Tracking the Origin and Evolution of Diagenetic Fluids of Upper Jurassic Carbonate Rocks in the Zagros Thrust Fold Belt, NE-Iraq

Utilizing sophisticated tools in carbonate rocks is crucial to interpretating the origin and evolution of diagenetic fluids from Upper Jurassic along Zagros thrust-fold Belt. The paleofluids utilizing in-situ strontium isotope ratios by high resolution laser ablation ICP-MS, integrated with stable isotopes, petrography fieldwork are constrained. Due lack information on chemistry fluids, cements that filled were analysed fractures pores. This allowed us trace a sequence, which defined at beginning sediment deposition (pristine facies). Based geochemistry (oxygen-, carbon- strontium-isotope compositions) two major stages involving identified. initial stage, characterized negative ?13CVPDB values (reaching ?10.67‰), involved evaporated seawater deposited sediments, mixed input freshwater. second stage mixture meteoric water hot precipitated as late cements. have higher depleted O–C compositions compared seawater. display positive covariance associated extra- ?18OVPDB (?12.87‰ ?0.82‰ for ?11.66‰ ?1.40‰ respectively). distinction between secondary also evident 87Sr/86Sr host limestone versus limestones up 0.72859, indicative riverine input, while (0.70772), fluid circulation interacting during diagenesis.