Post-Variscan structurally-controlled hydrothermal Zn-Fe-Pb sulfide and F-Ba mineralization in deep-seated Paleozoic units of the North German Basin: A review

Nadoll P, Sosnicka M, Kraemer D, Duschl F (2019)


Publication Type: Journal article, Review article

Publication year: 2019

Journal

Book Volume: 106

Pages Range: 273-299

DOI: 10.1016/j.oregeorev.2019.01.022

Abstract

Hydrothermal Zn-Pb-Fe sulfide and F-Ba mineralization occur as open space fillings, veins, and fracture coatings in various parts of the North German Basin in Paleozoic sedimentary rocks and volcanic units at depths of up to four kilometers. We present a petrographic and geochemical (fluid inclusion, mineral and formation water geochemistry) inventory of the mineralized zones and review the basin architecture, evolution, and stratigraphy in order to decipher the timing, extent, fluid pathways, and fluid-rock interactions associated with the ore formation. A particular focus lies on the sediment-hosted Zn-Fe-Pb sulfides in the western part of the North German Basin, the Lower Saxony Basin. Samples from hydrothermal veins from the Pre-Permian basement are also being investigated and compared to the North German Basin-style mineralization to uncover possible genetic links between them. The sediment-hosted sulfide mineralization in the Lower Saxony Basin in the Permian Stassfurt Carbonate unit (Ca2) shares many characteristics that are typical for carbonate-hosted base metal sulfide deposits such as MVT deposits. Petrographic observations, fluid inclusion and isotope data provide evidence that Zn-Fe-Pb sulfides were deposited by highly saline metal-rich basinal brines at temperatures of similar to 160 degrees C. Carbon and oxygen isotope data point toward fluid mixing augmented by structurally-controlled fluid migration during the late Cretaceous basin inversion as the primary ore precipitation mechanism with no magmatic component. In the Altmark-Brandenburg Basin, steeply-dipping F-Ba (calcite, anhydrite, quartz) veinlets in Permo-Carboniferous sandstones and volcanic units are evidence for enhanced post-Variscan structurally-controlled fluid flow. Sulfides are, apart from rare occurrences of chalcopyrite, absent. This is interpreted to reflect the paleogeographic position of the Altmark-Brandenburg Basin (deeper paleogeographic basin position without carbonate aquifers), the lack of reductants, and the predominance of nitrogen-rich fluids as documented by fluid inclusions. Measurements on formation waters from the NGB show geochemical similarities to fluid inclusions in ore and gangue minerals and could represent a potential future exploration tool for hydrothermal ore deposits. This has the potential to aid future research and exploration of deeply covered sediment-hosted deposits and to meet future mineral resources demands.

Authors with CRIS profile

Involved external institutions

How to cite

APA:

Nadoll, P., Sosnicka, M., Kraemer, D., & Duschl, F. (2019). Post-Variscan structurally-controlled hydrothermal Zn-Fe-Pb sulfide and F-Ba mineralization in deep-seated Paleozoic units of the North German Basin: A review. Ore Geology Reviews, 106, 273-299. https://dx.doi.org/10.1016/j.oregeorev.2019.01.022

MLA:

Nadoll, Patrick, et al. "Post-Variscan structurally-controlled hydrothermal Zn-Fe-Pb sulfide and F-Ba mineralization in deep-seated Paleozoic units of the North German Basin: A review." Ore Geology Reviews 106 (2019): 273-299.

BibTeX: Download