Peretyazhko, Igor S., Savina, Elena A., Khromova, Elena A. (2017) Minerals of the rhönite-kuratite series in paralavas from a new combustion metamorphic complex in the Choir–Nyalga basin (Central Mongolia): composition, mineral assemblages and formation conditions. Mineralogical Magazine, 81 (4) 949-974 doi:10.1180/minmag.2016.080.144
Reference Type | Journal (article/letter/editorial) | ||
---|---|---|---|
Title | Minerals of the rhönite-kuratite series in paralavas from a new combustion metamorphic complex in the Choir–Nyalga basin (Central Mongolia): composition, mineral assemblages and formation conditions | ||
Journal | Mineralogical Magazine | ||
Authors | Peretyazhko, Igor S. | Author | |
Savina, Elena A. | Author | ||
Khromova, Elena A. | Author | ||
Year | 2017 (August) | Volume | 81 |
Page(s) | 949-974 | Issue | 4 |
Publisher | Mineralogical Society | ||
DOI | doi:10.1180/minmag.2016.080.144Search in ResearchGate | ||
Mindat Ref. ID | 244922 | Long-form Identifier | mindat:1:5:244922:1 |
GUID | d0a1fe82-5e80-47c7-b0bf-1bd26fbb17fa | ||
Full Reference | Peretyazhko, Igor S., Savina, Elena A., Khromova, Elena A. (2017) Minerals of the rhönite-kuratite series in paralavas from a new combustion metamorphic complex in the Choir–Nyalga basin (Central Mongolia): composition, mineral assemblages and formation conditions. Mineralogical Magazine, 81 (4) 949-974 doi:10.1180/minmag.2016.080.144 | ||
Plain Text | Peretyazhko, Igor S., Savina, Elena A., Khromova, Elena A. (2017) Minerals of the rhönite-kuratite series in paralavas from a new combustion metamorphic complex in the Choir–Nyalga basin (Central Mongolia): composition, mineral assemblages and formation conditions. Mineralogical Magazine, 81 (4) 949-974 doi:10.1180/minmag.2016.080.144 | ||
Abstract/Notes | AbstractThis is the first description of rare minerals found in paralavas from a recently discovered combustion metamorphic complex in the Choir–Nyalga basin, Central Mongolia. The identified minerals contain strongly variable concentrations of Si, Ti, Mg, Fe2+ and Fe3+and most commonly have compositions intermediate in a series from kuratite Ca4Fe102+Ti2O4[Si8Al4O 36] and rhönite Ca4(Mg, Fe2+)8Fe23+Ti2O4[Si6Al6O36] to low-Ti kuratite and unnamed Ti-free Fe2+-analogue of rhönite Ca4Fe82+Fe43+O4[Si8Al4O36]. The minerals crystallized in residual Si-Al-K and Si-Al-Ca-Fe immiscible melts after spinel, anorthite–bytownite, melilite, Al-clinopyroxene ± Mg-Fe olivine, together with Fe3+-bearing hercynite, Ca-rich fayalite, kirschsteinite, pyrrhotite ± native iron, wüstite, magnetite, celsian, hyalophane, Ba-orthoclase and fresnoite, but before nepheline± kalsilite, and later sulfates, carbonates, an unidentified 'X-mineral' close to Al- and Fe-rich tobermorite and goethite. Micro-Raman spectroscopy of kuratite shows five bands near 133–155 (strong), 399–401, 545–566, 684–693 (strongest) and 828–839 cm–1.The kuratite-bearing Nyalga paralavas have bulk compositions with MgO/(MgO+FeO+Fe2O3), mol.% ∼0.5 and a CIPW normative ratio of Ne/(Ne+Lc) = 0.23–0.76. Minerals of the rhönite–kuratite series formed during paralava crystallization at ∼1100°C.The diversity of the paralava mineral assemblages might result from local composition variations of Ca-rich silica-undersaturated melts derived from Fe-bearing carbonate-silicate sediments which were affected by nearby coal combustion sources at reducing conditions (IW-WM-QFM buffers) and at a nearly atmospheric pressure. |
Map of Localities
Locality Pages
Mineral Pages
Mineral | Citation Details |
---|---|
Rhönite |
Mineral Occurrences
See Also
These are possibly similar items as determined by title/reference text matching only.