Journal of geochemical exploration vol:78-9 pages:607-611
Polysulphide mineralisation in the Lower Palaeozoic of the Anglo-Brabant Fold belt is the subject of a detailed sulphur isotopic investigation to constrain possible sulphur sources. A distinction can be made between sedimentary pyrite, with low delta(34)S values and identified as pyrite with a bacteriogenic origin, and pyrite with high delta(34)S, formed during hydrothermal circulation along strain zones. Both kinds of pyrites are present in the important orogenic mesozonal polysulphide mineralisation in the Marcq area. The hydrothermal sulphur is presumed to be H2S released through thermal decomposition of kerogen present in Lower Palaeozoic strata. Pyrite with intermediate delta(34)S values occurs in less important strain zones. These values are explained by mixing of hydrothermal sulphur and sulphur with a sedimentary origin. (C) 2003 Elsevier Science B.V. All rights reserved.