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Igneous refinement of quartz raw materials. Rune B. Larsen Francois Jacamon Bjorn Eske Sorensen Norwegian University of Science and Technology Peter M. Ihlen Axel Müller Geological Survey of Norway. High purity quartz High end products Silica glasses Optical lenses, light bulbs
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Igneous refinement of quartz raw materials Rune B. Larsen Francois Jacamon Bjorn Eske Sorensen Norwegian University of Science and Technology Peter M. Ihlen Axel Müller Geological Survey of Norway • High purity quartz • High end products • Silica glasses • Optical lenses, light bulbs • Fibres,insulators • Polycrystalline silica • Solar grade silica (?) GSA, Salt Lake City, 2005
Trace elements in qz, which, where and why ? • Typical abundance in igneous quartz • Analytical approach • Melt composition, igneous evolution qz-comp. • Subsolidus modification
LA-ICP-MS is the preferred analytical method Al: <10 – 1000 Ti: <1 – 200 Li: <1 – 30 P: <1 – 30 K: <5 – 20(?) Fe: <1 – 20 B: <1 – 10(?)
Charnockitic pyroxene-granite Pyroxene-hornblende granite Hornblende granite Hornblende-biotite granite Biotite granite A-TYPE GRANITIC ROCKS - CHARNOCKITES High T Low T Pedersen, 1988
Al Li Ti P Ge Be Bi-granite Pyr- Hbl- 0.05
Pyr-granite Pyr-Hbl granite Hbl-granite1 Hbl-granite 2 Hbl-Bi granite 1 Hbl-Bi granite 2 Bi-granite 1 Bi-granite 2 Aluminium Lithium Aluminium and lithium behaviour
Pyr-granite Pyr-Hbl granite Hbl-granite1 Hbl-granite 2 Hbl-Bi granite 1 Hbl-Bi granite 2 Bi-granite 1 Apatite out? Bi-granite 2 PHOSPHORUS
S-TYPE PERALUMINOUS GRANITES Müller et al., 2002 Podlesi, Czech Republi
Primary Qz Early Secondary Qz Late Secondary Qz
Igneous differentiation form quartz with low Ti, Fe, K and B contents. Ge and Li is increasing. P and Al may also increase Peraluminous granites, form qz with high Al contents. Evolved metaluminous granitic qz is low in this element Largely, the quartz composition is buffered by the melt composition Li, B, Al and Fe is lowered during hydrothermal recrystallization K is not seriously influenced. The Na concentration may increase markedly Ti, Ge and P are normally immobile during recrystallization Qz is quite robust during subsolidus weathering and may largely preserve igneous fingerprint Accordingly, qz partially preserve the igneous history and distinguish magmatic events in igneous complex terrains Granitic pegmatite, particularly metaluminous and hydrothermally infiltrated GP’s are promising targets for HPQ prospecting GSA, Salt Lake City, 2005, Rune B. larsen