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This work presents a 3D geometric model of growth strata cropping out in a fault-propagation fold associated with the Crevillente Fault (Abanilla-Alicante sector) from the Bajo Segura Basin (eastern Betic Cordillera, southern Spain). The analysis of this 3D model enables us to unravel the along-strike and along-section variations of the growth strata, providing constraints to assess the fold development, and hence, the fault kinematic evolution in space and time. We postulate that the observed along-strike dip variations are related to lateral variation in fault displacement. Along-section variations of the progressive unconformity opening angles indicate greater fault slip in the upper Tortonian–Messinian time span; from the Messinian on, quantitative analysis of the unconformity indicate a constant or lower tectonic activity of the Crevillente Fault (Abanilla-Alicante sector); the minor abundance of striated pebbles in the Pliocene-Quaternary units could be interpreted as a decrease in the stress magnitude and consequently in the tectonic activity of the fault. At a regional scale, comparison of the growth successions cropping out in the northern and southern limits of the Bajo Segura Basin points to a southward migration of deformation in the basin. This means that the Bajo Segura Fault became active after the Crevillente Fault (Abanilla-Alicante sector), for which activity on the latter was probably decreasing according to our data. Consequently, we propose that the seismic hazard at the northern limit of the Bajo Segura Basin should be lower than at the southern limit. This study was supported by: Spanish Ministry of Economy and Competitiveness (Research Project: CGL2011-30153-C02-02), Alicante University (Research Project: VIGROB053).

A litho-biostratigraphic analysis has been carried out in the Gador-Turon unit of the Sierra de Gador (Alpujarride complex, Betic Cordillera, SE Spain). The Triassic succession of this unit is composed of a lower meta-detrital formation overlain by an upper meta-carbonate formation divided in six members. In the latter, a Ladinian–Carnian-rich fossil association has been found (foraminifers, algae, bivalves, microproblematica, trace fossils). Facies analysis has enabled the recognition of 22 facies of platform origin. This succession accumulated as a subsiding margin-type carbonate platform with homoclinal ramp geometry (Anisian?–Ladinian) evolving into a fault-block-type platform with a steeper-margined geometry (Ladinian–Carnian). Slope deposits of this latter platform show a prism-like geometry with progradational patterns and include syn-sedimentary structures associated with normal faults capped by younger beds. The results of the present research indicate that the architecture of the platform studied has been controlled mainly by climate and oceanic factors during the development of the ramp, and by syn-sedimentary extensional tectonics during the development of the steeper-margined platform. The Ladinian–Carnian tectonic activity was probably also responsible for the siliciclastic input and the shift to a mixed terrigenous-carbonate platform.