Seminare und Treffen

Seminare und Treffen mit Vorträgen und Besprechungen der Abteilungsthemen. Die Termine finden immer wochenweise abwechselnd statt:
Seminar and Get-together to discuss department issues and topics. Every second monday alternating, see schedule:

14. Nov. 2022, 13:00 Uhr / 1pm
David Peacock - A comparison between structural styles interpreted in the Variscan Orogenic Belt

Kurzfassung / Abstract:
Structural cross-sections have been constructed in the Variscan Orogenic Belt in both the Harz Mountains (central Germany) and the Rhenish Massif (western Germany, eastern Belgium, Luxembourg and NE France) as part of a project on the geothermal potential of these regions. Cross-sections in the Harz Mountains were constructed using Move software, and were based on geological maps and lithological data from several wells. These cross-sections show Variscan folds cut by later normal and/or strike-slip faults. Cross-sections in the Rhenish Massif were constructed using forward modelling software, and were based on both geological maps and a detailed lithostratigraphic and structural analysis of a well at Havelange, Belgium. These cross-sections show a classic thin-skinned thrust belt, in which folds are related to the ramp-flat geometries of thrusts. The cross-sections for the two regions therefore show significant differences because of the data and section construction methods used, and possibly also because of the backgrounds of the researchers. Well-exposed coastal cliff exposures in Cornwall and Pembrokeshire (UK) show fold-thrust structures that indicate the Variscan Orogenic Belt tends to have structures that are intermediate between the cross-sections for the Harz Mountains and the Rhenish Massif.


21. Nov. 2022, 13:00 Uhr / 1pm
Abteilungstreffen / Department meeting
Thema: Lehre / Topic: Teaching


28. Nov. 2022, 13:00 Uhr / 1pm
David Hindle - Central Western European tectonic revolution


05. Dec.. 2022, 13:00 Uhr / 1pm
Abteilungstreffen / Department meeting


12. Dec. 2022, 13:00 Uhr / 1pm
Mukhtiar Ghani - Tectono-stratigraphic evolution of Western Indian plate boundary region, Balochistan, Pakistan

Kurzfassung / Abstract:
The western plate boundary of Indian plate is different from northern collisional in terms of stratigraphy and tectonic. In this talk, I will discuss the stratigraphic architecture of different tectonic basin in the collisional zones and possible impact of tectonic and large scale structures on the development of these basins. The cotemporaneous evolution, basement configuration and already developed structural model will be presented in details.


15. December 2022, 11:30 - 23:00 Uhr / 11.30 am to 11.00 pm

Weihnachtsausflug / Christmas event:

"UNESCO-Welterbe Oberharzer Wasserwirtschaft" und Lehrbergwerk in St. Andreasberg/Harz (1 Tag)
Exkursionsleiter Dr. Bernd Leiss, Geowissenschaftliches Zentrum der Universität Göttingen

- 11.30 Abfahrt GZG
gegen 13.00 Uhr: Einführung in Obertageanlagen Oderteich und Rehberger Graben sowie in situ Wollsackverwitterung des Brockengranits (Bernd Leiss)
- 14.00 (fixer Zeitpunkt): Einfahrt in die Grube Samson in St. Andreasberg mit Sonderführung der Bergwerksleitung incl. Konzepte erneuerbarer Energien (Koordination Lasafam Iturrizaga)
- 16.00: Einfahrt in Lehrbergwerk "Wenns glückt (Roter Bär)", kein Schaubergwerk, sondern historisches Bergwerk im Orignalzustand, Ausrüstung und Kleidung wird gestellt, nur Grubenlampen und unebene Wege (Führung Wilfried Ließmann, der Harzer Montanhistoriker schlechthin)
- gegen 19.00 gemütliche Einkehr zum Weihnachtsessen
- Rückkehr gegen 23.00 Uhr

Individuelle Anfahrt möglich. Anmeldungen bitte an Marie-France Hesse (mhesse1@gwdg.de, Tel.: 0551-39-27931)


09. Jan. 2023, 13:00 Uhr / 1pm
Hernán Silva Lara - Reassessing the polyphase Neoproterozoic evolution of the Punta del Este Terrane, Dom Feliciano Belt, Uruguay

Kurzfassung / Abstract:
Some recent models challenge the position and extension of the assumed oceanic basins formed through the break-up of Rodinia, and the tectonic processes involved in the Gondwana assembly, making the investigation of the Early Neoproterozoic record of great relevance. Within the South-American Atlantic margin, the Punta del Este Terrane (PET) of the Dom Feliciano Belt (DFB) comprises a unique Tonian to Ediacaran record, and has a strategic position to reconstruct spatio-temporal relationships with the southern African orogenic belts. Novel zircon U–Pb and Lu–Hf data from the PET basement orthogneisses display Tonian magmatic ages (805–760 Ma) and Hf isotopic signatures indicative of mainly crustal/metasedimentary sources, (Nd TDM ages: 2.2–1.9 Ga, and εHf(t): − 12 to − 4). The basement paragneisses yielded late Paleoproterozoic to Neoproterozoic U–Pb ages, but dominantly positive εHf(t) values. The presented results confirm the correlation of the PET with the Coastal Terrane of the Kaoko Belt, and discard the idea of the Nico Pérez Terrane as a source. Detrital zircon U–Pb and Lu–Hf data from the Rocha Formation yielded a main peak at ca. 660 Ma, with the Neoproterozoic grains showing a εHf(t) between + 1 and + 14. The deposition age of the Rocha Formation is constrained by the youngest detrital zircon age peak (660 Ma), and the beginning of the deposition of the Sierra de Aguirre Formation (580 Ma). The data indicate common sources with the Marmora Terrane, and it is thus proposed that the Rocha Formation belongs to the Gariep Belt, and it was juxtaposed during the Ediacaran to the DFB.


16. Jan. 2023, 13:00 Uhr / 1pm
Abteilungstreffen / Department meeting
Themen: Lehre und Abteilungsverwaltung / Topics: Teaching and department administration


23. Jan. 2023, 13:00 Uhr / 1pm
Fiorella Arduin Rode - Uruguayan amethyst and agate deposits: field, fluid inclusions and stable isotope

Kurzfassung / Abstract:
Amethyst and agate geodes hosted in basalt of the Paraná-Etendeka Igneous Province comprise the only world class deposit of Uruguay being an important export product of the county. However, the forming conditions and the estimation of remaining reserves are still matters of discussion. The origin of the mineralizing fluid has been subject to different proposals, with models involving magmatic, post-magmatic/epigenetic processes, or host rock - surface water/groundwater interactions. In order to give new insights to this problem, field observations in combination with fluid inclusions studies and stable isotope analyses were carried out in the mineralized lava flows of the Los Catalanes mining district. Three stages can be distinguished in the geode fillings: the first stage include celadonite, zeolite, chalcedony, calcite, micro-crystalline quartz, pyrite and chalcopyrite, the second macro-crystalline colourless quartz and amethyst, and the third stage late calcite, sporadic fluorite and pyrite. Primary and pseudo-secondary fluid inclusions in amethyst, colourless quartz and calcite contain predominantly monophase liquid. Since spontaneous nucleation of the vapour bubble fails to occur in these inclusions, single ultra-short laser pulses were applied to stimulate bubble nucleation in the metastable liquid. This allowed subsequent measurement of homogenization temperatures, which range from 10 to 130 °C in amethyst and colourless quartz, and from 20 to 90 °C in early and late calcite. Ice melting temperatures measured at saturation pressure, i.e., in presence of a vapour bubble, revealed low salt concentrations up to 3.8 wt% NaCl. Oxygen isotopic compositions on silica minerals and carbonates suggest a relatively low temperature environment with crystallisation from a single fluid composition with temperature fluctuations. These data point to low salinity - close to pure water - and low temperature for the fluid responsible in the geode mineralization.


06. Feb. 2023, 13:00 Uhr / 1pm
Abteilungstreffen / Department meeting
Themen: Sicherheitsbelehrung (Schwerpunkt Gelände, neue Kollegen) / Topics: Saftey briefing (Emphasis on Field work, new colleagues)


13. Feb. 2023, 13:00 Uhr / 1pm
Abteilungstreffen / Department meeting


20. Feb. 2023, 13:00 Uhr / 1pm
Mathias Hueck - Titel wird noch bekannt gegeben / Title t.b.a.


06. Mar. 2023, 13:00 Uhr / 1pm
Tim Hahn & Ali Abdelkhalek - Titel wird noch bekannt gegeben / Title t.b.a.