The Iberian Basin was an intracratonic rift basin in central-eastern Spain developed since Early Permian times. The basin boundary faults were normal, listric faults controlling an asymmetric extension propagating northeast with time.Hercynian or older lineaments controlled the orientation of the Iberian Basin and extension was accommodated basically in the hanging wall block by the formation of secondary grabens and a central high. The basin was related with the coeval Ebro, Catalan and Cuenca-Mancha Basins and their connections are discussed.Subsidence curves show that the Early Permian-Early Jurassic period of extension can be subdivided into three rifting episodes and a flexural one. Extension factor increases from 1.17 in the northwest to 1.29 near the Mediterranean coast.The increasing extension rate was accommodated by transfer faults trending NNE-SSW, more important in the Levante area. The rift evolution is intermittent and seems to reflect distinct stress fields.The collapse of the late Hercynian orogen and related increased heat flux, extension and rifting is the most probable origin of the Iberian Basin and related basins. The origin of the Catalan and the Valencia-Prebetic Basins is related to the southwards migration of the Hesse-Burgundy Rift along the eastern margin of the Iberian Microplate.

The main aim of this paper is to review Middle Permian through Middle Triassic continental successions in European. Secondly, areas of Middle-Late Permian sedimentation, the Permian-Triassic Boundary (PIB) and the onset of Triassic sedimentation at the scale of the westernmost peri-Tethyan domain are defined in order to construct palaeogeographic maps of the area and to discuss the impact of tectonics, climate and sediment supply on the preservation of continental sediment.At the scale of the western European peri-Tethyan basins, the Upper Permian is characterised by a general progradational pattern from playa-lake or floodplain to fluvial environments. In the northern Variscan Belt domain, areas of sedimentation were either isolated or connected to the large basin, which was occupied by the Zechstein Sea. In the southern Variscan Belt, during the Late Permian, either isolated endoreic basins occurred, with palaeocurrent directions indicating local sources, or basins underwent erosion and/or there was no deposition. These basins were not connected with the Tethys Ocean, which could be explained by a high border formed by Corsica-Sardinia palaeorelief and even parts of the Kabilia microplate. The palaeoflora and sedimentary environments suggest warm and semi-arid climatic conditions. At the scale of the whole study area, an unconformity (more or less angular) is observed almost everywhere between deposits of the Upper Permian and Triassic, except in the central part of the Germanic Basin. The sedimentation gap is more developed in the southern area where, in some basins, Upper Pennian sediment does not occur. The large sedimentary supply, erosion and/or lack of deposition during the Late Permian, as well as the variable palaeocurrent direction pattern between the Middle-Late Permian and the EarlyTriassic indicate a period of relief rejuvenation during the Late Pennian. During the Induan, all the intra-belt basins were under erosion and sediment was only preserved in the extra-belt domains (the northern and extreme southern domains). In the northern domain (the central part of the Germanic Basin), sediment was preserved under the same climatic conditions as during the latest Permian, whereas in the extreme southern domain, it was probably preserved in the Tethys Ocean, implying a large amount of detrital components entering the marine waters. Mesozoic sedimentation began in the early Olenekian; the ephemeral fluvial systems indicate arid climatic conditions during this period.Three distinct areas of sedimentation occur: a northern and southern domain, separated by an intra-belt domain.The latter accumulated sediments during the Early-Middle Permian and experienced erosion and/or no-deposition conditions between the Middle-Late Pennian and the beginning of Mesozoic sedimentation, dated as Anisian to Hettangian. At the top of the Lower Triassic, another tectonically induced, more or less angular unconformity is observed: the Hardegsen unconformity, which is dated as intra-Spathian and is especially found in ...

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The Iberian Chain is a wide intraplate deformation zone formed by the tectonic inversion during the and basin evolution analysis, macrostructural Bouguer gravity anomaly analysis, detailed mapping and paleostress inversions have been used to prove the important role of strike slip deformation. In addition, we demonstrate that two main folding trends almost perpendicular (NE SW ID E W artd NW SE) were simultaneously active in a wide transpressive zone. The two fold trends were generated by different mechanical behaviour, induding buckling and bending under constrictive strain conditions. We propose that strain partitioning occurred with oblique compression and transpression during the Cenozoic.

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The Iberian Basin or its present-day expression, the Iberian Ranges, was refilled with red bed sediments of alluvial origin during the late Olenekian -Anisian period represented by the Cañizar (Olenekian -Anisian) and Eslida (Anisian) Formations, both commonly known as Buntsandstein facies. In the late part of the Anisian, the Tethys Sea reached the eastern side of the Iberian microplate, represented by the shallow marine facies of the Landete and Cañete Formations, also called Muschelkalk facies. The ichnites studied in this paper belong to the Anisian continental-marine transition in the SE Iberian Ranges.The Cañizar Formation shows the oldest Triassic footprints found in the Iberian Peninsula, consisting in swimming, uncomplete lacertoid three digit Rhynchosauroides traces with possibly resting (cubichnia) and furrowing (pascichnia) Cruziana/Rusophycus due to large triopsids. Specimens from Lacertoïd and Crocodiloïd groups have been collected in the Eslida Formation. Rhynchosauroides sp. is the most representative ichnospecies of the first group, while in the Crocodiloïd group, the presence of Chirotherium barthii Kaup 1835 and Isochirotherium cf coureli (Demathieu 1970) are distinctive. In the Landete Formation specimens are found from Crocodiloïd and Dinosauroïd groups. Brachychirotherium gallicum Willruth 1917, Brachychirotherium sp. and Chirotherium sp. are characteristic of the first one, and 'Coelurosaurichnus' perriauxi and cf Paratrisauropus latus as the most representative of the second group. Some of the specimens described here present ancestors in the Early Triassic and have been described in the Triassic of North America, Italy and France. Possible paleogeographical connections with faunas of SE France can be inferred.Based on different sedimentary structures and plant remains, the footprints are related to fluvial systems within huge flood plains, playa and shallow marine environments, with alternating dry and wet periods. The vertical ichnites distribution during the Anisian shows that the fauna modification was weak at a high clade level. In the Triassic of the Iberian microplate, there are no findings of traces prior to the Anisian, and the footprint content for the Middle Triassic is less diversified than in other neighbouring regions. By comparison with other western Pangea areas, there was a later appearance of the forms after the end-Permian mass extinction event in the studied area.

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