Publications of Aurelia Hubert
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See detailA 3800 yr paleoseismic record (Lake Hazar sediments, eastern Turkey): Implications for the East Anatolian Fault seismic cycle
Hubert, Aurelia ULiege; Lamair, Laura ULiege; Hage, Sophie et al

in Earth and Planetary Science Letters (2020), 538

The East Anatolian Fault (EAF) in Turkey is a major active left-lateral strike-slip fault that was seismically active during the 19th century but mostly quiet during the 20th century. Geodetic data ... [more ▼]

The East Anatolian Fault (EAF) in Turkey is a major active left-lateral strike-slip fault that was seismically active during the 19th century but mostly quiet during the 20th century. Geodetic data suggests that the fault is creeping along its central part. Here we focus on its seismic history as recorded in the sediments of Lake Hazar in the central part of the EAF. Sediment cores were studied using X-ray imagery, magnetic susceptibility, grain-size, loss-on-ignition and X-ray fluorescence measurements. Recurring thin, coarse-grained sediment units identified as turbidites in all cores were deposited synchronously at two deep study sites. The turbidite ages are inferred combining radiocarbon and radionuclide (137Cs and 210Pb) dating in an Oxcal model. A mean recurrence interval of ~190 years is obtained over 3800 yrs. Ages of the recent turbidites correspond to historical earthquakes reported to have occurred along the EAF Zone or to paleoruptures documented in trenches just northeast of Lake Hazar. The turbidites are inferred to be earthquake-triggered. Our record demonstrates that Lake Hazar has been repeatedly subjected to significant seismic shaking over the past 3800 years. The seismic sources are variable: ~65% of all turbidites are associated with an EAF source. The seismic cycle of central EAF is thus only partly impacted by creep. [less ▲]

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See detailEntre pressions anthropiques et marines, l’érosion côtière autour de la ville de Kribi, Cameroun
Mbevo Fendoung, Philippes ULiege; Hubert, Aurelia ULiege

Conference (2019, September 20)

Dans sa vision à l’horizon 2035, le gouvernement camerounais entend construire son économie au rang des économies intermédiaires. Pour ce faire, il se concentre sur la construction d’infrastructures ... [more ▼]

Dans sa vision à l’horizon 2035, le gouvernement camerounais entend construire son économie au rang des économies intermédiaires. Pour ce faire, il se concentre sur la construction d’infrastructures majeures et Kribi joue un rôle central dans cette initiative avec notamment l’autoroute Kribi-Edéa et le port en eau profonde de Kribi. Comme pour toute structure de port maritime, la construction du port de Kribi en 2015 a eu un impact important sur le littoral et a entraîné une érosion côtière importante. La digue de protection du port a été construite sur la trajectoire de la dérive côtière, ce qui crée des situations d’aggradation en aval mais d’érosion côtière en amont. En outre, le développement de Kribi a donné lieu à l’extension des plantations agro-industrielles de SOCAPALM et HEVECAM. Tout cela contribue à l’affaiblissement de l’environnement côtier à la fragilité de son écologie. Une étude antérieure de Tchindjang et al. (2019) a déjà montré qu’il y avait des changements côtiers importants au Cameroun. Ils se produisent principalement à l’embouchure des grandes rivières (Lobé, Nyong et Ntem), mais aussi à des endroits où l’amplitude des marées et la vitesse des vagues sont importantes. Globalement, les zones de couverture côtière avancée entre 1973 et 2007 ont une superficie moyenne de 4 081 400 m2 représentant 45 % de la dynamique totale. En revanche, il existe une dynamique régressive correspondant au retrait linéaire côtier qui affecte principalement les secteurs concaves de la côte, composés principalement de roches ou de sédiments meubles. Entre 1973 et 2007, il s’agissait d’une surface moyenne de 4 949 550 m2 représentant 55 % de la dynamique totale. Le recul des côtes peut être amplifié et accéléré par les activités humaines, tout en constituant une menace pour les investissements et les constructions localisées sur le littoral et pour la biodiversité in situ, en dépit des travaux de protection qui peuvent y être construits. Le but de cette recherche est d’analyser la dynamique de la côte kribienne entre 2000 et 2019, de mettre en évidence les facteurs amplificateurs et de quantifier les zones d’accumulation et de recul des zones côtières. L’approche méthodologique articule deux approches: (i) une analyse par télédétection visant à étudier la dynamique de l’utilisation des sols et du littoral entre 2000 et 2019, à l’aide d’images satellite de type Lansdat et sentinelle. Les images ont une résolution spatiale qui varie de 10 à 15 m. Une analyse statistique de l’évolution de la démographie et des surfaces imperméabilisées. (ii) L’outil Digital Shorline Analysis System (DSAS) est utilisé pour modéliser la cinématique côtière. Comme prévu, le niveau de régression du littoral sera connu, ainsi que l’état de l’occupation du sol et ses implications sur la dynamique côtière. [less ▲]

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See detailAPPLICATION OF REMOTE SENSING AND GIS IN COASTAL EROSION MAPPING IN CAPE CAMEROON
Mbevo Fendoung, Philippes ULiege; Tchindjang, Mesmin; Hubert, Aurelia ULiege

Conference (2019, July 03)

Cape Cameroon is a small, insular territory bordering the northern shore of the Wouri estuary in Cameroon. It is located in the 6th district of the city of Douala (1 907 479 inhabitants (BUCREP, 2010 ... [more ▼]

Cape Cameroon is a small, insular territory bordering the northern shore of the Wouri estuary in Cameroon. It is located in the 6th district of the city of Douala (1 907 479 inhabitants (BUCREP, 2010)), with Manoka as its capital. It is occupied by 2654 inhabitants. This territory is occupied mainly by a Nigerian ethnic group, and the Cameroonian sovereignty has been fighting in this Cameroonian territory since the 1998-2008 conflict with Nigeria on the Bakassi peninsula.Coastal erosion is very intense and affects populations and ecosystems. Sustainable development is a particular challenge in this insular territory because the population is confronted with important coastal erosion phenomena and that cannot migrate inland because of the Mabé swamp Natural Reserve. Since the beginning of the 2000s, coastal erosion has removed houses, infrastructures and a large part of the Mabé Reserve. This contribution aims to mobilize remote sensing and GIS tools and data to (1) map the different sequences of the coastline retreat in Cape Cameroon and highlight the main factors, and (2) map the mangrove degradation due to the inland motion of the anthropic pressure, and (3) make projection for future of this territory. For modeling the coastal kinematics, the mapping is based on the Digital Shoreline Analysis System (DSAS) model, developed by Thieler et al. (2009). We used supervised classifications of Landsat images from the 1975, 1986, 2000 and 2018 with 30-meter resolution according to the maximum likelihood algorithm. We could thus assess the land use change and extract shorelines. Furthermore we use field observations, the testimonies of the people who lived for a long time along the shore to access if (1) erosion occurs continuously or during extreme events and if (2) mangrove degradation is linked to coastal erosion. Between 1986 and 2014, earth losses are estimated at more than 103 ha. Mangroves recorded a considerable degradation that the rate is estimate of 13.68%. The improved quantification of coastal erosion (in terms of soil area loss), the human occupation and land degradation through time and its possible future evolution allow to address the specific challenge of closed restricted territories occupied by growing poor and marginalized population, and the long-term sustainability of a natural reserve in such environment. [less ▲]

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See detailCosmogenic data about uplifted river terraces: implications regarding the central north anatolian fault segment and the central pontide orogenic wedge
Hubert, Aurelia ULiege; Drab, Laureen; Benedetti, Lucilla et al

Conference (2019, January 29)

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See detailQuestion about the seismic cycle of the East Anatolian Fault and its seismic versus aseismic behavior
Hubert, Aurelia ULiege; Lamair, Laura ULiege; Hage, Sophie et al

Conference (2019, January 29)

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See detailCOMBINING GEOLOGY, GEOMORPHOLOGY AND GEOTECHNICAL DATA FOR A SAFER URBAN EXTENSION: APPLICATION TO THE ANTANANARIVO CAPITAL CITY (MADAGASCAR)
ANDRIAMAMONJISOA, Solofo Nirina; Hubert, Aurelia ULiege

in Journal of African Earth Sciences (2019)

Metropolitan and suburban areas in Africa are rapidly expanding with, in general, a poor safe urban management. Urban development in zones not suitable for construction leads to significant economic loss ... [more ▼]

Metropolitan and suburban areas in Africa are rapidly expanding with, in general, a poor safe urban management. Urban development in zones not suitable for construction leads to significant economic loss. The aggregate building damage combined with other environmental treats like drought, flooding or landsliding are enhancing African city vulnerability. Simple cartographic products made available to the general public could facilitate the first stage of planning and management considering parameters that affect building foundation. We combine here in ARCGIS geological, geomorphological and geotechnical data to provide such a framework focusing on the capital city of Antananarivo in Madagascar. The city was initially constructed on basement hills covered with a thick loose weathered layer and is expanding into the alluvial lowland watered by the Ikopa River. About 221 boreholes with pressumeters and laboratory data provide a picture of the underground characteristics, and allow the computation of the soil bearing capacity, the key parameter we used to assess building suitability. Lithology, slope, land-use and ground water level are combine to build a first geotechnical map that is completed using a mapping of the soil bearing capacity combined with land-use and geohydrological constraints. The geotechnical maps divide the city into zones with different constructive conditions that can be use as a first tool for urban development planning. [less ▲]

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See detailWeathering pattern of Messinian lithothamnium limestones: implication about paleoclimatic conditions
Moulana, Meriem Lina ULiege; El Ouahabi, Meriam ULiege; Boulvain, Frédéric ULiege et al

in Geologica Belgica (2019)

Limestones are prevalent in Algeria. These formations since their deposition have been affected by a range of weathering, dissolution and recrystallization processes dependant of the paleoclimatic ... [more ▼]

Limestones are prevalent in Algeria. These formations since their deposition have been affected by a range of weathering, dissolution and recrystallization processes dependant of the paleoclimatic conditions they sustained. These transformations also affect the potential hazard that these karstic terrains represent. We focus here on the Boukadir Region situated at the foot of the Ouarsenis Mountain (Fig. 1). The region comprises the Ouarsenis northern piedmont composed of ~15o north dipping lithothamnium limestones of the Messinian period that rest unconformably upon blue marls of the upper Miocene, and to the south the E-W striking lower Chlef Basin filled by Plio-Quaternary sediments and flooded by the Chlef River. The lithothamnium carbonates rocks form a major deep aquifer in the Basin. The Basin is crossed along its southern edge by the Relizane strike-slip fault. In June 1988, there was a large collapse sinkhole of 60 m in diameter and 35 m of deep that occurred along the national road RN4 near the southern edge of the basin (LCTP, 1989). Drilling shows that sinkhole can be associated to lithothamnium limestones that were covered by more than 61 m of sediments at that location. No other sinkhole formed since this accident. In this study we investigate the weathering pattern of the lithothamnium limestones to unravel the likelihood of formation of large sinkholes in this formation. Boreholes and quarries show that the Messinian Calcareous limestones of the Boukadir region are deeply weathered and partly recrystallized calcareous rocks; the weathering affects its entire thickness reaching a maximum of 200 m. This weathering pattern is not visible a few kilometres more to the east, in limestones having a similar origin. To unravel the specific paleoclimatic conditions that these limestones sustained, we combine field work and on selected samples, petrographic thin section and mineralogical (XRD) analysis and SEM observations. Field work in quarries and in the wadi shows that the lithothamnium limestones are composed of altering sandstone rich beds with a calcareous cement and bioconstructions rich beds. .. [less ▲]

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See detailTracking magma movements in the Virunga volcanic province using seismic Amplitude Ratio Analysis (SARA)
Subira, Josué; Caudron, Corentin; Hubert, Aurelia ULiege et al

in Geologica Belgica (2019)

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See detailSedimentary evolution of the Sagara coastal area in Japan and its potential to preserve extreme wave deposits
Kempf, Philipp; Garrett, Ed; Fujuwara, Osamu et al

in Geologica Belgica (2019)

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See detailUse of high-resolution seismic reflection data in the paleogeographical reconstruction of shallow Lake Yamanaka (Fuji Five Lakes, Japan)
Lamair, Laura ULiege; Hubert, Aurelia ULiege; Yamamoto, S. et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (2019), 514

High-resolution seismic profiles, combined with the integration of published drilling data, provide a detailed paleoenvironmental history of Lake Yamanaka (Fuji Five Lakes, Japan). This study presents a ... [more ▼]

High-resolution seismic profiles, combined with the integration of published drilling data, provide a detailed paleoenvironmental history of Lake Yamanaka (Fuji Five Lakes, Japan). This study presents a detailed analysis of the different depositional stages of the area currently occupied by Lake Yamanaka (floodplain wetland, river and lake). From ca. 5500 cal yr BP to ca. 5050 cal yr BP, the Yamanaka basin was occupied by floodplain wetlands. During that period, the landscape was very stable and erosion on northeastern flank of Mt. Fuji was relatively limited. From ca. 5050 cal yr BP to ca. 3050 cal yr BP, the water level increased and the floodplain wetlands became a lake. From ca. 3050 cal yr BP to ca. 2050 cal yr BP, the water level progressively decreased, leading to a reduction in lake extent. During this lowering of the lake's water level, a 1 km2 mass-transport deposit modified the physiography of the lake floor. From ca. 2050 cal yr BP to ca. 1050 cal yr BP, the lake disappeared and a river flowing towards the northwest occupied the depression. Ponds occupied morphological lows formed by mass transport deposits. From ca. 1050 cal yr BP to the present day, the lake water level rose again, connecting the ponds with the main lake. Since then, the lake water level has continued to rise to the current level. Lake water level fluctuations are the results of several factors that could be interconnected: (i) changes in precipitation rates; (ii) margin destabilization (the Yamanaka mass-transport deposit), (iii) changes in river inlets and therefore variation in water supplies, (iv) volcanic eruptions (scoria fall-out and lava flows) and (v) changes in vegetation cover. This study highlights the importance of coupling sediment cores and high-resolution seismic reflection profiling to identify lateral variation and modification of sedimentary inputs through time. [less ▲]

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See detailÉvaluation du risque karstique de la région de BOUKADIR (Chlef-Algérie)
Moulana, Meriem Lina ULiege; Guendouz, Mostefa; Hubert, Aurelia ULiege

Poster (2018, September)

La commune de Boukadir, (ex Charon) dans la wilaya de Chlef au nord-ouest d’Algérie, n’a jamais été classée parmi les régions karstiques d'Algérie malgré la grande doline d’effondrement en juin 1988 de ... [more ▼]

La commune de Boukadir, (ex Charon) dans la wilaya de Chlef au nord-ouest d’Algérie, n’a jamais été classée parmi les régions karstiques d'Algérie malgré la grande doline d’effondrement en juin 1988 de 60m de diamètre et 35m de profondeur sur la route nationale. Boukadir se trouve au piémont nord de la montagne de l’Ouarsenis, sur la bordure sud de la plaine de 20 km de large du bas Chelif traversée par Oued Chlef. Le piémont septentrional de la chaîne de Ouarsenis est composé de calcaire à Lithothamniée subhorizontal d’âge miocène supérieur (messinien). Au niveau de la plaine et de l'effondrement, les roches carbonatées sont recouvertes de sédiments plio-quaternaires, là où les infrastructures (RN4, autoroute Est-Ouest d’Algérie A1) et villages (Boukadir, 41 655 habitants) sont situés. Afin d'évaluer le risque karstique, nous combinons différentes approches... [less ▲]

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See detailPaleoearthquakes recorded in the Fuji Five Lakes during the last ca. 6000 years (Fuji Five Lakes, Japan
Lamair, Laura ULiege; Hubert, Aurelia ULiege; Yamamoto, Shinya et al

Conference (2018, May)

In Japan, one pioneering lacustrine paleoseismological study was conducted in Lake Biwa in the 1990s. However, despite the high seismicity of Japan, the field of lacustrine paleoseismology did not expand ... [more ▼]

In Japan, one pioneering lacustrine paleoseismological study was conducted in Lake Biwa in the 1990s. However, despite the high seismicity of Japan, the field of lacustrine paleoseismology did not expand. Paleoseismological studies were more focused on inland trenches and coastal records. The paleoseismological data obtained by that way covers the last ~6000 years but contains hiatuses. Using lacustrine sediment allows us to span the same time period and to have a continuous record. Here, we present the second lacustrine paleoseismological study conducted in Japan. The Fuji Five Lakes are situated close to the triple junction, where the North American Plate, the Eurasian plate and the Philippine Sea Plate meet. Therefore, the region can be impacted by megathrust earthquakes generated along the Nankai-Suruga and the Sagami subduction zones. In addition, intraplate earthquake may affect the Fuji Five Lakes region. In the framework of the QuakeRecNankai project, we investigated two of the Fuji Five Lakes, Lake Motosu and Lake Sai. Here, we present the paleoseismological record of Lake Motosu and Lake Sai over the last 6000 and 2000 years, respectively. The turbidites were identified based on geophysical (magnetic susceptibility, grainsize) and geochemical properties (XRD, XRF) as well as SEM analysis. The turbidites were dated by 210Pb/137Cs, 14C dating and correlated with historical earthquakes. For prehistorical earthquakes (i.e., before the 6th century), they were correlated with geological evidences recorded along the Eastern Honshu coastline (i.e., tsunami deposits, coastal uplift, emerged ridge beaches). Over the last 6000 years, seismo-turbidites occurred with a mean recurrence time of 184±8 years. The near absence of large mass-transport deposits in the last 6000 years suggest that earthquake shaking mostly induced the remobilization of thin veneers of sediments in Lake Motosu. In Lake Sai, the earthquake fingerprint differs from Lake Motosu. Over the last 1200 years, past earthquake shaking induced turbidites, delta collapse and liquefaction (sediment volcanoes). [less ▲]

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See detailNatural hazards recorded in the Fuji Five Lakes: earthquake shaking, typhoon induced flooding and volcanic eruptions ral hazards recorded in the Fuji Five Lakes: earthquake shaking, typhoon induced flooding and volcanic eruptions
Hubert, Aurelia ULiege; Lamair, Laura ULiege; Yamamoto, Shinya et al

Conference (2018, May)

The 2014-2018 QuakeRecNankai project (acronym for "Paleo-tsunami and earthquake records of ruptures along the Nankai Trough, offshore South-Central Japan") funded by the Belgium Sciences Policy Office ... [more ▼]

The 2014-2018 QuakeRecNankai project (acronym for "Paleo-tsunami and earthquake records of ruptures along the Nankai Trough, offshore South-Central Japan") funded by the Belgium Sciences Policy Office focuses on the Fuji Five Lake area (central Japan) with the aim of a better understanding of the spatial and temporal recurrence of natural disasters. The region is susceptible to be impacted by natural hazards such as earthquake shaking, typhoon-induced floods and volcanic eruptions. The study location for natural hazard disaster is highly relevant since Mt. Fuji and the Fuji Five Lakes were recognized as a world heritage site in 2013 with about 300 000 tourists visiting the area every year. Within the framework of the project, the lacustrine sediments from Lake Motosu, Lake Sai and Lake Yamanaka were investigated and used to reconstruct the natural hazard history of the region. In the sedimentary infill of Lake Motosu, mass-transport deposits and turbidites triggered by earthquakes were recorded. Over the last ca. 6000 years, the mean recurrence time of seismic event triggering turbidites in Lake Motosu is 184±8 years. A comparison between the age of the turbidites and historical and paleoseismological records suggest that earthquake shaking impacting the Fuji Five Lakes area can be attributed mostly to large magnitude earthquakes occurring along the Sagami trench or along the Nankai-Suruga Subduction Zone. The two most recent earthquakes occurring along these subduction zones (i.e., the 1944 Showa Tonankai and the 1923 Kanto earthquakes) were recorded. By contrast with the sedimentary record of Lake Motosu, the lacustrine sediments collected in Lake Sai are a good archive for flood events. Detrital layers associated with the debris flow triggered by the 1966 Typhoon Ida (189 killed people, 3.9 millions yens damages) were identified, as well as other flood events associated with extreme precipitation events. Regarding volcanic eruptions, Lake Yamanaka and its catchment were repeatedly impacted by scoria fall-out due to their proximity to the Mt. Fuji volcano and the westerly wind direction . The last eruption (Hoei, A.D. 1707) strongly affected the lacustrine sedimentation and has a long-term effect on the catchment and on the lake, due to the sealing of the underlying sediments by the thick scoria layer. The geolimnology study of the Fuji Five Lakes gave us a better comprehension of the long-term recurrence of natural hazards affecting the region as well as their effects on the environment. [less ▲]

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See detailKarstic hazard assessment combining geomorphological and geological data in the region of BOUKADIR (Chlef, Algeria)
Moulana, Meriem Lina ULiege; Guendouz, Mostefa; Hubert, Aurelia ULiege

Poster (2018, April 13)

In 1988, a large collapse crater of 60m in diameter and 35m of deep occurred in the national road RN4 linking the wilaya of Algiers to Oran, exactly in the region of Boukadir located in the northern ... [more ▼]

In 1988, a large collapse crater of 60m in diameter and 35m of deep occurred in the national road RN4 linking the wilaya of Algiers to Oran, exactly in the region of Boukadir located in the northern piedmont of Ouarsenis in Algeria. The cover collapse sinkhole is located in the Boukadir plain, where the Chlef river is running, at the foot of the 723m high Oursenis Mt, composed of Lithothamnion limestones of the Messinian (uppermost stage of the Miocene). In Algeria, there are many karst areas like Tlemcen (karstification well developed at depth), Saida (karstification well developed at the surface), or the calcareous ridge of Djurdjura, Jijel... But the area of Boukadir has never been defined as a karstic region despite the 1988 sinkhole and the various karstic forms that we mapped in Oursenis Mt at the surface.We focus in this study on the Boukadir plain at the foot of the Oursenis range, where the carbonate rocks are covered by younger sediments, and where the infrastructures (RN4, highway from the east of Algeria to the West) and villages (Boukadir, 41,655 inhabitants) are located. To assess karstic hazard and related risk for the two major infractructures running at the foot of the Ouarsenis Mt, we combine geological, geomorphological and hydrological data. The examination of the geomorphology using aerial photographs, DEM and satellite images reveals the absence of any subsidence sinkhole, which is related to the fact that the covering sediments contain a significant amount of clay. Indeed the Lithothamnion limestones are covered by the marine marls of the Astien deposited during the Pliocene and clayey continental deposits of the Villafranchien formation (Upper Pliocene). The combination of surface geology with boreholes in the Boukadir plain reveals that the reef Lithothamnion limestsones does to extend across the Boukadir plain. The karstic hazard is thus restricted to a 2km wide narrow band at the foot of the Oursenis Mt. [less ▲]

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See detailKarstic Hazard in BOUKADIR (Chlef-Algeria) and its potential socio-economic impact
Moulana, Meriem Lina ULiege; Guendouz, Mostefa; Hubert, Aurelia ULiege

Conference (2018, March 16)

Boukadir, the municipality of the Wilaya of Chlef located west of Algiers has never been defined as a karstic region of Algeria despite the formation of a large collapse sinkhole in June 1988. The ... [more ▼]

Boukadir, the municipality of the Wilaya of Chlef located west of Algiers has never been defined as a karstic region of Algeria despite the formation of a large collapse sinkhole in June 1988. The sinkhole formed a crater with 60m wide and 35 m deep across the national road RN4 linking the Wilaya of Algiers to Oran. The municipality of Boukadir is located near southern edge of a 20 km wide plain flooded by the Chlef River bounded to the south by the Ouarsenis mountain range. The northern piedmont of the Ouarsenis Range is composed of Lithothamnion limestones of the tertiary that form a 25° dipping structural surface. Traces of karstification were founded in these Lithothamnion limestones outcropping at the surface. At the level of the plain and of the collapse sinkhole, the carbonate rocks are covered with younger sediments (quaternary alluviums). In order to objectively evaluate the hazard in the covered karst, we combine a range of boreholes to unravel the geometry of the carbonates and its cover. The characteristics of the limestones are evaluated combining XRD, XRF and thin sections in order to evaluate its dissolution potential. The socio-economic context is reviewed (population, industry, agriculture...) to discuss the karstic risk. [less ▲]

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See detailInter-techniques comparison of PIXE and XRF for Lake sediments
El Ouahabi, Meriam ULiege; Chene, Grégoire ULiege; Strivay, David ULiege et al

in Journal of Analytical Atomic Spectrometry (2018), 33(883 - 892),

In this paper we describe a validation procedure for chemical analysis of major elements and some minor elements as Sr, Cr, Ni, Zn and Zr in heterogeneous geological sediments. The procedure applies two ... [more ▼]

In this paper we describe a validation procedure for chemical analysis of major elements and some minor elements as Sr, Cr, Ni, Zn and Zr in heterogeneous geological sediments. The procedure applies two distinct techniques (PIXE and XRF) to the analysis of sediments. In this work an inter-technique comparison of the heterogeneous lacustrine sediments from the Amik Lake in the vicinity of the Roman city of Antioch (SE, Turkey) was carried out. Dried raw samples and with the addition of linking powder were analyzed using PIXE performed on the “Arkeo” beam line of the University of Liège AVF-Cyclotron and XRF (University of Liège). The aim of this work was to compare PIXE and XRF analysis with the set-ups routinely in use in the two laboratories. The purpose was also to determine the best combination of techniques and sample preparation protocol to be applied for heterogeneous sediments and the main elements of interest for each specific technique. The results are in agreement among the two techniques, with discrepancies concerning almost lighter and minor elements. These differences are related mainly to the texture of the sediments and the intrinsic features of the XRF and PIXE techniques. Major and selected minor elements are sensitive to the grain-size and the porosity of the samples. However, the accuracy of both XRF and PIXE requires the reduction of the grain-size or addition of linking powder to the sediments to fill the voids in order to increase the intensities of both lighter and minor elements. The results demonstrate the critical importance of sample treatment prior to analysis as well as the necessity of several measurement points and replicates to ensure the accuracy of the PIXE results. [less ▲]

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