Anomalie-Atlas Grundlagen - Screening und Attributierung der bundesweiten Bach- und Flusssedimentgeochemie (Geochemischer Atlas)
The aim of the project is to create the basis for the identification, attribution and cataloging of anomalies in the existing geodata inventory of the nationwide stream and river sediment geochemistry ("Geochemischer Atlas" of Geosphere Austria). The creation and cataloging of anomaly geodatasets is intended to serve as assistance for future research projects to search for deposits of mineral raw materials in the sense of a “Mineral Systems Concept”.
The project aims to create a basis for the identification, attribution and cataloguing of anomalies in the existing geodata set of the nationwide streamsediment geochemistry ("Geochemischer Atlas" of Geosphere Austria) using Geographic Information Systems (GIS).
The analysis of geochemical data (major and trace element contents) represents an essential component in the catalog of methods for the search for mineral deposits. For the analysis of geochemical data, methods ranging from classical statistics, multivariate statistics, and geostatistics to fractal/multifractal models and machine learning algorithms are described in the literature. For some time now, the analysis of geochemical data has been conscious of the fact that, as compositional data (data on compositions, e.g., values in percent or mg/kg - ppm), these data are subject to the so-called "closure problem." For geochemical data obtained from the analysis of sediments in surface water channels, additional methods are often used to consider the associated hydrological catchment areas. The creation of a basis for the creation and cataloguing of an anomaly geodata set from the evaluation of the geodata set of the main and trace element contents of the sediment fraction < 180 µm, for sub-areas also < 40 µm, with a focus on ore deposits (and subordinate industrial minerals), is intended to serve as an aid for future research projects to search for deposits of mineral raw materials in the sense of a "Mineral Systems Concept".
The project work will begin with a search and evaluation of existing literature on prospecting methods using geochemical analyses of streamsediments, as well as on univariate and multivariate statistical analyses of the nationwide streamsediment geochemistry database. In addition, the spatial data sets of the Geochemical Atlas, the Interactive Raw Materials Information System IRIS-Online, and the mining districts of the mining/waste dump cadastre, as well as the morphological catchment boundaries, will be provided and prepared.
For the spatial data set of the Geochemical Atlas (sediment sampling points), the corresponding morphological catchment areas of the surface waters will be computer-assisted selected. Within these catchment areas, the presence and distance to the contents of the Interactive Raw Materials Information System IRIS-Online and the mining districts cadastre are automatically evaluated using GIS, and the data set of the Geochemical Atlas is attributed to the evaluation results. This allows for a cataloging of which references exist to which IRIS deposits and deposits, or to which mining districts and morphological catchment areas.