Resumen de Dolomías relacionadas con fallas durante la etapa de rift Jurásico superior-Cretácico inferior en la subcuenca de la Salzedella (Cuenca del Maestrazgo, Cadena Ibérica)
A set of high angle normal faults control the geometry of dolomite bodies (Fm. Dolomias de lasTalaies) that occur in the Upper Jurassic-Lower Cretaceous synrift deposits in the Salzedella subbasin (Maestrat Basin). There are three main dolomite types: isolated rhombohedral dolomite, replacement dolomites and dolomite cement.The mineralogy and geochemical composition of the three types of dolomites is similar. The 8,80 values of replacement dolomites (-6.3 %o PDB) are slightly lighter than the values forlimestone host rocks (-4.2 %o PDB). The 87Sr/18Sr values of the replacement dolomites (0.70740-0.70798) are equivalent to Triassic and Liassic marine seawater values. The fluid inclusion data(Th=115 °C, Tmi=-16 a -21 °C) represent high temperature fluids and a salinity of 19 to 23 %wt. NaC! eq. The source of the Mg most likely is Triassic and Liassic evaporite units. The assumed dolomitization model is based on a combination of a topographic and advection driven flow system. Meteoric waters descend along the basin margins to the Triassic and Liassic evaporite levels, where they mix with connate waters and ascend due to increased heat flows at the end of the rift stage.
