Publication details
Trace elements in garnets of felsic granulites as sediment provenance indicators
| Authors | |
|---|---|
| Year of publication | 2003 |
| Type | Article in Periodical |
| Magazine / Source | Journal of the Czech Geological Society |
| MU Faculty or unit | |
| Citation | |
| Field | Geology and mineralogy |
| Keywords | garnet chemistry; trace elements; granulites; foreland basin; provenance; Bohemian Massif; European Variscides |
| Description | The Lower Carboniferous Culm Basin is part of the larger European Variscan foreland basin. The youngest sediments of the Myslejovice Formation contain heavy mineral assemblages dominated by pyrope-almandine garnets. This paper compares the major element (electron microprobe) and trace element (LA-ICP-MS) compositions of detrital pyrope-almandine garnets from the Luleč Conglomerates with garnets from selected granulites of the Czech Massif for the purpose of studying the provenance of the Culm sediments. Detrital low grossular pyrope-almandine garnets can only be matched with some granulites and leptynites of the Bohemian Massif. At the present-day level of erosion of the Bohemian Massif, granulite garnets have higher calcium and/or lower magnesium concentrations. The compositions and zoning patterns of pyrope-almandine garnets from the Luleč quarry compare well with granulite garnets from the Miroslav Crystalline Unit and small Moldanubian granulite bodies west of Jihlava. Pyrope-almandine garnets from leptynites of the Polička Crystalline Unit and the Náměšť Granulite Massif show large differences in REE patterns. The results indicate that the sediment provenance may well have been changing during the deposition of the Luleč Conglomerates. |