ALBERT

Description: Abstract

Description: This data publication presents data from a solaroptical spectral investigation in the area of the Rammelsberg non-ferrous metal mine in the Harz Mountains near the city of Goslar. The investigation refers to the local communion stone quarry (“Kommunionssteinbruch”) above the former mining area. As this is a nature conservation zone, all measurements were carried out in-situ without any physical sampling action. The field measurements were carried out in June 2019 in cooperation with Bergbau Goslar GmbH and the German Research Centre for Geosciences (GFZ). The data were collected within the research project ReMon (Remote Monitoring of Tailings Using Satellites and Drones, https://www.gfz-potsdam.de/en/section/remote-sensing-and-geoinformatics/projects/remon/) which aims at developing a prototypical monitoring system for mine tailings by using different sensors scaling from satellite- to drone-based. The data were analysed in the unpublished B.Sc. thesis of Constantin Hildebrand (Hildebrand, 2019). Sixteen different surface materials were determined and examined on-site. Point and imaging hyperspectral data were acquired (with the spectroradiometer PSR+ 3500 operating in the range of 350 - 2500 nm and with the Cubert FireflEYEUHD-185 hyperspectral camera with a range of 450 - 950 nm, respectively), both data sets are presented as spectral libraries. Chemical analyses of the samples were performed by using Laser-Induced Breakdown Spectroscopy (LIBS). LIBS data were collected using a handheld LIBS analyzer, the SciAps Z-300. In this data publication the different in-situ measurements are presented for each of the sixteen samples. Detailed information about the analysed material, the area of spectral sampling and geochemical analyses are explained in this report and can also be found in the additional Excel® sheet provided with the data.

Description: Global growth of industry and population leads to increasing demand of industrial and consumer goods. This necessitates an increase in mining activities and resource extraction. Resulting mine waste, and tailings serve as a repository for unused overburden and for the accumulation of processed waste-products. It is typical for so-called secondary iron minerals (SIMs) to be formed during the weathering of these materials under different pH-value conditions. Acid mine drainage (AMD) can result from rainwater infiltration and chemical processes within the deposited mass. Therefore, mine tailings must be spatially separated from their surroundings and monitored. The emergence of remote sensing methods provides new opportunities to survey large areas. In this work a remote sensing approach was used to discriminate SIMs from surrounding material and minerals and subsequently classify different SIMs on the surface. This allows to reconstruct (/comprehend the former) the acidic environments that prevailed during the formation of these minerals and gives indication of the occurrence of AMD. Various SIMs have pH-values ranging from strongly acidic (〈1.5, i.e., Schwertmannite and Copiapite) to neutral (〉7, i.e., Hematite). Classifying these SIMs, leads to the identification of contaminated areas. This method was developed based on a laboratory dataset with different minerals and vegetation samples. The datasets were originally acquired with hyperspectral HySpex cameras in the laboratory and were resampled to WorldView-3 (WV3) and Sentinel-2 (S2) band characteristics for analysis. A combination of different filter methods made pixel-based separation of SIMs possible. The results were subsequently classified using a RF-model to distinguish between different SIMs. In this training dataset, the RF model achieved an overall accuracy of 94.44% for the WV3 and S2 datasets (the area-adjusted overall accuracy was 93.45% and 93.62%, respectively). Subsequently, a second laboratory dataset with field samples was analysed using the same technique and the classification results were compared with XRD analyses of the samples. Satellite images from WV3 and S2 sensors were then analysed using this methodology. The results for the study area of volcanogenic massive sulphide deposits in the Republic of Cyprus, namely Skouriotissa and Apliki, were then compared. The results for the Skouriotissa mine region showed a potential area of 17.22 to 45.58 ha of strongly acidic environment (by classification of Jarosite, pH~2.4) and 8.86 to 26 ha of moderately acidic environment/ contamination (by classification of Goethite/Limonite, pH~5) based on the WV3 satellite image. 27.32 to 87.04 ha and 6.12 to 38.24 ha for the S2 image, respectively.

Description: Das Wachstum von Industrie und Bevölkerungszahl weltweit sowie technologische Fortschritte und Entwicklungen führen zu einer steigenden Nachfrage von Industrie- und Konsumgütern. Als Folge entstehen eine erhöhte Rohstoffnachfrage und ein Ausbau der Ressourcengewinnung sowie des Bergbaus. Abfallprodukte des Bergbaus und nicht genutztes Material (Abraum) werden meist in oder um den Abbaustandort aufgeschüttet. Diese sind natürlichen Degradationsprozessen ausgesetzt, bei denen saure Abwässer entstehen können. Dies geschieht durch die Verwitterung des Pyrit Minerals infolge der Infiltration von Regenwasser durch das Material. In unterschiedlichen pH-Wertumgebungen bilden sich unterschiedliche Minerale aus. Typisch sind die sogenannten sekundären Eisenminerale (SIMs – secondary iron minerals). Ein Auftreten dieser kann daher zu einer pH-Wert Abschätzung genutzt werden und mögliche saure Grubenwässer aufzeigen. Fernerkundungsmethoden bieten die Möglichkeit große Areale oberflächlich zu erfassen und abzubilden, was zu einer weitreichenden Überwachung genutzt werden kann. In dieser Arbeit wurde eine Methode auf Grundlage von multispektralen Fernerkundungsdaten (Satellitenbilder von WorldView-3 und Sentinel-2) entwickelt, welche sekundäre Eisenminerale identifiziert und klassifiziert. Die Identifikation wurde durch den Einsatz von Masken erreicht. So fand eine Unterscheidung zwischen Pixeln statt, die und die keine typische spektrale Signale von SIMs aufweisen. Die Klassifikation wurde mit Hilfe eines RF-Modells durchgeführt. Dieses wurde anhand synthetischer Labordatensätze entwickelt und validiert. Im Trainingsdatensatz erreichte das RF-Modell eine Gesamtgenauigkeit von 94,44 % für die WorldView-3 und Sentinel-2 Datensätze. Es wurden drei Klassen mit verschiedenen pH-Wert-Identifikationen unterschieden: Hämatit (pH〉7), Goethit/ Limonit (pH~5) und Jarosit (pH~2.4). Die Methodik wurde anschließend auf Satellitenbilder aus der Republik Zypern angewendet. Dabei standen die Minengebiete Skouriotissa und Apliki im Fokus, welche zu den vulkanogenen Massivsulfid-Lagerstätten (VMS-type) zählen. Die Ergebnisse für das Skouriotissa-Minengebiet ergaben auf der Grundlage des WV3-Satellitenbildes eine potenzielle Fläche von 17,22 bis 45,58 ha in stark saurem Milieu (Jarosit) und 8,86 bis 26 ha in mäßig saurem Milieu (Goethit/ Limonit) bzw. 27,32 bis 87,04 ha und 6,12 bis 38,24 ha für das Sentinel-2 Satellitenbild.

Description: This Technical Report presents data from a solaroptical spectral investigation in the area of the Rammelsberg non-ferrous metal mine in the Harz Mountains near the city of Goslar. The investigation refers to the local communion stone quarry (“Kommunionssteinbruch”) above the former mining area. As this is a nature conservation zone, all measurements were carried out in-situ without any physical sampling action. The field measurements were carried out in June 2019 in cooperation with Bergbau Goslar GmbH and the German Research Centre for Geosciences (GFZ). The data were collected within the research project ReMon (Remote Monitoring of Tailings Using Satellites and Drones, https://www.gfzpotsdam. de/en/section/remote-sensing-and-geoinformatics/projects/remon/) which aims at developing a prototypical monitoring system for mine tailings by using different sensors scaling from satellite- to drone-based. The data were analysed in the unpublished B.Sc. thesis of Constantin Hildebrand (Hildebrand, 2019). Sixteen different surface materials were determined and examined on-site. Point and imaging hyperspectral data were acquired (with the spectroradiometer PSR+ 3500 operating in the range of 350 - 2500 nm and with the Cubert FireflEYEUHD-185 hyperspectral camera with a range of 450 - 950 nm, respectively), both data sets are presented as spectral libraries. Chemical analyses of the samples were performed by using Laser-Induced Breakdown Spectroscopy (LIBS). LIBS data were collected using a handheld LIBS analyzer, the SciAps Z-300. In this report the different in-situ measurements are presented for each of the sixteen samples. Detailed information about the analysed material, the area of spectral sampling and geochemical analyses are explained in this report and can also be found in the additional Excel® sheet provided with the data.

Description: Die Bundesrepublik Deutschland hat sich zum Ziel gesetzt, bis 2045 klimaneutral zu werden. Das kann nur funktionieren, wenn fossile Rohstoffe durch erneuerbare Energien ersetzt werden - insbesondere in den Bereichen Industrie und Verkehr. Ein wesentlicher Baustein in diesem Transformationsprozess ist die Errichtung einer Wasserstoffwirtschaft, innerhalb derer Strom aus erneuerbaren Energien in grünen Wasserstoff umgewandelt und dieser als Energieträger vor allem in den Bereichen Industrie und Verkehr angewendet wird.