.17 

Master ès Sciences in geology

Architecture of a distal skarn system: Calamita Fe-skarn deposit, Elba Island, Italy  

Contact persons: Kalin Kouzmanov (Department of Earth sciences, University of Geneva); Andrea Dini (Institute of Geosciences and Earth Resources, CNR Pisa); [email protected]; Phone +41 (0)22 379 68 93 

 

Context Distal  skarns  constitute  a  particular  group  in  the  skarn  family  and  their  formation  away  from  a  causative magmatic body suggests that probably the mineralizing fluids travel over long distances resulting in cooling and selective  removal of  low‐solubility  components prior  to  skarn  formation. Classical hedenbergite‐ilvaite‐garnet distal skarn deposits in Tuscany are systematically associated with, but spatially separated from, the underlying Late Miocene‐Pliocene felsic intrusions. Although mineralogically similar, Tuscan skarns host different ore types (Fe, Pb‐Zn, Cu‐Zn‐Pb) which genetic relationships with skarnification processes are still debated. Major goal of the project is to characterize the architecture of a distal skarn body at Calamita (Elba Island) as an ore‐forming  environment  performing:  i)  quantitative  field  study  combining  a  careful  three‐dimensional reconstruction of the skarn body morphology and a precise quantitative analysis of the internal skarn structure, resulting in generation of 2D and 3D maps of the skarn body; ii) textural and quantitative mineral analysis; and iii) trace element characterization of the samples to study the use of major and trace element composition as a vectoring tool. 

 

Objectives and Methods  The Master project aims  to apply a combination of analytical  techniques  for quantitative mineralogy,  textural analysis and geochemical tracing in order to establish detailed paragenesis of both skarn and ore mineralization. Methods to be applied:  i) Detailed  field mapping and sampling;  ii) Transmitted/reflected‐light petrography;  iii) QEMSCAN; iv) Cathodoluminescence (SEM‐CL and cold‐CL); v) EPMA and LA‐ICP‐MS. 

 

Literature Dünkel I (2002) The genesis of East Elba iron ore deposits and their interrelation with Messinian tectonics. PhD Dissertation, Universität Tübingen. Meinert L, Dipple G, Nicolescu S (2005) World skarn deposits. Economic Geology 100th anniversary volume: 299–336. Tanelli G, Benvenuti M, Costagliola P, Dini A, Lattanzi P, Maineri C, Maineri C, Mascaro I, Ruggieri G (2001) The iron mineral deposits of Elba Island: state of the art. Ofioliti 26: 239‐248.

 

 http://cms.unige.ch/sciences/terre/research/Groups/mineral_resources/mineral‐resources.php  http://www.igg.cnr.it/en/organization/igg‐personnel/andrea‐dini/    

 

Choice of orientation : (supprimer les orientations qui ne conviendraient pas) Geochemistry, Alpine tectonics, Ore Deposits