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Soil development in a coal-burning environment : the Upper Silesian waste heaps of Poland

100%

Kruszewski Ł. , Kisiel M. , Cegiełka M.

Geological Quarterly

2021

tom Vol. 65, No. 2

art. no. 24

Soil development in burning coal-mining waste heaps is a rarely addressed phenomenon, especially in Poland and in relation to pyrometamorphic substrates. Eight samples were collected from 5 heaps, four of them obtained from Europe‘s highest “Szarlota” heap located in Rydułtowy. Traces of pedogenesis were observed in both thermally changed (pyrometamorphic) and megascopically unchanged substrates. Grain size distribution is variable, with the finest silt being most clearly associated with distinct, though modest, trace element (TE) enrichment, primarily of Sb, As and Pb, and Ba and Cu. Slight variations in soil mineralogy occur even in samples derived from various parts of the “Szarlota” heap. Goethite, however, is a frequent component in most samples studied; it is an important pedogenesis factor in the soils studied and seems to be correlated with salinity. To some extent, it also influences TE composition. Relatively invariable pH, moderate TE and nutrient contents, and a lack of Alw allows vegetation growth at most of the locations studied.

Ba-Fe titanates in Peralkaline granite of the Ilímaussaq Complex, South Greenland

88%

Cegiełka M. , Bagiński B. , Macdonald R. , Marciniak-Maliszewska B. , Stachowicz M.

Acta Geologica Polonica

2022

tom Vol. 72, no. 1

1--8

A peralkaline granite of the Ilímaussaq Complex, South Greenland, contains the rare mineral henrymeyerite [(Ba0.92Na 0.05Ca0.03) 1.0(Ti6.87Fe2+1.04Nb 0.03)7.9O 16], a low-Fe Ba titanate [(Ba0.74 Ca0.02Na 0.05) 0.8 (Ti4.9o Fe2+0.15Nb 0.04)5.1O 11], and an unidentified Ba titanosilicate. Both titanates show the coupled substitution 2Na+ + Si4+→ Ba2+ + Ti4+. The minerals are present as tiny crystals fringing ilmenite inclusions in an amphibole crystal and are thought to have formed during the hydrothermal stage of the granite’s evolution.

Zirconium silicates in a peralkaline granite: a record of the interplay of magmatic and hydrothermal processes (Ilímaussaq complex, Greenland)

75%

Cegiełka M. , Bagiński B. , Macdonald R. , Belkin H. E. , Kotowski J. , Upton B. G. J.

Acta Geologica Polonica

2022

tom Vol. 72, no. 2

235--245

Compositional and textural data are presented for zircon, secondary Zr-silicates, catapleiite and elpidite in a peralkaline granite from the Ilímaussaq complex, south Greenland. The zircon is essentially stoichiometric, with (Zr + Hf + Si) = 1.96–1.98 a.p.f.u. The secondary Zr-silicates show a wide range of Zr/Si atomic ratios (0.13–0.79). The catapleiite varies from close to stoichiometric to a Na-depleted type showing cation deficiency (5.2–5.8 a.p.f.u.). Elpidite shows similar variations (7.2–9.0 a.p.f.u.). Textural relationships between the Zr phases are interpreted to show that magmatic zircon interacted with hydrous fluids exsolved from the magma to form the secondary Zr-silicates. Formation of catapleiite was late-magmatic, in equilibrium with a Na-Si-bearing fluid. This was followed by the crystallization of elpidite, the fluid having a different Na/Si ratio. Both catapleiite and elpidite experienced Na-loss during late-stage hydrothermal alteration.