Genese und Herkunft von Gold-Nuggets aus dem Guli Massiv, Nordsibirien, Russland: eine multidisziplinäre mineralogische und geochemische Studie
Research output: Thesis › Doctoral Thesis
The Guli Massif occupies an area of about 2000km2 within the Maimecha-Kotui province in the northern part of the Siberian platform (Taimyr Province, Russia). The Massif is composed of dunite core complex, an alkali-ultramafic sequence and of two carbonatite intrusions. The Massif is characterised by occurrences of PGE and Au-placer deposits, as well as REE and phlogopite mineralisations. The nuggets have a grain-size in the range of 0.25 to 1mm, show a roundness between angular and well rounded and a sphericity between 0.3 and 0.9. This indicates a maximum transport distance from the source in the range of 10-20km. Chemically the nuggets are pure gold, argentian, electrum and tetra-auricupride. The nuggets are characterised by a great variety of solid inclusions. Clinopyroxene, olivine, amphibole and phlogopite dominate among the silicate inclusions, oxide, REE minerals, calcite sulfide and apatite had been identified. The mineralogy of these inclusions indicates a derivation of the gold nuggets from an alkaline rock suite. In order to tackle the question of the source of the gold in more detail, the second part of this study aims on the alkali-ultramafic-sequence of the Guli Massiv. A detailed mineralogical-petrological and geochemical investigation was carried out. The mineralogy and the compositional characteristics of the rocks of the alkali-ultramafic-sequence and those of the inclusions in the Au-nuggets are in good accordance. Therefore, it can be concluded that the gold was derived from the alkali-ultramafic-sequence.
|Translated title of the contribution||GENESIS AND DERIVATION OF Au-NUGGETS FROM THE GULI MASSIV, NORTHERN SIBERIA, RUSSIA: A MULTIDISCIPLINARY MINERALOGICAL AND GEOCHEMICAL STUDY|
|Publication status||Published - 2007|