Description
A special case of freshwater carbonate deposits in man-made settings are calcium carbonate (CaCO3) scale deposits in aqueducts and water conduits of the roman times. They occur across the ancient expansion of the roman empire and therefore in different climate zones, from maritime to continental mid-latitude regions. Such scale deposits can serve as an archive, for the reconstruction of the physico-chemical environmental conditions, the palaeoclimate and the hydrogeology of the catchment and the aquifer. This study therefore aimed to investigate the ancient environmental physico-chemical conditions of the scale deposits of a roman aqueduct channel, the so called „Eifel-Wasserleitung“, that supplied water from the Eifel mountains to the roman city of Cologne, Germany by microstructural and geochemical proxies. In order to reveal the meso- and microstructural fabric as well as geochemical and stable isotope compositions of the CaCO3 scale deposits, petrographic, mineralogical and geochemical analyses have been applied (e.g. light microscopy, XRD, Raman spectroscopy and LA-ICP-MS).First results revealed differences in carbonate mineral nucleation and growth dynamics that are indicated by individual crystal shapes, arrangements and scale textures. The polished hand specimen of the investigated CaCO3 scale deposit shows mesofabric characteristics of individual horizons ranging from 1 to 5 mm in size and low porosity. At the microfabric level, the calcite, which forms the individual laminae, shows different growth types, occurring as microsparit, elongated columnar calcite crystals and thin micritic layers. These growth types are well comparable to other investigations of CaCO3 scale deposits in aqueducts of the roman empire, but they are also frequently found in freshwater carbonate deposits in man-made settings as well as in natural environments, like speleothems. The results of the macro- and microstructural characterization, major/trace element distributions (e.g., Mg, Ca, Sr, Ba) will be discussed in respect to reaction mechanisms and mineral growth rates, potential microorganic influence, and (water) discharge.
| Period | Sept 2023 |
|---|---|
| Event title | MinWien 2023 |
| Event type | Conference |
| Location | Vienna, AustriaShow on map |
| Degree of Recognition | International |
Fields of Expertise
- Advanced Materials Science
- Sustainable Systems