02/12/2016 -03/12/2016 BARCELONA STUDENT CHAPTER’S WORKSHOP: SKARN DEPOSITS

Due to the high rate of participation in the previous activities organized by the Barcelona Student Chapter, we were more than devoted to the organization of our 5th workshop dedicated to skarn deposits, which was held on the 2nd and 3rd of December at the Faculty of Geology of the University of Barcelona. It counted with the total participation of 29 assistants, some of them even coming from the University of Oviedo, Asturias. The aim of this workshop was to provide an approach of these types of deposits regarding: their structure and genesis, their geochemistry, petrology, mineralogy and a review on the diverse techniques used in their exploration to undergraduate, master and PhD students, as well as for other professionals interested in these typology of deposit.

Morning of day 2nd December consisted of a cycle of conferences in which the followings were imparted: Albert Soler Gil (University of Barcelona) opened the session with an introductory lecture entitled Skarn-type deposits: genetic models in the Iberian Hercynian in which members were enlighted with the different complex processes responsible for the formation of these deposits, their structure, petrochemistry and classification. Proceeding into detail, Abigail Jiménez Franco (PhD student from the Polytechnical University of Catalonia- EPSEM) explained a particular example of skarn deposit with her lecture entitled The Velardeña (Zn-Pb-Cu) Skarn: new data on the mineralogy, fluid inclusions and isotopic geochemistry. Finally, Lluís Boixet Martí (Country Manager; Minería de Corcoesto S.L – Edgewater Exploration Ltd) treated the assistants to a memorable lecture entitled Prospection of auriferous deposits in the Iberian Peninsula. An example: the Carlés Skarn, Asturias in which members were provided not only with academic information but also with a business-exploration point of view.

In the same afternoon, assistants were invited to a 3-hour practical session imparted by Albert Soler that included hand-sample observation of numerous skarn samples and the visualization of the ores of these ones under reflected light microscope . During this session, assistants recognized various mineralogical assemblages of different types of skarns and familiarized with those samples belonging to the deposits visited on the fieldtrip.

The Barcelona Student Chapters one-day fieldtrip, leaded by Albert Soler, took place on the 3rd of December. It consisted on the observation and study of a few distal and proximal skarns located in the Axial Pyrenees, closely related to the magmatic intrusions of the late Hercynian orogeny, which included: an idiocrase skarn, a hedenbergite skarn, a pyrrhotite skarn and an arsenopyrite skarnoid (Fig.6). Assistants were deeply involved and had great pleasure in listening to all explanations regarding the processes associated to the genesis of each of these deposits and had the opportunity to acquire exceptional hand samples.

 

We gratefully acknowledge all lecturers: Albert Soler Gil, Abigail Jiménez Franco and Lluís Boixet Martí for their overwhelming speeches. In addition we express our most true gratitude to the SGA for the economic support offered, which allowed us to develop and carry out successfully all our activities as well as to the Faculty of Geology for their logistic and equipment provided.

SGA-SEG WORKSHOP 2016: LOS DEPÓSITOS SKARN

Afegim també el formulari per accedir al workshop sense ser membre explícit de la SGA/SEG

Coffee stand 21st September

 
 
On day 21st of September a coffee stand was organized by the SGA-SEG members in order to welcome the new academic year. The planned activities encompassed the whole morning and afternoon and included diverse talks. The first three presentations corresponded to the final degree project of three graduated members from 2016: 
Mineralogía y Geoquímica del Yacimiento de bauxitas Las Mercedes y otros depósitos de la Sierra de Bahoruco, República Dominicana, by Daniel García, Multidisciplinary mineralogical characterization of PGM from the Loma Caribe peridotite, (Dominican Republic), by Sandra Baurier and Geochemical characterization of Late Neogene tephra layers in the Minas de Hellín and Cenajo Basins (SE Spain), by Anna Mireia Rabaza.
 
 
In addition, few members who attended the collaborative expedition with the Siberian Student Chapter this previous summer 2016 reported their experience in a casual and relaxed way before continuing with the welcoming celebration of the new academic year. 

SGA SIBERIAN FIELD TRIP

During the first weeks of last August 2016 and after intense planning, the Siberian Student Chapter and the Barcelona Student Chapter put a beginning to their collaborative expedition fieldtrip. This consisted on the first collaboration with any other Student Chapters from part of the Barcelona Student Chapter and it could not have gone any better, consisting on a thoroughly planned and amazing week-long fieldtrip throughout Southeastern Siberia composed by seven members of each Chapter. 
 
 
During the first days the students had the opportunity to visit some important ore deposits of Siberia: the Kamenushikoe Cu deposit and the Salairskoe Pb-Zn deposit, located 300km from Novosibirsk in the Salair Ridge (Kemerovo Region), and Sinyuhinskoe Au deposit, located in northeastern Altai. The two types of ore commonly found at Salairskoe Pb-Zn ore field were characterized by massive carbonate-quartz-barite ore and disseminated barite-polymetallic ore whereas in Kamenushikoe Cu deposit ore minerals were represented mainly by pyrite and chalcopyrite. In addition, students had the chance to collect amazing hand samples of azurite, malachite and chrysocolla between others. On the other hand, at Sinyuhinskoe Au deposit, members were provided insights on the skarns of different compositions developed in tuffs and carbonate rocks in the contact zone with the Sinyukha massif, mainly on the wollastonite, garnet-wollastonite and pyroxene-wollastonite skarns associated with sulfide minerals. 
 
 
When interning into the Altai Mountains, the Siberian Student Chapter excellently guided the Barcelona members to both geological and cultural places of interest such as a) the largest natural history museum in Siberia; the “Paleopark”, b) the Cambrian – Ordovician Gornoaltaisk formation “Dragon’s teeth”, c) middle Devonian volcanites related to the continental margin in western Altai-Sayan foldbelt activity, d) a bewildering catastrophic glacial megaflood deposit called Inskoy “stone garden”, e) the beautiful confluence of Chuya and Katun’ rivers and its complex terraces, f)  fossil-bearing Silurian limestones belonging to the Gromatukhinskaya series, g) petroglyphs of Turkic peoples (9000-6000 B.C), h) the Kol’ka Snegiryov Monument and j) the well-known Shirlak waterfall and the alluring blue lake near Aktash Village. 
Above all, we want to thank the SGA Siberian Student Chapter for their dedication, their guidance and for having provided and shared such joyful and memorable moments with us and to the SGA itself for having supported this collaborative expedition from the beginning. 
 

14/05/2016 BARCELONA STUDENT CHAPTER – SANT JULIA DE LLOR I BONMATI MINING DISTRICT FIELD TRIP (MONTSENY-GUILLERIES: GIRONA).

The past fourteenth of May, ten of our students went to a fieldtrip to Sant Julià de Llor i Bonmatí mining district. Located in the, Montseny-Guilleries region, this  district had a great importance in the Spanish mining history, and was active during eighteenth, nineteenth and twentieth centuries (until 1972).
 
The main objective of this fieldtrip was to study the “Puig de Sant Julià” open-pit mine, where F-Ba (Pb-Zn- Cu) mineralisations were extracted. These mineralisations are located in fracture-associated veins, strata-bounded layers and Cambrian to Silurian metasomatic marbles and calc-silicates (Skarns).
 
The minerals that form the host rocks are mainly carbonates, such as calcite and dolomite, but there is also quartz, tremolite-actinolite, diopside and white micas (phlogopite and/or margarite).
 
The minerals forming the ore deposits are mainly sulfides, such as pyrite, chalcopyrite and galena. Malachite, pyrolusite, melanterite and goethite are present, but as a product of sulfide alteration (supergene). Additionally, some barite veins are found cutting the host rock and ore deposits.
 
 

The geochemistry of Ni in lateritic profiles and its relationship with the hosting minerals.

 

The laterite deposits placed in the Caribbean contain a significant amount of Ni.  Despite their geological relevance and economical interest, no detailed studies existed with regards to the mobility of Ni and its incorporation in their hosting minerals along the profiles. In the present talk, a set of results obtained by means of EMPA, µRAMAN, µXRF and µXAS from oxide type laterites from Cuba and silicate type laterites from Dominican Republic are presented. We studied the distribution of Ni in the limonitic and in garnieritic horizons to elucidate how Ni is accumulated in Mn-oxyhidroxides and within the Mg-hydrated phyllosilicates. The obtained results helped to explain the distribution and accumulation of Ni and the development of laterites from Moa-Bay and Falcondo Ni-laterite deposits. These studies also highlight how physicochemical factors such as soil porosity, pH regime and silica activity do have important implications for Ni accumulation and mobility across the profile.

Citing the lecturer, Josep Roqué Rosel himself:

“My research is focused on the measurement of the structure and chemistry of inorganic materials, with the goal of understanding and predicting their properties down to molecular levels. These in turn fundamentally control a wide range of geological and technological phenomena. I work primarily on ordered and disordered materials, including minerals, glassy silicates and ceramics. My primary research tools are X-ray Absorption Spectroscopy (XAS) and Transmission Electron Microscopy (TEM). The materials that I study are natural samples or are synthesized in the laboratory. The problems that I address are tied to large-scale processes in geology and geochemistry, as well as to those in high-tech industries. Among the former are the mechanisms involved in lateritic profile development and the accumulation of metals in soils; among the latter are the study of glasses, the study of the decay by-products in batteries and the optimization of catalysts.”

Vivencias y experiencias de un estudiante de Ingeniería Geológica en República Dominicana: el paso de la universidad a Barrick-Pueblo Viejo

Bye Bye Doctoral Thesis

We are joyful to announce that our first members – the same who founded, started to develop and build our Student Chapter – have finished their doctoral thesis! After enduring years of intense dedication and laborious hard work, which include “the syndrome of PhD stress suffering” and “high peaks of registered enthusiasm and motivation”, Cristina Villanova de Benavent, Thomas Hans Aiglsperger and Marc Campeny Crego have finally completed with excellence their goal and undergone the best way possible this adventure. It’s unbelievable the way time flies: only some years ago these amazing people were on the verge of beginning a doctoral thesis – a complicated and hard path but, when looked back; it leaves you a great feedback of awesome memories, an enormous backpack full of experience and the undeniable feeling that by confronting this challenge you cannot fear working on new ideas and that whatever it may-be-to-come. You will take it and overcome it.

From left to right: Cristina Villanova de Benavent, Thomas Hans Aiglsperger and Marc Campeny Crego. 

Always counting with the support of their advisors; Joaquín Proenza and Salvador Galí (for Cristina Villanova), Joaquín Proenza (for Thomas Aiglsperger) and Joan Carles Melgarejo Draper and José Mangas (for Marc Campeny), our first members, including our first president between them, will defend their work during the following weeks in the Faculty of Geology of the University of Barcelona:

Cristina Villanova de Benavent with "Compositional and structural charaterisation of Ni-phyllosilicates in hydrous silicate type Ni-laterite deposits" on the 11th of December 2015 in the Aula Magna at 11.00 h.

Thomas Hans Aiglsperger with "Mineralogy and geochemistry of the platinum group elements (PGE), rare earth elements (REE) and scandium in nickel laterites" on the 17th of December 2015 in the Aula Magna at 11.00 h.

Marc Campeny Crego with “The carbonatitic volcanism of Catanda, Angola” on the 20th of January 2016 in the Aula Magna at 11.00 h.

2015 Barcelona Student Chapter’s workshop: Ultramafic Ronda & Ojén Massifs: petrology, geochemistry and Cr-Ni-PGE associated mineralizations

Instead of undergoing a workshop consisting of several introductive lectures and a one day fieldtrip the Barcelona Student Chapter’s workshop of 2015 consisted of a two day field-workshop entitled“Ultramafic Ronda & Ojén Massifs: petrology, geochemistry and Cr-Ni-PGE associated mineralizations”.  The whole field-workshop was developed in the two small massifs of Ronda and Ojén (Málaga) during the 11th and 12th of September.

The peridotite massif of the Serranía de Ronda comprise three massifs (Ronda, Ojén and Carratraca) located in the westernmost internal zone of the Betico-Rifean Cordillera, which constitutes the westernmost segment of the Alpine belt in Europe. These massifs are made up primarily of lherzolite and harzburgite with minor dunite and pyroxenite layers. They represent portions of subcontinental lithospheric mantle tectonically emplaced at high temperature and high pressures into Paleozoic metasediments during the 20/22 Ma Alpine orogeny. Peridotites are zoned into three main lithological domains: a) spinel ± garnet tectonic domain, b) granular peridotite domain and c) plagioclase tectonic domain.

A small group of members including undergraduate, master and PhD students was led by Prof. Fernando Gervilla; full professor of the University of Granada and Joaquin Proenza (advisor) during the whole fieldtrip (Fig. 1.). These students had the opportunity to learn from an invited professor who has dedicated years of his research on the study of the Ronda peridotites; and furthermore, recently co-authored “Liquid immiscibility between arsenide and sulfide melts: evidence from a LA-ICP-MS study in magmatic deposits at Serranía de Ronda (Spain)”.

Fig.1. Groupal photograph taken in an outcrop characterised by chromitite and niqueline altered to annabergite mineralisation. Close to this outcrop spinelites mineralisation.

The first day was devoted to a cross-section study of the orogenic lherzolites of the subcontinental mantle which crop out in the Ronda massif. Firstly observed; the garnet peridotites where graphite pseudomorphs after diamond have been described (Crespo et al. 2006). Later on; the spinel peridotite and finally the peridotites with plagioclase.

 

Fig.2; Left image: Local acid diques of granitic composition. Right image: Gallega mine. Observation of chromite and niqueline mineralisations. Some of these veins also containing cordierite. 

 During the second day small chromite and Ni arsenide mines were visited: ex) Gallega Mine (Fig.2) where students had the opportunity to search for interesting hand-samples and acquire the experience of discerning between the diverse mineralogies present.

 

13th SGA Biennial Meeting at Nancy

Finally 12 students comprising undergraduates, master and Phd attended to the 13th SGA Biennial Meeting at Nancy, France, which took place from the 24th to the 27th of this last August. They presentend i) poster or ii) oral research projects and Final Degree Projects (TFG). For some of them this experience was a reminder of other conferences, for others their first time exposing. Either way, everybody concluded that the time spent there was… just wonderful.

The opportunity to meet experts of an specific field and entablish conversations, to attend to the diverse and rich oral presentations given by speakers from all around the world, the chance of presenting your own work and seeing others’, and finally getting to know people from other Student Chapters; all of it consisted in an amazing experience. 

  • Sandra Baurier with “Chromian spinel composition, PGE geochemistry and mineralogy of recently discovered chromitite bodies from the Loma Caribe peridotite, Dominican Republic”

  • Cristina Villanova with “Fe-Ni-rich serpentines in the saprolite horizon of Ni-laterite Carribbean deposits: a new approach from thermodynamic calculations”

  •  Thomas Aiglsperger with “Multistage PGE nugget formation in Ni-Laterites: from hypogene to supergene, new insights from Falcondo (Dominican Republic)”

  • Mariona Tarrago with “Diffusion of heavy metals during vitrification of chromium sludge in a basaltic matrix: model of a melting pond in an alumina crucible”

  • Andreu Cacho with “Huanuni, Bonanza and la Suerte mines: mineralogy, geochemistry and structure”

  • Clara Román Alday with “The Romero Cu-Au-Zn deposits, Cordillera Central, Dominican Republic: Preliminary data on the mineralogy and geochemistry of mineralization”

  • Guillem Sánchez with “Au- and PGE-rich massive sulphide deposits associated with serpentinized peridotites of the Havana-Matanzas Ophiolites, Cuba”

  • Lisard Torró with  “Geochemistry of the VMS bearing Maimón Fm. (Central Cordillera, Dominican Republic): assignation to a fore-arc environment in a nascent intraoceanic island arc”

  • Abigail Jimenez with “Mineralogical characterization of Sn deposits from the Santa Fe district, Bolivia”

 

2015 Closure Event

2015 academics’ year ending consisted in diverse outstanding talks given by both undergraduated and graduated students (Phd). Lisard Torró presented Weathering Profile of The Cerro de Maimón Vms Deposit (Dominican Republic): Textures, Mineralogy, Gossan Evolution and Mobility of Gold and Silver in Pope for an hour session, whilst numerous other students gave a short and intensive 10 minutes talks in english:

Daniel Rodríguez with “Au mineralisation in listvenites from a serpentinisedophiolite complex in Mina Descanso (Central Cuba)”, Mariona Tarragó with “Diffusion of heavy metals during vitrification of chromium sludge in a basaltic matrix: model of a melting pond in an alumina crucible”, Miriam Pastor with “The San José-Itos mines, Oruro, Bolivia: Structure and Ag-Sn Mineralization”, Lisard Torró with  “Geochemistry of the VMS bearing Maimón Fm. (Central Cordillera, Dominican Republic): assignation to a fore-arc environment in a nascent intraoceanic island arc”, Cristina Villanova with “Ni-enrichment processes revealed by TEM imaging on garnierites”, Clara Román Alday with “The Romero Cu-Au-Zn deposits, Cordillera Central, Dominican Republic: Preliminary data on the mineralogy and geochemistry of mineralization”.

These presentations consisted in the exposition of final degree Projects (TFG), final master Projects (TFM) and even other post-master research projects, all of them resulting in succesful talks which enhaced motivation and participation within attendants. After these sessions a coffee stand was displayed and every participant could enjoy the company of our collegues and bid farewell to our friends before entering the forecoming summer. 

     

 

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