No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

Das Erzgebirge ist Teilstruktur der Fichtelgebirgs-Erzgebirgischen Antiklinalzone. Es besteht aus einem Gneiskern und einer Schieferhülle, wobei der Gneiskern flächenmäßig den größten Anteil des Erzgebirgskristallins bildet. Die Vorstellungen über den geologischen Aufbau des Erzgebirges haben sich in den letzten 10 Jahren drastisch gewandelt. Moderne PT-Untersuchungen der Gneise und Glimmerschiefer lieferten Beweise einer unterschiedlichen metamorphen Überprägung verschiedener lithologischer Einheiten des Erzgebirges und belegen dessen Deckenbau. Unterschiedliche Altersvorstellungen wurden durch neuere Datierungen erzeugt, da viele Datierungssysteme eine (oft unvollständige) Umstellung durch die metamorphe Überprägung erfuhren. Ziel dieser Arbeit war eine umfassende Charakterisierung der Gneise, die neue Erkenntnisse zu deren Genese und eine gesicherte Altersstellung der Gneise liefert. Die durchgeführten Untersuchungen erlauben die Unterscheidung von drei genetischen Gruppen der Erzgebirgsgneise (Untere "Freiberger" Graugneise, Obere Graugneise, Rotgneise), die unterschiedlichen Altersetappen zugeordnet werden können. Die Unteren Graugneise und die Rotgneise stellen Orthogneise dar ("Meta-Granitoide"), die Oberen Graugneise - Paragneise ("Meta-Grauwacken"). Desweiteren sind sogenannte Mischgneise im Erzgebirge weit verbreitet, die wahrscheinlich aus meta- bis diatektischen Migmatiten hervorgegangen sind. Anhand der Altersdatierungen der Erzgebirgsgneise konnten drei Etappen magmatischer Aktivität belegt werden (ca. 575 Ma, 540-530 Ma, 500-470 Ma), die sehr gut mit magmatischen Zeitmarken anderer saxothuringischer Einheiten (Lausitz, Elbe-Zone, Schwarzburger Sattel) korrelieren. Ein Vergleich der neoproterozoisch-frühpaläozoischen Entwicklung der saxothuringischen Einheiten mit anderen Segmenten des Böhmischen Massivs und des cadomischen Orogengürtels zeigt z.T. auffallende Ähnlichkeiten (insbesondere mit dem Mancellian Terrane des Armorikanischen Massivs) aber auch signifikante Unterschiede auf, die in der Arbeit diskutiert werden.

Peridotites occuring in orogenic massifs provide important insights into geochemical processes of the Earth's upper mantle by providing direct evidence of mantle evolution throughout Earth history. It has been previously demostrated (e.g. Medaris et al., 1990, 2005) that the uppermost tectonic unit of the Bohemian Massif - the Gföhl Nappe hosts a variety of peridotites that originated from different sources, including subcontinental lithosphere, suboceanic asthenosphere, and possible ultramafic layered intrusive complex. The Czech peridotites of the Gföhl Nappe has been divided into three groups, defined by Medaris et al. (1999), according to their chemical compositions, identity and relations of the aluminous phases, ortopyroxen compositions and estimated P-T conditions. According to Medaris et al. (2005) "Type I" peridotites - represented by Mohelno and Biskoupky bodies - equilibrated in low P-T regime (recording the highest equilibration temperatures - up to 1335 ⁰C at 29 kbar - among the Gföhl peridotites) consist of spinel peridotite with garnet appearing only at its margins. Peridotites are enclosed in granulites that have been extensively recrystallized mostly at amphibolite-facies conditions. Many studies have been done on this locality and a wide range of mineralogy and P-T histories has...

Mit dem Grundwasserwiederanstieg in Braunkohleabraumkippen werden die aus der Pyritverwitterung resultierenden Stoffausträge an Sulfat-, Eisen-, Schwermetall- und H+-Ionen gelöst. Im Rahmen dieser Dissertation wurde eine Methodik entwickelt, mit deren Hilfe Problembereiche ausgehalten und somit Maßnahmen im aktiven mitteldeutschen Tagebaubetrieb ergriffen werden können, um die zukünftige Beeinflussung der umgebenden Grund- und Oberflächenwasserkörper zu minimieren. An Vorfeldsedimenten konnten in Feld-eluaten, Stoßbeprobungen und Verwitterungsversuchen geochemische Eigenschaften ermittelt werden. In resultierenden Pufferungsversuchen aus karbonathaltigen Geschiebe-mergeln und Hauptaciditätsträgern konnte eine langfristige Minderung der Aciditätswirkung nachgewiesen werden und ein adaptierter Regelkippenaufbau mit laminaren, alterierenden Sichtaufbau begründet werden. In umliegenden Altkippengrundwässern sind Pufferung und Sulfatreduktion als Wiederfestlegungsprozesse der AMD-Problemstoffe belegt worden. / For lignite mining extensive overburden masses have to be moved. Due to the ventilation of the overburden by atmospheric oxygen, there is a weathering of mostly tertiary sulfides. The rebound of groundwater in future tippings dissolves sulfate, iron, heavy metal and H+ ions, resulting from the pyrite weathering. The partial mobilization of overburden sulfides are opposed to hydrogeochemical buffer reactions e.g. the buffering by carbonates as the first step of buffering. Therefore, there are the questions to the mining operators of the measures that can be taken to minimize the geochemical influence of the surrounding ground and surface water bodies. Object of this PhD-thesis is to lead a methodology that helps to characterize the future tilting substrates to find technological and strategic measures for minimizing the acid water formation in the active open pit operation. In Field eluates and weathering tests in the laboratory and in the field, sediments from dry drill holes in the forefront of open pits “Schleenhain” and “Peres” it could be shown that the geological facies formation of sediments has a decisive influence on geochemical characteristics. As the main acidifying sediment the tertiary aquifer number 2 (lying part) and number 3 can be identified with their high sulfur contents. With increasing time of oxygen exposure sulfate, iron, heavy metal and H + ions released massively. Furthermore, it appears that carbonate buffer essentially are available as glacial till only in cohesive Quaternary. With the resulting buffering experiments from glacial till and the most acidic aquifer sediments a long-term retention of iron, heavy metal and H + - ion and a reduction of sulfate release can be shown, if there is a share of at least 40% glacial till to the lying aquifer number 2 sediments or 20% glacial till to the aquifer number 3. The groundwater quality monitoring of unstructured resaturated old dumps near to the active open pits is comparable to a field test. In addition to weathering zones with high levels of pollutants in the presence of carbonates, buffering processes and sulfate reduction with precipitation of problematic substances in secondary mineral phases can be detected. Blending the research results of geological and geochemical data, an important, in principle selectively recoverable, buffer potential already exists. The determined mixing ratio from 80-60 mass-% acidic sediments to 20-40 mass-% buffering sediment from the buffering experiments can be realized in tilting. In the open pit “Schleenhain” the missing buffering material can be compensated by mass offset from the open pit “Peres”. With the use of the already existing equipment, it is possible to establish a laminar, alternately tipping body with good geochemical and geotechnical conditions.

Over thousands of years, the eastern part of the Mediterranean has developed ways to supply and manage its water resources. The most important evidence of this is the water networks that are distributed in the area. Case studies involving a literature review, fieldwork, sample collection and analysis were conducted that focused on two areas in the West Bank: Nablus city and the northern part of Jordan Valley. These locations were chosen because Nablus city and its vicinity have many of Roman tunnels and aqueducts while the Jordan Valley has many watermills. This study aims to examine the changes in water quality over time in various ways; in an attempt to explain environmental degradation, to understand archeological aspects relating to the water management system, and to piece together what sustained the past environmental development. Throughout centuries carbonate deposits have accumulated along the sidewalls of the water system, containing and archiving geochemical and hydraulic information. These carbonate deposits were sampled from the walls of tunnels together with water samples from the tunnel and surrounding springs in the area. In addition, carbonate sinter has accumulated at the outlet of the watermill on the water shaft. This sinter was also sampled along with water samples from the springs and the water in the Wadi in the area. Water and carbonate samples were analyzed. Water analysis included major cations and anions, trace elements, rare earth elements, 18O/16O isotope ratio, and 87Sr/86Sr isotope ratio. Results indicate the presence of different underground water bodies and Sr resources. Furthermore, thin sections were made from the carbonate samples for SEM–EDX analyses and microscopic investigations. The microscope analysis showed that the distribution of minerals precipitated differs within one sample. Likewise, SEM–EDX results show a variation in element distribution along the growth axis. After finishing the analysis of water samples and thin sections, the layers of the carbonate samples were acidified and trace elements and rare earth elements were measured by means of ICP–MS. Then selected layers were prepared for isotope analyses (18O, 13C, and 87Sr/86Sr) and subsequently measured. The carbonate samples were dated using the U–Th method. Rare earth elements and trace elements measurements provide clear evidence that urbanization has an adverse effect on groundwater quality. Different groundwater bodies were identified by means of geochemical analysis. In the same way, the water sources used to feed the ancient water system were also identified. Through petrological and geochemical analysis, the sustainability of the watermill concept could be demonstrated. This study recommends a more controlled regulation of urbanization expansion. It will only be possible to continue living in this region with sufficient amounts of groundwater and innovative techniques for water supply and management that are environmentally sustainable, as it used to be centuries ago.