Carbonate-cemented stylolites and fractures in the Upper Jurassic limestones of the Eastern Iberian Range, Spain: A record of palaeofluids composition and thermal history

Dolomite and calcite cements fill open stylolites, fractures and “pipe-shaped” structures related to faulting in Tithonian-Berriasian limestones of the Maestrat Basin in the Iberian Range (Spain) Due to the grater susceptibility of the dolomitised limestones to brittle fracturing during the Alpine tectonism, their location and distribution may have important implications for hydrocarbon prospectively within the studied region (Iberian Range). Three generations of structures were recognised (open stylolites, extensional fractures and faults) based on field observations, cross-cutting relationships and cement mineralogy. Petrographic, cathodoluminesence and geochemical analyses (electron microprobe, fluid inclusion, oxygen, carbon and strontium isotopes) of the carbonates helped unravel the origin and evolution of the fluids, from which these carbonates have been precipitated. These cements occur in the following structures: