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Original Article |
1 Área de Geodinámica Interna, Departamento de Ciencias de la Tierra, Universidad de Zaragoza, C/ Pedro Cerbuna, 12, E-50009, Zaragoza, Spain (e-mail: carluis@unizar.es)
2 Área de Estratigrafía, Departamento de Ciencias de la Tierra, Universidad de Zaragoza, C/ Pedro Cerbuna, 12, E-50009, Zaragoza, Spain
3 Departamento de Estratigrafía, Universidad Complutense, E-28040, Madrid, Spain
In the Galve sub-basin, the sedimentary record of the Upper HauterivianLower Barremian El Castellar Formation is divided into two stages by a marlstone interval with gypsum. Stage 1 shows a great variety of subenvironments and facies (alluvial, palustrine and lacustrine) whereas in stage 2 an extensive, shallow carbonate lake developed. Sedimentation was controlled by a system of south-dipping, ENEWSW listric normal faults, laterally bounded by NNWSSE steeper transfer faults. Faults controlled sedimentation from a basin scale (basin margins and main characteristics and evolution of sediments) to a regional and a local scale (thickness and facies distribution of the synrift series as well as the location and evolution of lakes and minor alluvial fans). The changes between stages 1 and 2 are related to the passing from an independent movement of faults to the movement of all the extensional faults as a whole, at a sole detachment level. The interval with gypsum was caused by underground water flow changes associated with the interrelation and connection of the faults in the transition period. These changes have been correlated with the transition from the rift initial stage to the rift climax stage, which took place in the HauterivianBarremian transition.