Pablo Rodrigo Leal y Paula Mateo
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Rev. Asoc. Geol. Argent. vol.72 no.2 Buenos Aires jun. 2015
En este trabajo se estudió la mineralización de sulfatos de Ba presente en el anticlinal de Chorriaca. El mapeo de las distintas labores evidenció un fuerte control estratigráfico puesto que todos los depósitos se hallan hospedados en el miembro Agua de la Mula (Formación Agrio). La mineralogía se compone principalmente de baritina, calcita y óxidos de hierro. Los análisis texturales permitieron reconocer tres pulsos de mineralización, de los cuales el último habría sido el más importante. En cristales de baritina de este último se realizaron los estudios de inclusiones fluidas. Las inclusiones primarias más representativas se componen de agua con sales disueltas entre las cuales destacan algunas con cantidades subordinadas de hidrocarburos. Los resultados microtermométricos permitieron definir temperaturas de homogeneización superiores a los 300 °C y soluciones con bajas salinidades. Sobre la base de los resultados obtenidos se postula un origen hidrotermal para las manifestaciones del área estudiada.
Assemblages and microthermometry of barite ore deposits from Chorriaca anticline, Neuquén Province
In this contribution, the barium sulfate mineralization from Chorriaca anticline was studied. All mines are hosted in carbonate layers (Agua de la Mula stratigraphical unit, Agrio Formation) that evidence a strong lithological control. The assemblages is mainly composed of barite, calcite and iron oxides. Their textures imply three mineralization events, from which the last one was the most important. Fluid inclusion studies on barite crystallized during this last event were carried out. The most representative primary fluid inclusions are composed of water with dissolved salts. Few of them also present hydrocarbons on the liquid phases. Microthermometry evidenced homogeneization temperatures above 300°C and solutions with low salinities. Regarding the reasons stated above we propose that this barite mineralization was generated by hydrothermal processes related to the magmatic activity of Neuquén basin.
In this contribution, the barium sulfate mineralization from Chorriaca anticline was studied. All mines are hosted in carbonate layers (Agua de la Mula stratigraphical unit, Agrio Formation) that evidence a strong lithological control. The assemblages is mainly composed of barite, calcite and iron oxides. Their textures imply three mineralization events, from which the last one was the most important. Fluid inclusion studies on barite crystallized during this last event were carried out. The most representative primary fluid inclusions are composed of water with dissolved salts. Few of them also present hydrocarbons on the liquid phases. Microthermometry evidenced homogeneization temperatures above 300°C and solutions with low salinities. Regarding the reasons stated above we propose that this barite mineralization was generated by hydrothermal processes related to the magmatic activity of Neuquén basin.
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