Echographic factors of atrial arrhythmia in patients with arrythmogenic right ventricular dysplasia

International audienceno abstrac

Répartition des minéraux argileux et contrôle tectono-eustatique dans les bassins de la marge tunisienneClay mineralogical distribution and tectono-eustatic control in the Tunisian margin basins

9 pages, 2 figures.L'étude minéralogique des argiles de la série stratigraphique du Paléozoïque au Néogène à travers les bassins sédimentaires de la marge tunisienne a été réalisée dans différents domaines paléogéographiques. Ce travail a pour objectif de percevoir la relation entre la répartition des argiles dans le temps et dans l'espace et les événements géodynamiques et eustatiques. Les cortèges argileux contemporains des régressions marines, accompagnées d'une intensification de l'érosion, sont ainsi à prédominance d'illite, alors que ceux relatifs aux transgressions suivies de climat chaud et sec sont accompagnés de smectite. Le minimum de niveau marin coïncide avec l'abondance de palygorskite. On tentera de relier les variations observées dans la nature et la teneur des minéraux argileux aux événements tectoniques de soulèvement et d'érosion et à ceux de rifting et de subsidence.Nos remerciements vont à H. Chamley, qui nous a permis d'améliorer notre texte, grâce à des critiques très pertinentes.Peer reviewe

Effects of sand addition on production of lightweight aggregates from Tunisian smectite-rich clayey rocks

10 pages, 7 figures, 3 tables.Smectite-rich claystone–marlstone samples from 12 outcrops located in the Southern Atlas domain of Tunisia were investigated with regard to manufacture of lightweight aggregates (LWAs). The clayey materials mainly consist of smectite, kaolinite and illite, together with quartz, calcite, dolomite and feldspars as accessory components. 10–12 mm pellets were prepared from wet paste and initially heated to 600 °C, 700 °C or 800 °C (depending on the raw material) for at least 2 h in order to avoid any explosion of the aggregate. The pellets were then subjected to a quick firing process at 1180 °C. The addition of 15% of quartz sand (< 250 μm grain size) to the raw materials was found to improve some required pre-treatments and give better expansion properties to some of the aggregates. The addition of 1% used automobile oil to the clay and quartz sand mixtures caused the formation of more gas and a drop in bloating temperature. The obtained LWAs were characterized by physical properties such as apparent density, mechanical resistance, water absorption and expansion. The laboratory results were comparable to those of two commercial LWAs from France (Argidécor®) and Portugal (LECA®) and provide new openings for the utilization of Tunisian claystone in civil engineering work or in agricultural applications.Peer reviewe

Effect of sand addition on production of lightweight aggregates from Tunisian smectiterich clayey rocks

Abstract Smectite-rich claystone-marlstone samples from 12 outcrops located in the Southern Atlas domain of Tunisia were investigated with regard to manufacture of lightweight aggregates (LWAs). The clayey materials mainly consist of smectite, kaolinite and illite, together with quartz, calcite, dolomite and feldspars as accessory components. 10-12 mm pellets were prepared from wet paste and initially heated to 600°C, 700°C or 800°C (depending on the raw material) for at least 2 h in order to avoid any explosion of the aggregate. The pellets were then subjected to a quick firing process at 1180°C. The addition of 15% of quartz sand (b 250 μm grain size) to the raw materials was found to improve some required pre-treatments and give better expansion properties to some of the aggregates. The addition of 1% used automobile oil to the clay and quartz sand mixtures caused the formation of more gas and a drop in bloating temperature. The obtained LWAs were characterized by physical properties such as apparent density, mechanical resistance, water absorption and expansion. The laboratory results were comparable to those of two commercial LWAs from France (Argidécor®) and Portugal (LECA®) and provide new openings for the utilization of Tunisian claystone in civil engineering work or in agricultural applications

Active Faulting Geometry and Stress Pattern Near Complex Strike‐Slip Systems Along the Maghreb Region: Constraints on Active Convergence in the Western Mediterranean

International audienc