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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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Abstract. The topographic evolution of continents and especially the growth and dismembering of mountain ranges plays a major role in the tectonic evolution of orogenic systems, as well as in regional or global climate changes. A large number of studies have concentrated on the description, quantification and dating of relief building in active mountain ranges. However, deciphering the topographic evolution of a continental area submitted to recurrent tectonic deformation over several hundred millions of years remains a challenge. Here we present a synthesis of the tectonic, geochronological and sedimentological data available on the intracontinental Tian Shan Range to describe its general topographic evolution from Late Palaeozoic to Early Tertiary. We show that this evolution has occurred in two very distinct geodynamic settings, initiating during the Carboniferous in an ocean subduction -continent collision tectonic context before becoming, from Early Permian, purely intra-continental. We show that during most of the Mesozoic, the topography is mostly characterized by a progressive general decrease of the relief. Nonetheless localized, recurrent deformation induced the formation of small-scale reliefs during that period. These deformations were driven by far field effects of possibly several geodynamic processes in a way that still remains to be fully understood.

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The topographical evolution of tectonic systems, as well as the sedimentation pattern and depositional environments in the associated basins, are controlled by both tectonics and climate. In the region of the Tien Shan (Central Asia), the Jurassic–Lower Cretaceous period was marked by complex, low-intensity tectonic deformation and major climate changes from humid to arid conditions (Jurassic) to semi-arid conditions (Cretaceous). Using the sediment record in the Junggar, Tarim and Fergana basins to describe the tectonic evolution of the Tien Shan area during the Mesozoic thus requires differentiation between the tectonic and climatic influences on sedimentation. The conglomerates of the Upper Jurassic–Lower Cretaceous Kalaza Formation were commonly associated with renewed tectonic activity resulting from the docking of the Lhasa block along the southern margin of Asia. From sedimentology and sequence stratigraphy analyses of several sections in the Junggar, Tarim and Fergana basins, we reassess the main factors controlling the deposition of this formation. We show that, while some tectonic activity persisted throughout the Jurassic–Cretaceous transition, the switch from the sandy deposits of the Upper Jurassic Qigu Formation to the coarse deposits of the Kalaza Formation is largely linked to the development of an arid climate

International audienceBased on a detailed sedimentological analysis of Lower Triassic continental deposits in the western Germanic sag Basin (i.e. the eastern part of the present-day Paris Basin: the 'Conglomérat basal', 'Grès vosgien' and 'Conglomérat principal' Formations), three main depositional environments were identified: (i) braided rivers in an arid alluvial plain with some preserved aeolian dunes and very few floodplain deposits; (ii) marginal erg (i.e. braided rivers, aeolian dunes and aeolian sand-sheets); and (iii) playa lake (an ephemeral lake environment with fluvial and aeolian sediments). Most of the time, aeolian deposits in arid environments that are dominated by fluvial systems are poorly preserved and particular attention should be paid to any sedimentological marker of aridity, such as wind-worn pebbles (ventifacts), sand-drift surfaces and aeolian sand-sheets. In such arid continental environments, stratigraphic surfaces of allocyclic origin correspond to bounding surfaces of regional extension. Elementary stratigraphic cycles, i.e. the genetic units, have been identified for the three main continental environments: the fluvial type, fluvial­aeolian type and fluvial/playa lake type. At the time scale of tens to hundreds of thousands of years, these high-frequency cycles of climatic origin are controlled either by the groundwater level in the basin or by the fluvial siliciclastic sediment input supplied from the highland. Lower Triassic deposits from the Germanic Basin are preserved mostly in endoreic basins. The central part of the basin is arid but the rivers are supplied with water by precipitation falling on the remnants of the Hercynian (Variscan)­Appalachian Mountains. Consequently, a detailed study of alluvial plain facies provides indications of local climatic conditions in the place of deposition, whereas fluvial systems only reflect climatic conditions of the upstream erosional catchments