Fluid systems and mineralization in the north German and Polish basin

Abstract

The North European Basin hosts mineral deposits like the Kupferschiefer and the Mississippi Valley Type deposits in the Silesian sub-basin in Poland. The basement to this basin, exposed in the Harz Mts and in the Flechtingen and Calvö rde Blocks, contains Mesozoic Pb-Zn vein mineralization and barite-fluorite deposits as well as massive hematite veins in the Rotliegend volcanics. A comparison of the mineralizing models of these deposits with results from a basin-wide petrographic, fluid inclusion and stable isotope study shows that the genesis of the mineral deposits can be explained by fluid systems that were active during different stages of basin evolution. These comprise syn-to post-magmatic fluids derived from or mobilized in the course of the Rotliegend magmatism, fluids convecting in the Rotliegend units during the extensional basin subsidence in the Permo-Triassic and originating from progressive devolatilization of the basin sequence and fluids derived from the overlying Zechstein evaporites. Deep-reaching fault systems developing during the Cretaceous tectonic reactivation enhanced fluid percolation from the surface to the deep sections of the basin sequence. Identification and correlation of these fluids across the basin and in the mineralizations provide the base for a basin-wide metallogenetic model.

Fluid and gas migration in the North German Basin: fluid inclusion and stable isotope constraints

“…quartz I fi carbonate fi quartz II). Multiple fluid migration within the NGB has also been suggested by, for example, Rieken (1988), Rieken and Gaupp (1991), Reutel and Lu¨ders (1998), Lu¨ders et al (1999), Wolfgramm (2002), Schmidt Mumm and Wolfgramm (2004).…”

“…The formation of quartz and/or agate nodules is most probably related to late magmatic fluid migration (Schmidt Mumm and Wolfgramm 2004). Fluid inclusions in quartz from nodules that probably precipitated at a late magmatic stage show highly variable liquid-vapour ratios probably due to variable formation temperatures.…”

REY and Trace Element Chemistry of Fluorite from Post-Variscan Hydrothermal Veins in Paleozoic Units of the North German Basin

“…Changing tectonic settings, from extensional to divergent movements and the stepwise and long-term subsidence followed by a later inversion of the basin enabled fluid migration along structurally controlled pathways and led to the formation of several hydrothermal vein systems in the NGB [2,[11][12][13][14][15]. The possible fluid sources (e.g., meteoric or magmatic water) and the heat source for the enhanced geothermal gradients are also discussed by these authors.…”

“…age [70]. Schmidt Mumm & Wolfgramm [13,14] suggested a similarity between this hematite mineralization and iron oxide copper gold (IOCG) deposits formed in intracratonic basins. However, the character of the iron ore-forming mechanisms, the direct age of mineralization, and the iron source for the hematite veins remain unknown.…”

Fluid evolution and mineralogy of Mn-Fe-barite-fluorite mineralizations at the contact of the Thuringian Basin, Thüringer Wald and Thüringer Schiefergebirge in Germany

“…The mineralizations on the southern edge of the Thuringian Basin bear a number of similar features to numerous deposits and occurrences throughout post-Variscan Europe, such as deposits in France (Charef & Sheppard 1988;Munoz et al 1994Munoz et al , 2005McGaig et al 2000), Spain (Halliday and Mitchell 1984;Wickham & Taylor 1990;Canals and Cardellach 1993;Galindo et al 1994;Subías and Fernández-Nieto 1995;Johnson et al 1996;Crespo et al 2002;Piqué et al 2008), Sardinia (Muchez et al 2005;Boni et al 2009), Germany (Behr & Gerler 1987;Mertz et al 1989;Boness et al 1990;Lüders & Möller 1992;Meinel 1993;Hähnel et al 1995;Krahn & Baumann 1996;Meyer et al 2000;Zeh & Thomson 2000;Wagner & Lorenz 2002;Schwinn et al 2006;Baatartsogt et al 2007;Staude et al 2007Staude et al , 2011Wagner et al 2010), Poland (Leach et al 1996;Heijlen et al 2003;Schmidt-Mumm & Wolfgramm 2004), Slovakia (Hurai et al 2002(Hurai et al , 2008, Belgium (Slobodnik et al 1994), Hungary (Benkó et al 2014), Czech Republic (Kučera et al 2010), England …”