Tracing the origin of marbles by inclusion fluid chemistry

• Walter Prochaska ^[1] ; Donato Attanasio ^[2]
  1. [1] University of Leoben

     University of Leoben

     Leoben, Austria

     
  2. [2] Institute of Structure of Matter

     Institute of Structure of Matter

     Roma Capitale, Italia

     
• Localización: Interdisciplinary studies on ancient stone: proceedings of the IX Association for the Study of Marbles and Other Stones in Antiquity (ASMOSIA) Conference (Tarragona 2009) / coord. por Anna Gutiérrez García-Moreno, María Pilar Lapuente Mercadal, Isabel Rodà de Llanza, 2012, ISBN 978-84-939033-8-1, págs. 230-237
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Different analytical methods have been applied in the past to pinpoint the origin of marbles, however they often do not discriminate in sufficient detail between marbles of different provenance. Therefore a technique for characterizing marbles was developed which can be used in concert with the established methods. The proposed method is based on the "crush and leach" analysis of extractable total dissolved solids TDS- from marbles and carbonate rocks in general. Samples available from sculptures etc. are very limited in size. Therefore heterogeneity is one of the main problems of conventional provenance detection methods, using the chemical or isotopic composition of marbles to identify their origin. The results from fluid inclusion investigations of carbonate rocks show that the fluid phase is usually relatively uniform with respect to its chemical composition. Metamorphism is an isochemical process and does not homogenize the chemical differences of the protolith (carbonate sediments in the case of marbles). The method presented here is based on the analysis of the chemistry of inclusion fluids which in general were very well homogenized during metamorphic recrystallization. The composition of the extracted solutes depends on the depositional environment of the original carbonate rock (seawater, evaporation brines, primary dolomitization effects, etc.) and on the post-depositional alteration of the inclusion fluids in the marbles. A challenging problem in the field of investigating the provenance of marbles is the discrimination between the s-called Paros II marbles and those from the Marmara island (Prokonnesos marble). Until now these two types of white, medium-grained marbles defied all attempts of discrimination when using the established methods because of their similar isotopic and chemical characteristics. By using the parameters obtained by the chemical analysis of the inclusion fluids a complete separation of the compositional fields and a perfect discrimination between these two marble sites can be achieved