This data set is Part 9 of a series of data sets dealing with the composition of accessory minerals from felsic igneous rocks compiles chemical data for monazite-(Ce), xenotime-(Y) and zircon from several, late-Variscan granite occurrences in the Aue-Schwarzenberg Granite Zone (ASGZ) located in the Western Erzgebirge−Vogtland metallogenic province of Germany. The rocks treated in this data set encompass the biotite granites of the Aue suite, Bernsbach and Beierfeld, and the two-mica granites from Lauter and the Schwarzenberg suite. The data set contains the complete pile of electron-microprobe analyses for monazite-(Ce) (MONA-ASGZ-2021), xenotime-(Y) (XENO-ASGZ-2021) and zircon (ZIRC-ASGZ-2021). Tables are presented as Excel (xlsx) resp. machine-readable csv formats. The content of the tables and further information on the granites and regional geology are provided in the data description file and the supplementary literature. The ASGZ (about 325 Ma) is located within the deep-reaching Gera-Jáchymov Fault Zone and includes the F-poor biotite granites of the Aue suite (including the granite occurrences at Schlema-Alberoda, Aue, Auerhammer, and Schneeberg), Bernsbach and Beierfeld, and the F-poor two-mica granites of the Schwarzenberg suite (covering the granite occurrences at Schwarzenberg, Neuwelt, and Erla) and Lauter (Fig. 1). The granite encountered by drilling at the village Burkersdorf does not represent an independent intrusion, but is instead a subsurface exposure of the westerly Kirchberg granite, at the contact to the metamorphic country rock. The petrography, mineralogy, geochemistry, isotopic composition, and geochronology of the ASGZ rocks have been comprehensively described by Förster et al. (2009). The paper of Förster (2010) reports a selection of results of electron-microprobe analyses of monazite-(Ce), xenotime-(Y) and zircon, but the bulk of the obtained data remained unpublished. This paper also provides a mineralogical mass-balance calculation for the lanthanides and actinides of the Aue and Schwarzenberg granite suites and a selection of back-scattered electron images displaying the intergrowths, texture, and alteration patterns of the radioactive and REE-Y-Zr-bearing accessory species. The F-poor biotite granites of the ASGZ are weakly to mildly peraluminous (A/CNK = 1.07 – 1.14; SiO2 = 70 – 76 wt.%). The F-poor two-mica granites are mildly to strongly peraluminous (A/CNK = 1.17 – 1.26) and cover a similar range in silica concentration (69 – 77 wt%). From this granite group, only more fractionated, higher evolved sub-intrusions were subjected to the study of accessory-mineral composition. Some granites of this zone are genetically related with ortho-magmatic W-Mo veins and para-magmatic vein-type U mineralization.
This data set is the sixth part of a series reporting chemical data for accessory minerals from felsic igneous rocks. It assembles the results of electron-microprobe spot analyses of monazite-(Ce), xenotime-(Y) and zircon from the late-Variscan granites of the Fichtelgebirge/Smrčiny in the Saxothuringian Zone of the Variscan Orogen in Germany/ Czech Republic.The granites form an older, Namurian intrusive complex (OIC-p and OIC-e) and a younger, post-Westphalian intrusive complex (YIC-1 and YIC-2). Both complexes have distinct radioactive accessory-mineral assemblages and compositions. The OIC-p biotite monzogranites contain monazite-(Ce) and minor thorite, but apparently lack magmatic xenotime-(Y) and uraninite. The more evolved OIC-e two-mica granites bear monazite-(Ce) occasionally rich in Th (up to 21 wt% ThO2) and U (8 wt% UO2), xenotime-(Y) of moderate U content (< 3.3 wt% UO2), and uraninite poor in Th and the REE. The most fractionated YIC Li-mica granites (YIC-2) may contain monazite extremely high in Th (40.5 wt% ThO2) and U (8.6 wt% UO2), which classify as cheralite-(Ce), xenotime-(Y) rich in U (6.3 wt% UO2) and such with elevated Y/Ho ratios (up to 48), and also a Th–REE-poor uraninite. In these granites, zircon may contain up to 5 wt% HfO2 and display low, fractionated Zr/Hf ratios (down to 10).The data set contains the complete pile of electron-microprobe analyses for monazite-(Ce) (MONA-FICH-2020), xenotime-(Y) (XENO-FICH-2020), and zircon (ZIRC-FICH-2020). All tables are presented as Excel (xlsx) and machine-readable txt formats. The content of the tables and further information on the granites and regional geology are provided in the data description file.
Part seven of a series of data sets dealing with the composition of accessory minerals from felsic igneous rocks reports chemical data for monazite-(Ce) and zircon from eight occurrences of high-Si felsic microgranites/rhyolites in the Erzgebirge−Vogtland metallogenic province of Germany, which possibly emplaced between 305 and 295 Ma. The subvolcanic rocks are discriminated into three groups according to whole-rock geochemistry. Mineral data are acquired between about 1995 and 2005 on surface rocks and borehole samples. The data set contains the complete pile of electron-microprobe analyses for monazite-(Ce) (MONA-VOLC-2020) and zircon (ZIRC-VOLC-2020). All tables are presented as Excel (xlsx) and machine-readable csv formats. The content of the tables and further information on the granites and regional geology are provided in the data description file. Information on xenotime-(Y), which is commonly rare and did not precipitate in all rhyolites, and rhabdophane-(Ce), which was observed only ones as alteration product of monazite-(Ce), is provided elsewhere (cf. data description file).
This data set is the 4th contribution of a series reporting chemical data for accessory minerals from felsic igneous rocks. It deals with two late Variscan biotite-granite massifs emplaced in the Saxothuringian Zone of the Variscan Orogen (Erzgebirge−Vogtland metallogenic province) in Germany. Mineral compositions were measured by electron-microprobe on surface rocks and borehole samples.The data set assembles the results of electron-microprobe spot analyses of primary and secondary allanite-(Ce), monazite-(Ce), xenotime-(Y) and zircon from the multi-phase biotite-granite plutons of Kirchberg (KIB, Western Erzgebirge) and Niederbobritzsch (NBZ, Eastern Erzgebirge). Both plutons comprise several, compositionally and texturally distinct sub-intrusions, contain locally centimeter- to decimeter-sized co-genetic enclaves and xenoliths, and are cross-cut by chemically distinct, fine-grained aplitic dikes. These late-Variscan (c. 325 Ma) granites are moderately to highly evolved and (not considering enclaves) span the SiO2-range (in wt%) 67.0-77.4 (KIB) and 66.8-76.2 (NBZ). The granites are weakly peraluminous (A/CNK = 1.04−1.11 for KIB and 0.99-1.10 for NBZ) and of transitional I−S-type affinity.Formation of primary allanite-(Ce) was restricted to the least-evolved subintrusions KIB1 and NBZ1 of both massifs. All other granites contain monazite-(Ce) as predominant LREE host. Magmatic allanite-(Ce) is variably altered and characterized by totals <100 wt%, implying the presence of several wt% water in the structure. Synchysite-(Ce) constitutes one of its alteration minerals. The Kirchberg massif hosts a second sub-facies of KIB1 that contains monazite instead of allanite as primary species. Severe alteration of this granite facies gave rise to partial or complete dissolution of part of the monazite accompanied by formation of allanite-epidote solid solutions as alteration product. Monazite-(Ce) displays large variations in Th versus REE concentrations even at thin-section scale. Incorporation of Th is mainly governed by the huttonite substitution Th^4+ + Si^4+ = REE^3+ + P^5+. Thorium concentrations span the range 1.33 – 41.8 wt.% ThO2. Xenotime-(Y) does not occur in KBI1 and NBZ1, but crystallized in all other subintrusions. Notable is the predominance of the heaviest REE Er-Lu (normalized to chondrite).The data set contains the complete pile of electron-microprobe analyses for the four accessory minerals allanite-(Ce) (ALLA-KIB-NBZ2019), monazite-(Ce) (MONA-KIB-NBZ2019), xenotime-(Y) (XENO-KIB-NBZ2019) and zircon (ZIRC-KIB-NBZ2019). All tables are presented as Excel (xlsx) and machine-readable csv formats. The content of the tables and further data description are given in the data description file, together with BSE images of primary and secondary allanite-(Ce) from the KIB1 subintrusion.
This data set is the 5th fifth part of a series reporting chemical data for accessory minerals from felsic igneous rocks. Most data refer to plutonic rocks from the Saxothuringian Zone of the Variscan Orogen (Erzgebirge−Vogtland metallogenic province) in Germany performed between about 1995 and 2005 on surface rocks and borehole samples.This data set assembles the results of electron-microprobe spot analyses of monazite-(Ce), xenotime-(Y) and zircon from two concealed, genetically distinct occurrences of evolved, F-rich Li-mica granite, that are the transitional S-I-type P-rich granites of Pobershau-Satzung (POB-SZU) and the P-poor granite of Seiffen (SEI), a representative of the class of aluminous A-type granites.Of all three species, grains of abnormal composition are present, reflecting the evolved nature and specific composition of their granite hosts. The most striking differences in mineral composition between the two granite occurrences are displayed by a) the substitution reaction governing the incorporation of Th+U in monazite (cheralite substitution, Ca(Th,U)REE-2, in POB-SZU and huttonite substitution, Th(U)SiREE-1P-1, in SEI) and b) the chondrite-normalized REE patterns of xenotime (peaking at Tb-Dy in POB-SEI and Yb-Lu in SEI).The data set contains the complete pile of electron-microprobe analyses for monazite-(Ce) (MONA-POB-SEI-NBZ2019), xenotime-(Y) (XENO-POB-SEI2019), and zircon (ZIRC-POB-SEI2019). All tables are presented as Excel (xlsx) and machine-readable csv formats. The content of the tables and further information on the granites and regional geology are provided in the data description file.
This data set is the third of a series reporting chemical data for accessory minerals from felsic igneous rocks. It compiles the results of electron-microprobe spot analyses of monazite-(Ce) from various Paleoproterozoic granitoids and spatially associated gneisses located in the wider Fort McMurray area in northeastern Alberta, Canada. The data were generated in connection with the Master of Science thesis of Nathanial John Walsh (Walsh 2013) at the Department of Earth and Atmospheric Sciences of the University of Alberta, Edmonton, Canada, but remained unpublished. The thesis was part of the Helmholtz - Alberta - Initiative (HAI) between the University of Alberta and the Helmholtz Association.Interestingly, monazite from the diverse basement rocks display various kinds of pattern with respect to composition and origin. The great bulk of measured grains display variably declined chondrite-normalized LREE patterns virtually free of anomalies indicative for significant fluid-induced overprinting. We have rocks characterized by largely unzoned, chemically homogeneous grains. There are as well rocks containing nicely patchy-zoned grains showing a wide range in composition, in particular regarding the Th/LREE proportions. Here, maximum measured Th concentration amounted to 33 wt% ThO2. Incorporation of Th into the crystal structure is almost exclusively governed by the huttonite substitution reaction, i.e., Th^4+ + Si^4+ = REE^3+ + P^5+, as characteristic for this chemical type of granites (Förster 1998). The suite of rocks also included samples containing small-sized inclusions of Th-poor monazite in apatite, which formed in response to metamorphic, fluid-aided dissolution-reprecipitation processes (Harlov and Förster 2003, Harlov et al. 2005). Finally, we have a quartz monzonite containing Th-poor monazite in apatite together with matrix monazite of normal Th concentration, the origin if which is not yet fully resolved (cf. Foerster-2018-004_monazite-alberta-BSE images.pdf. presenting back-scattered electron images of monazite grains). In brief, the data set provides information on several aspects of formation and alteration of monazite in non-metamorphic and metamorphic granite.The data set published here contains the complete pile of data acquired for monazite-(Ce) and back-scattered electron (BSE) images of many of the probed grains. Chemical data are provided as Excel and machine-readable .csv files, which contain the information listed in Table 1 of the data description file. Column headers in red (only in the Excel version) indicate that the data and information provided in these columns is from Walsh (2013). “0.00” means that the concentrations of the respective elements were measured, but were below their limits of detection. Blank boxes in oxide concentrations columns indicate that the respective elements were not sought. The collection of BSE images is presented as pdf.file. The sample and grain numbers are given below each mineral image and are corresponding to the Sample No. and the Grain No. in the data table.The thesis of N. Walsh "Walsh, N.J. (2013) Geochemistry and geochronology of the Precambrian basement domains in the vicinity of Fort MacMurray, Alberta: a geothermal perspective. Master of Science thesis, Department of Earth and Atmospheric Sciences, University of Alberta, Canada" is not available online.
This data set is the second part of a series reporting chemical data for accessory minerals from felsic igneous rocks. Most data refer to plutonic rocks from the Saxothuringian Zone of the Variscan Orogen (Erzgebirge−Vogtland metallogenic province) in Germany performed between about 1995 and 2005 on surface rocks and borehole samples. This data set assembles the results of electron-microprobe spot analyses of monazite-(Ce), xenotime-(Y) and zircon from the Li-mica granite massif of Eibenstock. This massif is composed of several, compositionally and texturally distinct sub-intrusions. Least evolved members of the fractionation series are exposed as variably sized enclaves. The pluton is cross-cut by fine-grained aplitic dikes. These late-Variscan (c. 318−320 Ma) granites are highly evolved, rich in Si (72.4-75.8 wt% SiO2), F, P, Li, Rb, Cs, and Sn, mildly to strongly peraluminous (A/CNK = 1.14−1.35), of transitional S−I-type affinity, and spatially and genetically associated with coeval significant Sn−W−(Mo) mineralization. Most notably, a comparatively large population of grains of all three species is distinguished by abnormal composition, reflecting the chemically evolved nature of their hosts. Probe data indicate that the composition of monazite-(Ce) and zircon changes with fractionation-driven evolution of magma chemistry. Monazite-(Ce) composition extends over an abnormally large range. In the course of magma differentiation, mineral chemistry evolves towards enrichment Th and U and development of flattened and kinked chondrite-normalized LREE patterns, with negative anomalies at La or Nd, or both (also known as lanthanide tetrad effect). Many grains are so rich in Th that they classify as cheralite-(Ce). The concentrations (in oxide wt%) of the radionuclides Th and U maximizes to 51.7 and 5.3, respectively. The maximum concentration of Y amounts to 4.7 wt% Y2O3. Composition of zircon displays a large variability. A greater number of grains or domains are distinguished by abnormal enrichment in (in oxide wt%) P (up to 9.6), Th (up to 12.2), U (up to 8.7), Hf (up to 5.6) Al (up to 2.2), Sc (up to 2.0), Y (up to 7.0), HREE and Y. Enrichment in these elements is usually associated with low analytical totals, reflecting precipitation from volatile-rich magmas and/or their interaction with, and alteration by, late-magmatic fluids. Xenotime-(Y) chemistry is comparatively little sensitive to changes of Eibenstock-magma composition relative to what has been observed for monazite-(Ce) and zircon. The U concentrations in xenotime-(Y) are generally high and maximize to 6.7 wt% UO2. Chondrite-normalized MREE and HREE patterns preferentially in xenotime-(Y) from more evolved magma batches mimic that of their host granites in that they are (a) inclined from Tb-Dy towards Lu, (b) partially evolved the lanthanide tetrad effect, and (c) display above-CHARAC Y/Ho ratios up to 41. The data set published here contains the complete pile of data acquired for these three accessory minerals. Data are provided as three separate excel files, one for each species (monazite-(Ce); xenotime-(Y); zircon). The data are described in detail in the associated data description file.
The Ries impact structure in Southern Germany is one of the best-preserved impact structures on Earth. Melt-bearing impact breccia appears in a variety of well accessible exposures around the inner ring up to 10 km beyond the crater rim (so-called outer suevite) overlying a ballistically ejected lithic breccia (so-called ‘Bunte Breccia’). Occasionally individual melt bombs occur in the ‘Bunte Breccia’. Coherent impact melt rock outside the inner crater is located in the eastern megablock zone (Stöffler et al., 2013 and references therein).This data set comprises major and trace element geochemistry of samples from eight outer suevite exposures, one impact melt rock exposure, and one melt bomb of the Ries impact crater. Two analytical method approaches were performed: i) in-situ analysis using electron microprobe (EMP) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and ii) analysis of whole-rock, melt separates, and suevite matrix separates using X-ray fluorescence (XRF), and inductively coupled plasma atomic emission spectroscopy (ICP-AES)/ inductively coupled plasma mass spectrometry (ICP-MS).
This data set compiles the results of electron-microprobe spot analyses of monazite-(Ce), xenotime-(Y) and zircon from the two-mica granite massif of Bergen. This massif is composed of compositionally and texturally distinct sub-intrusions, which occasionally contain dark microgranular enclaves and are cross-cut by aplitic dikes. These late-Variscan (c. 325 Ma) granites are evolved, Si-rich (70.6−76.3 wt% SiO2), of transitional I−S-type affinity, and spatially associated with minor W−Mo mineralization.Data indicate that the composition of monazite-(Ce) and zircon changes with fractionation-driven evolution of magma chemistry. In the course of magma differentiation, monazite-(Ce) chemistry evolves towards enrichment Th and U and development of “irregular” chondrite-normalized LREE patterns, with negative anomalies at La or Nd, or both. Monazite-(Ce) precipitated from more evolved magma batches also tends to be richer in MREE and HREE relative to that occurring in early-stage granites. Composition of zircon in more differentiated sub-intrusions displays a large variability. A greater number of grains or domains are distinguished by enrichment in P, Hf, Al, Sc, Y+HREE and low analytical totals, reflecting their crystallization from volatile-rich magmas and/or their interaction with late-magmatic fluids. Xenotime-(Y) chemistry is comparatively insensitive to changes of magma composition that characterized the Bergen massif.The data set published here contains the complete pile of elecron-microprobe analyses for the three accessory minerals monazite-(Ce) (MonaBrg2018), xenotime-(Y) (XenoBRG2018) and zirkon (ZircBRG2018). All tables are presented as Excel (.xlsx) and csv formats. The content of the tables and further data description are given in the data description file.
Electron-microprobe analyses (Table 5) were completed on a selection of grains from 11 samples, with a CAMECA SX-50 instrument (University of Louvain-la-Neuve, Belgium), under an accelerating voltage of 15 kV and a probe current of 20 nA. The standards used were the Kabira graftonite (Fe, Mn, P; Fransolet, 1975), corundum (Al), olivine (Mg), wollastonite (Si), and willemite (Zn).
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