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This paper describes the petrography and infers the provenance of siliciclastic rocks from the Upper Devonian of the Iberian Chains (Tabuenca, NE Spain), and outlines the tectonic setting associated with the Ebro Massif. These Devonian deposits are constituted by four different siliciclastic units: the Rodanas, Bolloncillos, Hoya and Huechaseca Formations. The provenance and diagenesis of over 400 sedimentary rocks samples are studied with a combination of petrographic polarizing microscope, scanning electron microscopy, atomic absorption spectroscopy, X-ray fluorescence and X-ray diffraction. In this sense, AAS and XRF analysis were used to determine the content of Ca, Mg, Fe, Mn, Na, K and Sr, among others; and XRD analysis was used to determine the clay's crystalline phases. These rocks experienced intense compaction and quartz cementation processes after deposition. No primary porosity remains nowadays and secondary porosity is rare. The formation of these siliciclastic rocks occurred mainly under subtropical climatic conditions, given the paleogeographical position of the current Iberian landmass during the Devonian.
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