Geochemistry of Late-Variscan Felsic Igneous Rocks of the Erzgebirge-Vogtland Metallogenic Province

Geochemistry of late-Variscan felsic igneous rocks of the Erzgebirge−Vogtland metallogenic province Part 1 P- and F-rich Li-mica granites Hans-Jürgen Förster GFZ German Research Centre for Geosciences, Section Geoenergy, Telegrafenberg, 14473 Potsdam, Germany Table of contents 1. Citation and License ....................................................................................................................................... 1 2. Abstract .......................................................................................................................................................... 2 3. The data set .................................................................................................................................................... 3 4. Analytical methods ......................................................................................................................................... 6 5. Acknowledgements ........................................................................................................................................ 6 6. References ...................................................................................................................................................... 6 1. Citation and License These data are freely available under the Creative Commons Attribution 4.0 International License (CC BY 4.0). When using the data please cite: Förster, Hans-Jürgen (2021): Geochemistry of late-Variscan felsic igneous rocks of the Erzgebirge−Vogtland metallogenic province. – Part 1: P- und F-rich Li-mica granites. GFZ Data Services, http://doi.org/10.5880/GFZ.4.8.2021.005 The data are supplementary to: Add citation of paper when available 1 FIGURE 1. GEOLOGICAL MAP OF THE ERZGEBIRGE−VOGTLAND METALLOGENIC PROVINCE OF GERMANY IN THE SAXOTHURINGIAN ZONE OF THE CENTRAL EUROPEAN VARISCAN OROGEN. THE EIBENSTOCK MASSIF, THE MOST PROMINENT AND VOLUMINOUS REPRESENTATIVE OF THE GROUP OF P-F-RICH LI-MICA GRANITES, WHICH IS POSITIONED IN THE WESTERN PART OF THE PROVINCE, IS MARKED IN BOLD LETTERS. 2. Abstract This data set is the 1st part of a mini-series assembling whole-rock chemical data for late-Variscan granites of the Erzgebirge−Vogtland metallogenic province in the German Erzgebirge, in the Saxothuringian Zone of the Variscan Orogen, which is dedicated to the group of P−F-rich Li-mica granites. Listed are data from the massifs/plutons of Eibenstock in the western Erzgebirge and Annaberg, Geyer, Pobershau, and Seiffen in the central Erzgebirge (Figure 1). All these occurrences represent composite bodies made-up of texturally and geochemically distinct, but cogenetic sub-intrusions, which are associated with intra- und perigranitic aplitic dykes, pegmatitic schlieren, and frequently mineralized quartz veins and greisens (Tables 1-3). These granites exhibit moderately to strongly elevated concentrations of P, F, Li, Rb, Cs, Ta, Sn, W and U, but are low to very low in Ti, Mg, V, Sc, Co, Ni, Sr, Ba, Y, Zr, Hf, Th, and the REEs. Crystal-melt fractionation was the dominant process controlling the evolution of bulk composition in the course of massif/pluton formation. However, metasomatic processes involving late-stage residual melts and high-T late- to postmagmatic fluids became increasingly more important in highly evolved units and have variably modified the abundances of mobile elements (P, F, Li, Rb, Cs, Ba, Sr). Interaction with the various country rocks and infiltration of meteoric low-T fluids have further disturbed the initial chemical patterns. The data set reports whole-rock geochemical analyses for granites, aplites, and endocontact rocks obtained for the massifs/plutons of Eibenstock, Pobershau, Satzung, Annaberg, and Geyer. Data are provided as separate 2 excel and csv files. The content of the excel sheet and further information on the granites and regional geology are provided in the data description file. 3. The data set The group pf granites presented here is located in the Erzgebirge−Vogtland metallogenic province, in the Saxothuringian Zone of the Variscan Orogen, at the northern edge of the Bohemian Massif (Figure 1). They belong to five massifs/plutons which are multi-phase, composed of several, compositionally and texturally distinct sub- intrusions (Tables 1-3). These late-collisional, late-Variscan (∼ 321−318(315) Ma), ilmenite-series granites of transitional S−I-type affiliation are highly evolved, rich in Si (∼ 72−77 wt% SiO2), F, P, Li, Rb, Cs, W, Sn, and U, moderately to strongly peraluminous (A/CNK ∼ 1.1−1.4), and genetically associated with coeval Sn−W mineralization. Postmagmatic fluids, which interacted with the rocks several Ma after solidification, have caused additional elemental disturbances, preferentially the removal of trioctahedral mica-bound elements (F, Li, Rb, Cs, Sn) and U. The bulk of the analyzed samples experienced overprinting processes associated with different intensities of elemental enrichment or depletion. Within composite massifs, the earliest formed granites are usually, but not always, the least disturbed. Subsurface samples have usually preserved their original magmatic composition better as surface samples, which, for instance, are extensively depleted in U. The petrography, mineralogy, geochemistry, and isotopic composition of the granites of Eibenstock and Pobershau–Satzung have been described in detail by Förster et al. (1999). Comprehensive information on the petrography and mineralogy of granites of the Ehrenfriedersdorf mining district, including those from Annaberg and Geyer; is provided by Hösel (1994). The papers by Förster et al. (1999) and Förster and Romer (2010) contain a representative selection of geochemical data, but the bulk of the analyses remained unpublished. Note that more strongly evolved representatives of this granite group as those dealt with here are exposed in the Podlesí stock, in the Czech part of the province (cf. Breiter et al. 1997). Geochemical data for final aplites/pegmatites and their mineralized equivalents are reported by Lehmann and Seltmann (1995) for the Ehrenfriedersdorf granite system. From this location have also been reported a selection of major and trace element data for melt inclusions in quartz, representing the ultimate differentiates of P−F-rich Li-mica granite-melt fractionation (cf. Webster et al. 1997). The evolution culminated in the formation of pegmatitic melts characterized by melt−melt immiscibility that gave rise to the separation into a peraluminous and peralkaline magma batch (cf. Thomas et al. 2006). The data set published here contains the complete pile of data acquired for the granite occurrences Eibenstock, Pobershau, Satzung, Annaberg, and Geyer. Data are provided as separate excel and csv files. Each file (csv without references) contains the information compiled in Table 4. TABLE 1. INTERNAL STRUCTURE OF THE MULTI-PHASE EIBENSTOCK MASSIF Massif Eibenstock EIB sub-intrusions Sub-intrusion/Variety Texture Abbreviation endocontact fine-grained with aplitic dykes and pegmatitic C-EIB 1 schlieren aplitic very fine-grained A(p) A(i)-EIB 1 most evolved (3) fine-(to medium)-grained, occasionally EIB 3 porphyritic more evolved (2) medium-grained, slightly porphyritic EIB 2 evolved (1) coarse- to medium-grained, serialporphyritic EIB 1 3 least evolved fine- to medium-grained, serial- and E(d)-EIB 1 hiatalporphyritic E(c)-EIB 1 Eb(Wa)-EIB 1 Ea(Kr)-EIB 1 cordierite-bearing sub-facies fine-grained, weakly porphyritic EIB-cord Abbreviations: C = endocontact, A = aplite, A(p) = peri-granitic aplite, A(i) = intra-granitic aplite, E = granite enclave, Ea, Eb etc. indicate the presence of four geochemically and texturally slightly distinct types, with the types A (type Krinitzberg (Kr) in regional literature) and b (type Walfischkopf (Wa) in regional literature) being the most widespread at surface exposure, Eib-cord = special sub-facies of the EIB 1 granite, which locally bears cordierite (suggesting local contamination of metasedimentary country rock), A-EIB 1 resp. E-EIB 1 indicate that the aplite resp. enclave is hosted in the EIB 1 sub-intrusion. TABLE 2. INTERNAL STRUCTURE OF THE MULTI-PHASE POBERSHAU−SATZUNG MASSIF Massif Pobershau POB Satzung SZU subintrusions subintrusions Sub-intrusion Texture Abbreviation Abbreviation most evolved (3) fine-(to medium-) grained, POB 3 SZU 3 more evolved (2) Fine-grained, slightly porphyritic POB 2 SZU 2 to medium-(to coarse)-grained evolved (1) coarse-grained POB 1 least evolved fine- to medium-grained, POB 0 SZU 0 hiatalporphyritic TABLE 3. INTERNAL STRUCTURE OF THE MULTI-PHASE GRANITE OCCURRENCES AT ANNABERG AND GEYER Massif Annaberg ANA Geyer GEY sub-intrusions sub-intrusions Sub-intrusion Texture Abbreviation Abbreviation most evolved (3) fine-grained, rarely porphyritic ANA D GEY D more evolved (2) fine-to medium-grained, ANA C GEY C equigranular evolved (1) medium- to coarse-grained, ANA B serialporphyritic least evolved fine- to medium-grained, ANA A hiatalporphyritic 4 TABLE 4. DESCRIPTION OF COLUMN HEADERS OF THE DATA TABLE Column header unit Definition massif/pluton Name of the massif/pluton (cf. Figure 1) Sub- Name of the sub-intrusion (cf. Tables 1−3) intrusion/Variety Sample No. Sample number Latitude DD, Latitude of the sample location (DD = decimal degree) WGS 84 Longitude DD, Longitude of the sample location (DD = decimal degree) WGS 84 Rechtswert m, Gauss-Krueger East coordinate of the sample location in [m], DHDN GK DHDN (Deutsches Hauptdreiecksnetz) Hochwert m, Gauss-Krueger Nord coordinate of the

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