Original scientific paper

Ferromanganese Coated Structures from the Jabuka Pit (Central Adriatic): Mineralogical, Geochemical and Genetic Considerations

Tadej Dolenec ; Department of Geology, Faculty of Natural Sciences and Engineering, University of Ljubljana, Aškerčeva 12, 1000 Ljubljana, Slovenia and Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia

Abstract

One of the most interesting features of the Jabuka Pit, a depression up to 275 m deep in the Central Adriatic is the presence of ferromanganese crusts and coatings found on various mollusks shells, shell fragments and other biogenic detritus exposed to seawater. They are composed mostly of Fe-poor and Mg-rich 10 Å manganates. 10 Å manganates also form collomorph-banded and botryoidal aggregates, as well as 1.5 mm high stalactitic structures composed of up to 5 µm long plate-like crystals. Their hydrogenous precipitation at the sediment- water interface in oxygenated conditions is hypothesised.

Keywords

ferromanganese coating structures; 10 Å manganates; SEM and EDS; geochemistry; Jabuka Pit; Central Adriatic

Hrčak ID:

103170

URI

https://hrcak.srce.hr/103170

Publication date:

29.8.2003.

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