References of "Fagel, Nathalie"
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See detailIdentification of the main parameters controlling the plasticity of ceramic pastes: The case study of the Marrakech region (Morocco)
El Boudour El Idrissi, Hicham ULg; Daoudi, Lahcen; Fontaine, François ULg et al

Poster (2015, July)

Numerous traditional ceramic workshops occur within a range of 10 to 80 km around the city of Marrakech. Our study aims to identify the main parameters controlling the plasticity of pastes used by the ... [more ▼]

Numerous traditional ceramic workshops occur within a range of 10 to 80 km around the city of Marrakech. Our study aims to identify the main parameters controlling the plasticity of pastes used by the artisans. To reach this goal, we characterize by X-ray diffraction, granulometry and plasticity index (PI) the local raw clayey material. <br />The investigation of 26 whole pastes shows the dominance of quartz (20 to 50%) and clay minerals (25 to 60%) with K-feldspar (2 to 17%), plagioclase (2 to 25%), calcite (0 to 18%), dolomite (0 to 15%), goethite (0 to7%) and trace of hematite and anhydrite (< 3%). Amphibole occurs in trace (< 5%) but only in some samples. The clay minerals are diversified, including illite (10 to 40%), kaolinite (2 to 15%), mixed-layer (ML) (0 to 10%), smectite, vermiculite and chlorite (0 to 5%), and pyrophyllite-talc association (0 to 8%). Sepiolite (12%) is only present in one paste. The grain size is made by variable proportions of sand (5 to 65%), silt (12 to 53%) and clayey fraction (18 to 66%). <br />The Plasticity index (PI) indicates the presence of two principals groups of pastes. <br />(1) The first group is characterized by PI values ranging between 15 to 18. Their moderate plasticity behavior is related either to the low rate of clayey fraction and/or to the absence of plastic clays like smectites and mixed layer with smectitic sheets. <br />(2) The PI of second group ranges between 20 to 32. The high plasticity values are influenced by the presence of specific clayey minerals like talc-pyrophyllite or sepiolite, or by the high content of smectite plus smectitic mixed-layers within the clayey (< 2 micron) fraction. Only one sample without any of these plastic minerals but with a high content of clayey fraction is characterized by a high PI value (24). <br />We concluded that the workability of ceramic paste in Marrakech region is controlled by a combination of factors, dominated by the grain size distribution and the content in plastic clay minerals within the fine fraction. [less ▲]

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See detailLand erosion and associated evolution of clay minerals assemblages in Mediterranean region (Southern Turkey): Amik Lake
El Ouahabi, Meriam ULg; Hubert, Aurelia ULg; Lebeau, Helene et al

Poster (2015, July)

Under Mediterranean context, continuous human occupation is attested in the Amik Basin (southern Turkey) since 6000-7000 BC. The Basin also is crossed by The Dead Sea Fault (DSF), a major neotectonic ... [more ▼]

Under Mediterranean context, continuous human occupation is attested in the Amik Basin (southern Turkey) since 6000-7000 BC. The Basin also is crossed by The Dead Sea Fault (DSF), a major neotectonic structure in the Middle East extending from the Red Sea in the south to the East Anatolian Fault Zone in the north. The study focuses on the mineralogy and clay mineralogy record of the Amik Lake occupying the central part of the Basin. Our objective is to constrain major mineralogical and clay minerals evolution in the area over the last 4000 years and assess changes that would be related to the different land uses during the different Bronze, Roman, Ottoman and Modern civilizations. Sediments were collected at 1 to 2 cm intervals in core sediments up to a depth of 6 meters in the clay deposits. Geochemistry (XRF), mineralogy (XRD) and clay mineralogy are applied to study the sediment records. The age of the record is constrained combining radionuclide and radiocarbon dating. Chemical and mineralogical composition of sediments is quite diversified reflecting the significant geological variation of drainage basins. Abundant mixed-layer and partly disordered minerals characterize the different sedimentary levels recorded in those cores. Levels relatively rich in chlorite, illite and quartz are interpreted as corresponding to relatively dry periods, while more humid periods lead to more intensive weathering and consequently to the dominance of clay minerals more advanced in the relative stability scale, such as kaolinite. Smectite is taken to indicate a climate with contrasting seasons and a pronounced dry season. The sedimentary record clearly shows two periods indicating strong soil erosion in the Lake catchment. The most recent erosion phase is modern. The oldest one would have started during the late Bronze period and lasted until the late Roman Period. The first and older period is attributed to a strong aggradation linked to major increase in erosion. Our study shows that this episode has specific characteristics: mixed-layer clay mineral, high percent in Ni, Cr and Mg coupled with significant amount of organic matter of terrestrial origin. Ni and Mg most probably come from the Amanos Mountains an ophiolitic belt indicating an intensive upland cultivation and possible exploitation of its mineral resource. The second period is attributed to the modern period. The signature of the increase in erosion is different, because most of the soil cover has already been eroded. Only a patchy thin and unmature soil cover exists since the Late Roman time. Erosion is associated with a marked increase of smectite-illite interstratified clay, goethite and hematite found in deep soil horizons. Moreover, a marked increase in Cr is showed and is probably related to an enhanced exploitation of its mineral resource and to a renew land exploitation of the Amanos Mountain Range. [less ▲]

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See detailLANDSLIDES IN CENTRAL AFRICA: FROM DEFORMATION MECHANISMS TO EVOLUTION PROCESSES – CASES STUDIES FROM RWANDA AND BURUNDI
Draidia, Salah ULg; Ndahimana, Hamuli; Habimana, Christophe et al

Scientific conference (2015, July)

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See detailThe influence of lithology on the mechanical strength and porosity of terra-cotta, the case study of Marrakech region (Morocco).
El Boudour El Idrissi, Hicham ULg; Daoudi, Lahcen; Collin, Frédéric ULg et al

Poster (2015, May 19)

The ceramic pastes in Marrakech region are prepared on the base of six types of raw materials of different lithologies. Various products are manufactured. The production consists of cooking utensils ... [more ▼]

The ceramic pastes in Marrakech region are prepared on the base of six types of raw materials of different lithologies. Various products are manufactured. The production consists of cooking utensils (based on schist, colluviums, quartzose sand and silt), decoration products (based on argillite, washing residues and soil), vases and gourds products (based on schist and soil), tiles (based on silt decantation) and traditional dishes (based on soil and argillite). In this study we elaborate bricks from the different raw material and we evaluate some of their physical properties after firing at 1050°C. In particular we measure the porosity to water and the mechanical strength of all the fired bricks. The aim is to compare the final product quality according to the origin (lithology) of the clayey raw material of the ceramic pastes. Based on our experiments, the bricks of the lower compressive strength (CS) and of the lower flexural strength (FS) are those based on sand (CS = 39 MPa; FS = 7 MPa), on silt decantation (CS = 25 to 39 MPa; FS = 10 to 18 MPa), and on schist and colluviums (CS = 20 to 51 MPa; FS = 6 to 17 MPa). Those of the highest values are based on argillites (CS = 33 to 102 MPa; FS = 13 to 28 MPa). The other pastes are characterized by intermediate values. The porosity ranges between 5 to 27%. The bricks based on silt decantation have the greatest values (20 to 27%), whereas those based on argillite have the lower values (5 to 10%). Those physical properties are, in most cases, in agreement with the requested values of the bricks industry. We conclude that such raw materials have high perspective to manufacture structural products of high performance in mechanical strength and thermal insulation. [less ▲]

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See detailGeoarchaeology of the ancient city of Utica (Tunisia) and evolution of the palaeoenvironment of the Medjerda delta
Pleuger, Elisa ULg; Abichou, Hakim; Gadhoum, Ahmed et al

Poster (2015, May)

Phoenician Utica remains today largely unknown, as is its role in the Phoenician expansion in the western Mediterranean. Aristotle and Pliny the Elder mention Utica as a maritime and port city and ... [more ▼]

Phoenician Utica remains today largely unknown, as is its role in the Phoenician expansion in the western Mediterranean. Aristotle and Pliny the Elder mention Utica as a maritime and port city and estimate its origin around the 11th c. BC. However, in the present state of research, no archaeological evidence is earlier than the 9th c. BC, and the location of the Phoenician and Roman port infrastructures remains unknown. Today, the ancient city is located on a promontory in the heart of the Medjerda delta, 10 km inland. This project proposes an interdisciplinary effort to understand the Medjerda delta landscape changes during the Holocene. It starts from an archaeological problem and proposes the contribution of geoarchaeology to the understanding of the relationship between ancient societies and their environment. The fluvial palaeoenvironments and sedimentary processes are studied through the mechanical extraction of cores (15-20 m deep) to reach the early Holocene. Selected sediment samples are then studied in laboratory, using different and complementary approaches. The location of port infrastructures will bring initial answers to the question of the foundation of the city. The study of river palaeoenvironments of the Medjerda delta during the Holocene aim at a better understanding of the nature of the settlement, as well as the function of the city of Utica over time. This study will also assess the impact of the ancient city on the environment and understand how the city adapted to the mobility of this Mediterranean delta. Furthermore, the analysis of sedimentary processes causing the filling of the harbour basin will lead to speculation about the causes of the abandonment of the structures and more generally the decline of the city in favor of Carthage. It will also examine whether natural or anthropogenic factors have influenced this deltaic progradation over the centuries. [less ▲]

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See detailHolocene palaoenvironmental records in PN speleothem (Han-sur-Lesse cave, southern Belgium
Allan, Mohammed ULg; Fagel, Nathalie ULg; Verheyden, Sophie

Conference (2015, April 16)

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See detailLead concentrations and isotope ratios in speleothems as proxies for atmospheric metal pollution since the Industrial Revolution
Allan, Mohammed ULg; Fagel, Nathalie ULg; Van Rampelbergh, Maïte et al

in Chemical Geology (2015)

Lead concentrations and isotope ratios from two speleothems from the Han-sur-Lesse cave in southern Belgium were measured in order to study the ability of speleothems to act as archives of atmospheric ... [more ▼]

Lead concentrations and isotope ratios from two speleothems from the Han-sur-Lesse cave in southern Belgium were measured in order to study the ability of speleothems to act as archives of atmospheric pollution. To address this aim we analyzed trace elemental Al and Pb compositions by LA-ICP-MS and ICP-MS as well as Pb isotopes by MC-ICP-MS. The results help to identify three intervals characterized by particularly high enrichment of Pb: from 1880 to 1905 AD, from 1945 to 1965 AD, and from 1975 to 1990 AD. The speleothem record shows similar changes as the known historical atmospheric pollution level in Belgium. Lead isotope ratios discriminate between Pb sources and confirm that coal and gasoline combustion, combined with regional metallurgical activities, were the predominant Pb pollution sources in the stalagmites during the last 250 years. This study opens possibilities to determine anthropogenic versus natural metal sources in well-dated speleothem archives. [less ▲]

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See detailMineralogical and physico-chemical characteristics of Cameroonian smectitic clays after treatment with weakly sulfuric acid
Mache, Jacques Richard; Signing, P.; Mbey, J.A. et al

in Clay Minerals (2015), 50

Smectitic clays from the Sabga and Bana areas, western Cameroon were treated with sulfuric-acid solutions of various concentrations – 0.5, 0.7, 1.0 and 4.0 N – at 80°C for 2 h. The mineralogical ... [more ▼]

Smectitic clays from the Sabga and Bana areas, western Cameroon were treated with sulfuric-acid solutions of various concentrations – 0.5, 0.7, 1.0 and 4.0 N – at 80°C for 2 h. The mineralogical, physicochemical and morphological characteristics of the samples treated were analysed using several techniques. The sulfuric acid caused structural modification of the dioctahedral smectite. The accessory minerals such as cristobalite, quartz, feldspars and anatase remained unaltered by the acid attack. The supernatant solutions after acid treatment contain Mg, Ca, K, Na, Si, Al and Fe as a result of partial dissolution of octahedral and tetrahedral cations. The activated clay samples exhibited a smaller cation exchange capacity (CEC) and the specific surface area (SSA) increased with increasing concentration of sulfuric acid, ranging from 65 to 134 m2/g for the sample from Bana and from 74 to 84 m2/g for the sample from Sabga. The different SSA values were affected by the relative abundance of smectite and cristobalite (SiO2/Al2O3 = 2.2 and 6.5, respectively, from Bana and Sabga). The activated clays from Bana and Sabga displayed interesting physicochemical and textural properties and can be considered as promising adsorbents for the bleaching of vegetable oils. [less ▲]

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See detailSedimentary records of past earthquakes in Boraboy Lake during the last ca 600 years (North Anatolian Fault, Turkey).
Avsar, Ulas; Hubert, Aurélia ULg; De Batist, Marc et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (2015), (433), 1-9

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See detailOccurences of kaolin in Koutaba (west Cameroon): Mineralogical and physicochemical characterization for use in ceramic products
Nkalih Mefire, Abiba ULg; Njoya, A.; Yongue Fouateu, R. et al

in Clay Minerals (2015), 50(5), 593-606

Thirty clay samples collected from three hills in Koutaba (west Cameroon) were characterized in order to evaluate their potential use as raw materials for ceramics. After preliminary mineralogical ... [more ▼]

Thirty clay samples collected from three hills in Koutaba (west Cameroon) were characterized in order to evaluate their potential use as raw materials for ceramics. After preliminary mineralogical identification by X-ray diffraction, three representative samples from the three different hills, referred to hereafter as K1M, K2M and K3M, were selected for further investigation by X-ray fluorescence, plasticity, granularity and thermogravimetric analysis. The main clay minerals are kaolinite (32–51%) and illite (up to 12%). Additional major phases are quartz (32–52%), goethite (6–7%) and feldspars (0–4%). The chemical composition showed variable amounts of SiO2 (60–72%), Al2O3(15–20%) and Fe2O3 (1–9%), in accordance with the quartz abundance in all of the samples studied. The particle-size distribution showed a large proportion of silty fraction (64–88%) with moderate sandy (9–19%) and clayey fractions ( < 5% for K2M, 12% for K1M and 20% for K3M). All of the clays showed moderate plasticity-index values (8–11%). Because of these characteristics, K1M and K3M may be suitable for use in common bricks and hollow ceramic products. Sieving or the addition of ball clays is recommended to increase the plasticity of sample K2M for use in common bricks. [less ▲]

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See detailRole of the texture of fibrous clay minerals in the plasticity behavior of host materials (Plateau du Kik, Western High Atlas, Morocco)
Daoudi, L.; Knidiri, Abdelouahab; El Boudour El Idrissi, Hicham ULg et al

in Applied Clay Sciences (2015), 118

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See detailTerritoires périurbains : développement, enjeux et perspectives dans les pays du Sud. Une introduction générale
Halleux, Jean-Marie ULg; Courtejoie, Fabienne ULg; Dawance, Sophie ULg et al

in Bogaert, Jan; Halleux, Jean-Marie (Eds.) Territoires périurbains Développement, enjeux et perspectives dans les pays du Sud (2015)

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See detailEnvironmental and Climatic Changes during the Pleistocene-Holocene in the Bor Plain, Central Anatolia, Turkey
Altin, T.; El Ouahabi, Meriam ULg; Fagel, Nathalie ULg

in Palaeogeography, Palaeoclimatology, Palaeoecology (2015)

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See detailEnvironmental significance of Upper Miocene phosphorites at hominid sites in the Lukeino Formation (Tugen Hills, Kenya)
Dericquebourg, Perrine ULg; Person, Alain; Ségalen, Loïc et al

in Sedimentary Geology (2015), 327

The Lukeino Formation contains an important sedimentary and fossiliferous record of the late Miocene (6.09–5.68 Ma), which has in particular yielded the fossil remains of the oldest East African bipedal ... [more ▼]

The Lukeino Formation contains an important sedimentary and fossiliferous record of the late Miocene (6.09–5.68 Ma), which has in particular yielded the fossil remains of the oldest East African bipedal hominid called Orrorin tugenensis. This fluvio-lacustrine sedimentary succession crops out in the Kenyan part of the East African Rift. It is mainly composed of clay to sandy clay deposits intercalated with volcanic ash horizons, and localized layers of carbonates and diatomites. A detailed sedimentological and mineralogical study of the Lukeino Formation was conducted to throw light on the environmental conditions in which the hominids lived. Several centimetric, relatively continuous and indurated phosphatic horizons, of sedimentary origin, were identified at two sites (Sunbarua and Kapcheberek). Mineralogical (XRD) and geochemical analyses as well as observations by SEM, which was coupled with an energy dispersive spectroscopy (EDS) microprobe, indicate that the autochthonous phosphate layers are composed of a micritic matrix of francolite (38–93%), with incorporation of silicates in variable proportions from one layer to another. The phosphate matrix contains very well preserved and abundant diatom frustules in the basal phosphate layer. These diatoms are identified as Aulacoseira granulata, implying a pH of 7.8–8.2 for freshwaters of the Palaeolake Lukeino. Calcitic tubular structures, linked to a possible bacterial origin, are also observed locally. Phosphate layers occur abruptly within a thick clay–sandy series, associated with an intense runoff phase during the deposition of this interval of the Lukeino Formation. The massive and cyclic input of phosphorus to the lake promoted productivity to the stage where it caused a diatom bloom. The establishment of several phosphate horizons testifies to successive phases of eutrophication of Palaeolake Lukeino. The diatom cells provided some of the organic matter, which was decomposed by bacterial activity at the bottom of the lake in suboxic conditions, but in insufficient quantities to fully form the phosphatic materials. The rest of the organic matter needed for phosphogenesis came from terrigenous supply (plant debris), suggesting the presence of dense vegetation in the catchment of the Palaeolake Lukeino, during this well-drained interval of deposition of the Lukeino Formation. [less ▲]

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See detailCaractérisation de colluvions triasiques utilisés dans l'élaboration d'ustensiles rustiques de cuisson, cas de Talatast (Région de Marrakech, Maroc)
El Boudour El Idrissi, Hicham ULg; Daoudi, Lahcen; Collin, Frédéric ULg et al

in Verres, Céramiques & Composites (2014), 3(2), 18-22

The raw material used in the potter site of Talatast (Morocco) is collected from Triassic colluviums. Our study aims to characterize the mineralogical and geotechnical properties of the local clayey ... [more ▼]

The raw material used in the potter site of Talatast (Morocco) is collected from Triassic colluviums. Our study aims to characterize the mineralogical and geotechnical properties of the local clayey material before and after cooking. Our results confirm that the coarse particle size, the mineralogy of the clay fraction and the rate of fondants are suitable for the cookware material production. Defects encountered during the production are mainly related to the use of traditional ovens. Understanding the origin of the main defects could be helpful to promote the local pottery production. [less ▲]

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See detailCharacteristics and ceramic properties of clayey materials from Amezmiz region (Western High Atlas, Morocco)
Daoudi, Lahcen; El Boudour El Idrissi, Hicham ULg; Saadi, Latifa et al

in Applied Clay Science (2014)

Five clayey materials from two quarries located in the Amezmiz region (Morocco) were sampled and investigated for their physical, chemical, mineralogical and thermal characteristics to evaluate their ... [more ▼]

Five clayey materials from two quarries located in the Amezmiz region (Morocco) were sampled and investigated for their physical, chemical, mineralogical and thermal characteristics to evaluate their potential suitability as raw materials in various ceramic applications. Physical properties were identified by particle size distribution, consistency limits and total organic content. Chemical, mineralogical, and thermal properties were investigated by XRF, XRD, and TG/DTA techniques, respectively. A common raw material in pottery manufacturing of Morocco was used as reference sample (REF). Results show that the main oxides in the samples were SiO2, Al2O3, and Fe2O3, whereas the other oxides were present only in small quantities. Quartz, illite and vermiculite were present as dominant mineral phases with minor kaolinite, calcite and smectite. The results showed that three of the studied clayey materials have adequate characteristics for the production of structural ceramics. However, for the two other clays it is necessary to add more plastic clays to enhance the workability. [less ▲]

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See detailIndice de Kaolin à Koutaba (Ouest - Cameroun):
Nkalih Mefire, Abiba ULg; NJOYA, André; Mache, Jacques-Richard et al

Conference (2014, October 28)

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See detailRecyclage des briques cassées pour améliorer les propriétés céramiques des argiles plastiques (Meknès, Maroc)
El Ouahabi, Meriam ULg; Daoudi, Lahcen; El Boudour El Idrissi, Hicham ULg et al

Poster (2014, October 27)

Dans le Bassin de Saïs (nord ouest du Maroc), les argiles du Miocène de la région de Meknès sont utilisées dans l’industrie céramique locale pour la fabrication des briques. Ces argiles riches en smectite ... [more ▼]

Dans le Bassin de Saïs (nord ouest du Maroc), les argiles du Miocène de la région de Meknès sont utilisées dans l’industrie céramique locale pour la fabrication des briques. Ces argiles riches en smectite et en carbonates, ont une granulométrie très fine, marquée par la quasi absence de la fraction sableuse. Ces propriétés les rendent très plastiques, ce qui engendre des taux de retrait importants au séchage et à la cuisson et des problèmes de qualité du produit fini qui s’en suivent (fissurations, déformations et casses pendant les processus de séchage et de cuisson). Dans le but de palier à ce problème et d’améliorer la qualité du produit fini, nous proposons au cours de cette étude de recycler les déchets de briques cassées. Afin d'atteindre ces objectifs, 4 formulations ont été réalisées à base d’argiles plastiques, riches en smectite et des casses de briques broyées. Des quantités de 5, 10, 15 et 20% de briques broyées ont été ajoutées à la pâte destinée à la confection des briques. Des analyses minéralogiques par diffraction des rayons X (DRX), chimiques par spectrométrie de fluorescence (XRF), granulométrique par granulométrie laser, ainsi que les limites d’Atterberg ont été effectuées. Les résultats minéralogiques montrent une diminution de la teneur en carbonates (calcite) et en argile totale (principalement smectite), lors des ajouts successifs de briques broyées. La fraction sableuse augmente progressivement, jusqu’à atteindre 30% pour une formulation avec 20% de casses de briques. Cette granulométrie plus grossière diminue la plasticité de la pâte et permet d’éviter les déformations et les fissures pendant le processus du séchage. De plus, l’ajout des casses de briques dilue les carbonates, ce qui permet d’améliorer la qualité du produit cuit. Ces résultats indiquent que le recyclage des déchets de briques, présente un intérêt à la fois économique et écologique. Des essais de comportement au séchage et à la cuisson ainsi que des essais mécaniques complèteront cette étude. [less ▲]

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See detailUtilisation des résidus de lavage des granulats de carrières dans l'élaborationde pièces céramiques (Région de Tamazouzt, Maroc)
El Boudour El Idrissi, Hicham ULg; Daoudi, Lahcen; El Ouahabi, Meriam ULg et al

Conference (2014, October)

Le site potier de Tamazouzt est situé à 40 km au Sud-Est de la ville de Marrakech. La production est sous forme de poterie décorative d’ustensiles rustiques. La matière première utilisée dans ... [more ▼]

Le site potier de Tamazouzt est situé à 40 km au Sud-Est de la ville de Marrakech. La production est sous forme de poterie décorative d’ustensiles rustiques. La matière première utilisée dans l’élaboration de ces produits est issue de résidus de lavage des carrières de granulats exploités le long des oueds. En plus de la qualité des produits et des rendements élevés, ce site donne un bon exemple de valorisation des résidus de lavage qui causent des problèmes pour l’environnement et pour les industriels. Nous avons caractérisé cette matière première afin d’en faire la promotion et d’encourager l’exploitation de tels matériaux dans le domaine de la céramique à l’échelle globale. Les résultats des analyses montrent que la pâte est constituée de 62% d’argiles, 23% de limons et 15% de sables ; l’indice de plasticité est de l’ordre de 16. Pour 27% d’humidité, le degré de retrait au séchage ne dépasse pas 6%. La minéralogie indique la présence de quartz (32%), plagioclase (20%), feldspaths potassiques (10%), calcite (3%) et argile (31%). Les minéraux argileux sont constitués d’illite (16%), de chlorite (7%), de kaolinite (4%) et de vermiculite (4%). La teneur en matière organique est de 4%. La composition chimique est surtout silico-alumineuse (64% de SiO2, 17% d’Al2O3). Les autres éléments majeurs dont la teneur est significative (> 1%) sont : Fe2O3 (8%), MgO (4%), K2O (3%), CaO (3%), Na2O (2%). Les pièces cuites à 1050°C présentent 2% de retrait, 13% de porosité à l’eau, la résistance mécanique à la compression et à la flexion est respectivement de 63 et 20 Mpa. L’analyse DRX des pièces cuites à 1050°C a montré l’apparition de géhlénite, anorthite, diopside et d’hématite. Ces résultats indiquent qu’en plus de l’utilisation locale dans la poterie décorative ces argiles pourraient être valorisées comme matériaux de construction vue leur caractère isolant (bonne porosité), résistance (bon comportement mécanique) et leur couleur rouge (présence de l’hématite). [less ▲]

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See detailHolocene evolution of the coastal system of Sfax (SE Tunisia)
Lamourou, Ali ULg; Touir, jamel; Fagel, Nathalie ULg

Poster (2014, July 07)

This study aims to identify the depositional environments along the Tunisian coastal system and to follow their evolution over the Holocene. The material consists in three marine sediment cores retrieved ... [more ▼]

This study aims to identify the depositional environments along the Tunisian coastal system and to follow their evolution over the Holocene. The material consists in three marine sediment cores retrieved at 3 meter depth from the Northern coastal system of Sfax («Société d'Étude et d'Aménagement des Côtes Nord de la Ville de Sfax", site TAPARURA). The identification of the different depositional paleoenvironments was mainly based on field campaigns and laboratory mineralogical and sedimentological analyses of sediments. The vertical succession analysis of depositional facies allows to identify 2 main environments. First a fluviatile depositional environment (coastal plain) is characterized by fluviatile channels facies and inundation plains at the bottom of the cores. Second, at the top of the cores, we observed a marine sandy sedimentation with numerous bioclasts of gasteropods, lamellibranches and algae. This facies evolution is consistent with a relative sea level rise, responsible for the flooding of the fluviatile system at the level of the coastal plain. The main factor controlling the facies evolution and the sediment thickness variation is the local sea-floor morphology. The Holocene seabed is mainly inherited from the last glacial maximum morphology. Resulting from an important fluviatile digging that occurred, the relative sea-level fluctuations, the hydro-isostatic rebound and the climate. [less ▲]

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