Major and minor elemental trends of gypsum-ghost limestones of the Osiek-Baranów Sandomierski native sulphur deposit (northern Carpathian Foredeep, Poland): implications for limestones genesis

The Middle Miocene (middle Badenian) "gypsum-ghost" limestones composed of calcite and/or sulphur pseudomorphs after selenitic gypsum, are a salient feature of the Polish sulphur deposits from the northern Carpathian Foredeep (S. Poland). Sulphurous rocks (including the gypsum-ghost limestones) are present within the evaporite unit, the so-called "Chemical Series", and are commonly believed to be lithological equivalents of synchronous gypsum deposits, resulting from regionally extensive, wholesale replacement of the sele-nite lithofacies by limestones and limestone + native sulphur. However, detailed geochemical examination of regional major and minor element compositions in these unusual carbonates suggests considerable internal differences. Distinct variations in chemical distribution along the main development of the Osiek-Baranów Sandomierski native sulphur deposit, together with the associated barren limestone areas, are clearly recognized. The pattern of the geochemical parameters of these gypsum-ghost limestones is inconsistent with an epigenetic model of formation of the Polish sulphur deposits (wholesale replacement of sulphate deposits by carbonates + native sulphur) and argues for their formation within a sedimentary-early diagenetic regime.