Quelques Publications 2014-2018:
Adel Boussaïd, Nouari Souiher, Charline Dubois et Serge Schmitz
Cybergeo : European Journal of Geography. 2018. ; DOI : 10.4000/cybergeo.29257.

Cet article analyse les modes d’habiter et les pratiques agro-sylvo-pastorales de 188 familles dans une région steppique de l’Atlas Saharien. La population rurale y est désormais sédentaire. Le cas de la Wilaya de Djelfa permet de comprendre comment ces modes d’habiter s’inscrivent dans les divers milieux locaux et quels sont leurs impacts potentiels sur la désertification. Il ressort des observations de terrain, des enquêtes et des analyses statistiques qu’en plus d’exploiter les ressources végétales locales, les chefs de ménages interrogés dans quatre milieux différents (forestier, à matorral, steppique, dunaire et chott) pratiquent la supplémentation pour leurs troupeaux, ce qui a pour conséquence d’augmenter la taille de ceux-ci et d’intensifier le surpâturage. De même, l’approvisionnement en eau n’est plus traditionnel : si certains surexploitent les nappes aquifères sous-jacentes, la plupart des agropasteurs ont recours aux camions citernes. L’adaptation des modes d’habiter et d’exploiter le milieu est fortement déterminée par le capital du ménage qui permet de suppléer aux manquements locaux, avec cependant des conséquences importantes sur l’accentuation de la désertification.
Mots-clés : Pratiques, habiter, steppe semi-aride, paysage, pâturage, désertification, Djelfa
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Analele Universităţii din Oradea,, Seria Geografie XXVIII, no. 2//2018, pp. 138-148

This paper presents a three-step approach to evaluate and map mass movement risk. First, hazard and vulnerability, the two components of mass movement risk, are evaluated through the use of a Weighted Product Method (WPM) borrowed to the Multi-Attribute Utility Theory (MAUT). The model evaluates each potential action a  A (set of potential actions) according to a set of attributes, points of view and criteria i, i = 1, ..., n, from gi measurement scales. The criteria retained are environmental factors of susceptibility to landslides and surrounding elements at risk (stakes). In a second phase, the risk is estimated by the product of its two components. Finally, the spatial mass movement risk is determined by crossing the susceptibility (hazard) and consequences (vulnerability) maps. The method has been tested in the area of Aїn el Hammam in the basin of Tizi-Ouzou (Algerian Tell).
Key words: landslide, rock fall, multi-criteria analysis, modelling, GIS
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Fahem Djouder, Makhlouf Boutiba.
Arabian Journal of Geosciences; July 2017, 10:299.

The study area (the Gulf of Bejaia) is a coastal zone of about 70 km long in the eastern-central part of the Algerian coast. The coastline characterized by sandy beaches, hotels and tourist facilities, airport, port, villages and towns has known during these last decades several threats like storms, floods and erosion. The present work concerns the mapping of the physical and socioeconomic vulnerability of the Gulf Coast of Bejaia to sea level rise, using Coastal Vulnerability Index (CVI) and geospatial tools. The Physical CVI (CVIPhys) is calculated from seven physical variables: geomorphology, coastal slope, coastal regional elevation, sea level rise rate, shoreline erosion/accretion rates, tidal range and significant wave height. On the other hand, the parameters population, cultural heritage, roads, railways, land use and conservation designation constitute, for their part, the socioeconomic CVI (CVIeco). The values obtained from the calculation of CVIPhys vary between 3.53 and 81.83. These results revealed that 22.42 km of the studied coastline has a low physical vulnerability, 21.68 km a high vulnerability and 15.83 km a very high vulnerability, indicating that the most part of the coastline (53.59%) is vulnerable to sea level rise. According to the obtained values of CVIeco, the most vulnerable areas of high and very high risk represent 31.81 km of the total coastline. They were found along the western (Bejaia and Tichy) and eastern (Aokas, Souk El Tenine and Melbou) coast, while the least vulnerable stretches, covering 38.19 km of the total length of the coast, occupy the rest of the area. This study highlighted areas that will be most affected by future sea level rise (SLR) and storm events. It revealed that several development projects of Bejaia Gulf Coast, including tourist expansion areas, are planned in sites identified as very vulnerable. The results obtained from this assessment could guide local planners and decision-makers in developing coastal management plans in the most vulnerable areas.
Keywords Mediterranean Sea level rise Gulf Coast of Bejaia CVI Geomorphology Risk Geographical information systems.
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Djamal Akziz & Mostefa Guendouz & Mohamed Said Guettouche & Tahar Khelil
Arabian Journal of Geosciences (2018) 11:121.

At the western Sahel of Algiers, the watercourse of the Mazafran river is perpendicular to the Sahel fold, forming a gorge that has
developed in a tectono-eustatic context characteristic of the Sahel region. This gorge has formed in a regime of superimposition
which involves the evolution of antecedence in relation to the Sahel uplift. This deduction is the result of multiple analyses that are
based on a stratigraphic study which characterizes the succession of continental and marine deposits and the analyses of lineament
map of tectonic evolution during the Quaternary which is marked by the Sahel folding. In order to correlate the chronology
between the fluvial and marine sedimentary dynamics, a geomorphological study of theMazafran alluvial terraces associated with
the paleoshorelines was realized. The obtained results reveal that the development of the Mazafran river gorge is complex.
Keywords Superimposition . Antecedence . Tectono-eustatic . Stratigraphy . Alluvial terraces
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Djouher Saadoud, Mohamed Hassani, Francisco José Martin Peinado, Mohamed Saïd Guettouche.
Aeolian Research, Volume 32, June 2018, Pages 24–34, ELSEIVER.

Wind erosion is one of the most serious environmental problems in Algeria that threatens human activities and socio-economic development. The main goal of this study is to apply a fuzzy logic approach to wind erosion sensitivity mapping in the Laghouat region, Algeria. Six causative factors, obtained by applying fuzzy membership functions to each used parameter, are considered: soil, vegetation cover, wind factor, soil dryness, land topography and land cover sensitivity. Different fuzzy operators (AND, OR, SUM, PRODUCT, and GAMMA) are applied to generate wind-erosion hazard map. Success rate curves reveal that the fuzzy gamma (γ) operator, with γ equal to 0.9, gives the best prediction accuracy with an area under curve of 85.2%. The resulting wind-erosion sensitivity map delineates the area into different zones of five relative sensitivity classes: very high, high, moderate, low and very low. The estimated result was verified by field measurements and the high statistically significant value of a chi-square test.
Keywords: Wind erosion; Fuzzy logic; GIS; Remote sensing; Hazard; Laghouat
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Boudjema Sehl, Mohamed Said Guettouche, Hocine Ait Mouheb2, María Teresa Camacho Olmedo
Arab J Geosci (April 2018, 11:143 )
Modeling techniques have the power to predict land use change. Our research had three main aims: firstly, to compare and contrast the predictive performance of individual models versus consensus methods; secondly, to compare the different consensus methods; and finally, to compare their predictive performance for generalized and marginal land uses in the environment in the study area. Seven individual models were used to generate the suitability maps for each type of land use in Zahrez El Gharbi (Algeria), characterized by the suitability values for their occurrence. Seven consensus methods were created by combining the individual models. The predictive performance of the individual models and of the consensus methods was assessed by calculating the area under the curve (AUC). For each type of land use, the predictive quality of the consensus methods was considerably better than that of the individual models. The weighted averages method (WA) proved the most efficient of the seven consensus methods. The types of land use have a significant influence on the predictive quality, in that the AUC values increase in line with increases in the marginality of the particular type of land use. The improvements in predictive quality achieved by consensus methods in general and the weighted averages method (WA) in particular would substantially resolve the different sources of uncertainties resulting from the use of individual models and from the environmental characteristics of the different types of land use.
Keywords: Individual predictive model, Consensus method, Land use Suitability, Environmental marginality, Predictive performance
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Kalla Mohamed Issam and Guettouche Mohamed Said.
International Journal of GEOMATE, Dec., 2017, Vol. 13, Issue 40, pp. 9 - 15
Special Issue on Science, Engineering & Environment, ISSN: 2186-2990, Japan

If the typology of epidemics varies considerably, their causes remain substantially related to many physical environment factors. The fact remains that the problem of vector-borne diseases is complex in view of the diversity of these diseases, the large number of vulnerabilities associated with them, and also the objective assessment of the impact of each of these factors. The use of geomatic tools, such as geographical information systems (GIS) and remote sensing techniques as spatial environmental phenomena and through the implementation of a GIS database, has enabled us to highlight the spatial distribution of these diseases and their magnitude, and has allowed us to subsequently relate them to some environmental factors that might explain the emergence of the disease and its importance. The results clearly show that approximately 48.89% of the total area of the province was found to be highly vulnerable, 2.83% at moderate vulnerability, while 48.28% of the province had low vulnerability.
Keywords: Batna, Epidemics, Geomatics, Cutaneous Leishmaniasis, GIS, Vulnerability.
MEFTAH (Southeastern Algiers Region, Algeria).

AMRAOUI Saliha, BOUTALEB Abdelhak, SOUIHER Nouari & BERDOUS Dalila
Arabian Journal of Geosciences November 2017, 10:464

Cement’s dust particles contamination on soil has received a good amount of attention due to toxicity persistence in the environment. It must be noted that cement dust falls are enriched in toxic heavy metals, which can spread throughout a large area by wind and rain then accumulate on plants, animals, and soils, thus ultimately affecting human health. For this purpose, a study was achieved to evaluate the potential accumulation and spatial distribution of heavy metals in topsoils surrounding the Meftah cement factory, situated at the southeastern of Algiers region. Sixty six soil samples were collected following six directions (east, northeast, north, northwest, west, and southwest) from cement factory on a radius of 3.5 km approximately. The physicochemical parameters, such as the pH, the conductivity, and the organic matter of these samples were determined. The concentration of the Cd, Cu, Pb, and Zn elements, in soil samples, were determined with flame atomic absorption spectrophotometry (FAAS) method and the data generated were analyzed statistically. Thus, the enrichment factor (EF), pollution index (PI), contamination factor (CF), pollution load index (PLI), geoaccumulation index (Igeo), and principal component analysis (PCA) was performed to the dataset in order to calculate and estimate the enrichment of metal concentrations in soils. Moreover, mapping of the spatial distribution of heavy metals was carried out using geographic information system (GIS), to determine more polluted areas and accomplish the objectives of the study. The results of our analysis indicate that soils were polluted most significantly by metals such as lead, zinc, copper, and cadmium. It is thus important to keep systematic and continuous monitoring of the bag filter to reduce the cement dust emission. As possible, remediation activities be carried out on the soil of heavy metals and their derivatives to manage and suppress such pollution.
Keywords : Meftah Cement plant Soil Heavy metals Flame atomic absorption spectroscopy Geoaccumulation index Spatial distribution

CHERMALI Miloud ; BOUNIF Mohand Ouabdallah & BOUDELLA Amar
Arabian Journal of Geosciences. August 2017, 10:353

In order to investigate the effect of lateral errors on the sounding curves and subsequently their reduction, a site where considerable amount of inhomogeneities were thought to exist because of the excavations made during the building work previously carried out was chosen as a study area. Using the tripotential system of sounding promoted by Carpenter and Habberjam (Geophysics 21: 455-469, 1956), several soundings were performed. For some small electrode spacings, the three apparent resistivity curves were locally divergent indicating the existence of small-scale lateral errors; in other cases, these curves cross each other indicating the existence of additional observational errors. Some soundings showed continuous divergence of the three apparent resistivity curves as an indication of the existence of a major lateral discontinuity. Because of the interference of these disturbing effects, the interpretation of the soundings based on a horizontally layered earth is erroneous. One of these soundings containing these kinds of errors is taken as example. In order to reduce the effect of local inhomogeneities, an approach based on the linear filtering technique is suggested. As a check of the effectiveness of this method, the recalculated values of the two lateral error tests suggested by the authors were reduced when the three smoothed apparent resistivity curves were used. However, this method seemed more suitable for a flat trend data than for a data with a trend.
Keywords: Error Filtering Lateral Spectrum Resistivity

T. Bennour, M. S. Guettouche & E. Matinez Ibrra
Journal of Fundamental and Applied Sciences, September 2017

In Algeria, implementation, monitoring and exploitation of climate data, development and dissemination of periodic publications and climate assistance to users, are tasks of the
National Climatological Centre (NCC). Moreover, the effective management of this large volume of data requires the use of new technologies such as Geographic Information Systems
(GIS). In this context, the aim of the present work is to develop an IT solution on the Web, based on the use of Geographic Information Systems. The approach consists, first, to design
databases to store various data used (climatic and topographic) considering the functional needs such as the dissemination of data in several modes (read, download) and the possibility
direct data access from remote locations. Then the choice of technology and tools to implement a mapping solution that will allow, in addition to the functionality of storage and
distribution of different types of data, analysis of climate observations by using a web service whitin the WPS (Web Processing Service) standard.
Keywords: GIS, SIG-CLIMALG, climate data, WPS

Djouher Saadoud & Mohamed Saïd Guettouche & Mohamed Hassani & Francisco José Martin Peinado.
Arab J Geosci (2017) 10: 363. DOI 10.1007/s12517-017-3139-1

Wind-erosion risk is a challenge that threatens land development in dry-land regions. Soil analysis,
remote sensing, climatic, vegetal cover and topographic data were used in a geographic information
system (GIS), using multi-criteria analysis (MCA) to map wind-erosion risk (Rwe) in Laghouat,
Algeria. The approach was based on modelling the risk and incorporating topographic and climatic
The maps were coded according to their sensitivity to Wind erosion and to their socio-economic
potential, from low to very high. By overlapping the effects of these layers, qualitative maps were
drawn to reflect the potential sensitivity to wind erosion per unit area. The results indicated that
severe wind erosion affects mainly all the southern parts and some parts in the north of Laghouat,
where wind-erosion hazard (Hwe) is very high in 43% of the total area, and which was affected
mainly by natural parameters such as soil, topography and wind. The results also identified
features vulnerable to Rwe. The product of the hazard and the stake maps indicated the potential
risk areas that need preventive measures; this was more than half of the study area, making
it essential to undertake environmental management and land-use planning.
Keywords : Soil .Wind erosion . Laghouat . GIS . Remote sensing . Risk

Lyes Zazi, Abdelhak Boutaleb & Mohamed Said Guettouche.
Arab J Geosci (2017) 10:252
DOI 10.1007/s12517-017-3015-z

Applied in Djebel Meni (Northwestern of Algeria), this research highlights the results obtained from the supervised classification using the Spectral Angle Mapper (SAM) algorithm, through introducing the spectral signatures of illite, kaolinite, and montmorillonite, via Jet Propulsion Laboratory (JPL) spectral library. These results were compared to the ones of the SAM classification, which use spectral signatures obtained by the Sequential Maximum Angle Convex Cone (SMACC) endmembers extraction algorithm. This implies the ability to detect and identify any object present on the Earth’s surface, whether its nature is mineral, vegetal, or human made, from hyperspectral imaging. By extracting the spectral signatures with the SMACC algorithm and matching them to the current signatures of JPL spectral library, comparing spectral signatures with another is not an easy task. Indeed, for a better comparison and a more appropriate interpretation in the use of the SAM classification, the results obtained were very relatively convincing because, regarding very strong similarities. It appears also that the signatures extracted with SMACC occupy the same areas as those of the JPL spectral library. This method of detection and identification of any present object on the Earth’s surface is rather conclusive.
Keywords: Hyperion . Hyperspectral . SMACC . SAM . Clay minerals . Djebel Meni (NWAlgeria)
AND AUTOMATIC COMPUTATION. Case of jijelian sandy coast (East Algeria).

Saci Kermani, , Makhlouf Boutiba, Mostefa Guendouz, Mohamed Said Guettouche, Dalila Khelfani
Laboratory of Geomorphology and Georisks, Faculty of Earth Sciences, University of Sciences and Technology, Houari Boumedienne (USTHB), Algiers, Algeria
Received 7 March 2016, Revised 28 July 2016, Accepted 10 August 2016, Available online 17 August 2016.

Analysis and understanding of coastline variability and coastal erosion-accretion trends are important for scientists and local decision-makers for orienting regulation and decisions concerning coastal planning. This study focuses on the detection and analysis of historical changes in shoreline position of the Bay of Jijel (East -Algeria) occurred between 1960 and 2014. Shoreline changes along the Bay of Jijel were studied from multi-dated aerial photographs (1960, 1973 and 1988) and Quick-bird satellite image (2014). The correction of aerial photographs and satellite image was carried out using the remote sensing tools and Geographic Information System “GIS”. To attain our objective, the study area was divided into three sectors for analysis: (1) the beaches of Jijel, Tassoust in the western sector, (2) the central area encompasses beaches of El Kanar, El Mzair and SidiAbdelaziz, (3) the eastern sector contains the beaches of El Djnah and Beni Belaid. Net rates changes of shoreline position in time were calculated from several statistical methods End Point Rates (EPR), Linear Regression Rates (LRR) and Weighted Linear Regression (WLR). These net rates of coastline changes have been calculated, also, on three intervals of times (1960–1973, 1973–1988 and 1988–2014) and on a period (mid-centennial) of 54 years (1960–2014). The result shows that the study area is almost stable between 1960 and 1973 with a rate of change equal to −0.072 m/year. This rate of change, has negatively increased during episodes time 1973–1988 and 1988–2014, with average values of −0.125 m/year and −0.85 m/year, respectively. Over a mid-secular period, the coast has experienced an average net rate global of changes equal to −0.459 m/year. This recession of the coastline is due to the combined action of the cumulative effects of stormy climate of the coast and various human actions on the Jijelian coastal strip.

Corrected aerial photographs; Satellite image (QuickBird); GIS; Shoreline changes accretion/erosion; EPR & LRR
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EAST OF ALGERIA: Indicators of sediment sources and transport, and deposition environments.

Saci Kermani, Makhlouf Boutiba, Abdelhak Boutaleb , Nathalie Fagel

The identification of bulk, clay (upper 2 μm), and heavy (63–200 μm) minerals has been investigated on 42 coastal samples along the Jijel bay (Eastern Algeria). The mineralogical assemblages are used to identify the mineral sources and to interpret the mineral distribution. The samples were subjected to grain-size analysis by sieving and by X-ray diffraction on powder (bulk mineralogy) and on oriented aggregates (clay fraction). The bulk fraction is composed by muscovite, plagioclase, calcite, anhydrite, clay fraction, and a predominance of quartz (11 to 45 %). Clay fraction is composed of kaolinite, chlorite, smectite, interstratified minerals, and a predominance of illite (43–65 %). In addition, the heavy minerals assemblages of sediments have been identified by binocular observation, X-ray diffraction, and optical microscope. The heavy minerals are dominated by opaque minerals (16–65 %) associated with variable proportions of muscovite, chlorite, kyanite, sillimanite, biotite, pyroxene, amphibole, garnet, epidote, zircon, tourmaline, and rutile. Both fluvial hydrodynamic and marine agents control the sediment distribution along the coast. Indeed, the passage from areas in accretion toward those in erosion has caused a concentration in heavy minerals on coastal sections in recession; however, the light minerals were moved selectively toward accretional areas. The heavy mineral assemblages present in rivers sediment indicate that they were delivered to the coast in a highly selective manner. This assemblage of heavy mineral is also present with high concentration in a variety of fluvio-marine environments such as river mouths, coastal dunes, and beaches. These sediments are derived from the various geological formations (metamorphic formations of the basement, magmatic rocks, and other sedimentary rocks) observed in the watershed.

Keywords: Heavy minerals Clay minerals Grain size Sediment sources Sediment distribution Jijel coast


Detection and analysis of historical variations in the shoreline, using digital aerial photos, satellite images, and topographic surveys DGPS: case of the Bejaia bay (East Algeria)

Katia Ayadi, Makhlouf Boutiba, & François Sabatier & Mohamed Said Guettouche.
Arab J Geosci (2016) 9:1-12. DOI 10.1007/s12517-015-2043-9

The Bejaia coastline is one of the most beautiful and attractive coastlines in Algeria; this is due to its landscape and ecological diversity running along it. The eastern coast of Bejaia is formed by a wide stretch of sand, occupying the bottom of the bay. Its beaches are fed by sediments carried by two main wadis that debouch into the bay: Soummam in the west and Agrioun in the east. The undertaken work in this article focuses on the study of coastal erosion, which has a significant damage on the natural patrimony. This erosion risk in perpetual evolution, by location, is dramatically affecting the beautiful sandy beaches and various infrastructures over all the coast length of the Bejaia bay. In order to map and evaluate this risk, a methodological approach has been followed.
This approach is mainly based on a diachronic variation analysis in the position of the shoreline over a period of 60 years; based on a series of ortho-rectified aerial photos, satellite images, as well as DGPS topographic surveys on the ground. The results revealed significant variations in the position of the shoreline during the last 60 years, especially on both sides of Soummam and Agrioun wadis. The most observed retreat of the shoreline is in the western part of the coast, where the rate of evolution reached −7.89 m/year (beach of Sidi Ali Lebhar), whereas the shoreline retreat reached −1.75 m/year in the center of the bay and −2 m/year toward the east.

Keywords: Bejaia bay . Coastline . Aerial photographs . Advance . Retreat . Coastal erosion.


GIS-based landslide susceptibility zonation using bivariate statistical and expert approaches in the city of Constantine (Northeast Algeria).

Hamid Bourenane, Youcef Bouhadad, Mohamed Said Guettouche & Massinissa Braham
Bulletin of Engineering Geology and the Environment May 2015, Volume 74, Issue 2, pp 337-355. DOI 10.1007/s10064-014-0616-6. Springer-Verlag Berlin Heidelberg 2014.

The city of Constantine has suffered frequent landslides during the last few decades because of its geological, geomorphological, climatic and seismotectonic setting as well as anthropic activities. In this work we perform a landslide susceptibility zonation (LSZ) zonation by using bivariate statistical and expert approaches in GIS technology for this area. Firstly, a landslide inventory map was constructed from interpretation of aerial photographs, high resolution satellite images, field surveys and bibliographies. Then various causal factors such as lithology, slope, aspect, precipitation, land use, distance to streams, distance to faults and anthropogenic factors like distance to roads associated with landslide activity were considered and the corresponding thematic layers generated using GIS techniques. The relative importance of these layers in causing landslides has been evaluated using bivariate statistics and expert methods to generate LSZ maps. The expert-based method provided a subjective classification of the study area in terms of landslide susceptibility which does not completely fit the landslide field survey. However unlikely, the bivariate statistics-based method provided the most satisfying results and appears to be the most accurate. Indeed, results show that 27.2 % of the study area lies within a very high to high susceptibility zone that encompasses 73.64 % of the existing landslides. Moderate, low and very low susceptibility zones cover, respectively, 25.7, 21.7 and 25.4 % of the study area. The LSZ maps generated may serve as useful tools for land management and planning in the Constantine region.

Keywords: Landslide susceptibility zonation GIS Expert-based Bivariate statistics Algeria


Index of extraction of water surfaces from Landsat 7 ETM+ images.

Mohamed Hassani & Moulley Charaf Chabou, Mohamed Hamoudi & Mohand Said Guettouche
Arabian Journal of Geosciences. June 2015, Volume 8, Issue 6, pp 3381-3389 DOI 10.1007/s12517-014-1475-y.

The aim of this study was to develop an index of water surfaces (IWS) for separating the water surfaces from other types of land use, by using the images of Landsat 7 ETM+. The index was applied on four areas characterized by different types of land use from different regions in Algeria. The first is from the center of Algeria (Landsat ETM+ scene: 195−36 acquired March 24, 2001); the second is from the east of Algeria (Landsat ETM+ scene: 193−35 acquired March 24, 2000); the third is from the west of Algeria (Landsat ETM+ scene: 197−36 acquired February 16, 2000); and the fourth is from the south of Algeria (Landsat ETM + scene: 197−43 acquired February 16, 2000). The results showed that the application of the IWS on the different tested areas can distinguish clearly the surface water from the other land use (basin dams, wadis, Sebkha, and Chott). These findings indicated that this index can be used in the mapping of the water surfaces.

Keywords: Landsat ETM+ Spectral signature Land use Index of water surfaces


: Bulletin du Service Géologique National, 2014. Vol.25 ; N° 1, pp :33-53

Le gisement aurifère d'Amesmessa est situé dans le SW du Hoggar. Il est représenté par des lentilles et filons lenticulaires de quartz, encaissés essentiellement dans des mylonites-ultra mylonites, soulignant une méga-shearzone. Celle-ci représente la zone de cisaillement 2°30' Est-ouzzalienne (ZCEO) qui sépare le terrane d'In Ouzal, à l'ouest, du terrane de Tirek. Ces filons sont caractérisés par une très grande irrégularité dans la morphologie. La puissance et surtout dans la distribution des teneurs en Or. En plus, certaines zones bérésitisées (altération hydrothermale à quartz-carbonates-séricite-pyrite) supposées riches en minéralisation, sont dénudées d'or. Cette dispersion de l'or dans les filons, ainsi que la difficultés de cerner l'ampleur de son auréole de diffusion dans les roches encaissantes, pose un sérieux problème de calcul de réserves. Afin de palier à ces difficultés, une étude statistique et géostatistique a été entreprise.
L'étude statistique des paramètres teneur et puissance des corps minéralisés de la zone 8 d'Amesmessa, a permis de montrer que la teneur suit le modèle de dispersion selon la loi log-normale, alors que la puissance adopte le modèle de la loi normale.
L'étude géostatistique (variogrammes et krigeage) des variables régionales (puissance, teneur) de la zone étudiée, montre que la minéralisation présente une forme lenticulaire. La localisation des lentilles aurifères est montrée par les cartes d'isoteneur et d'isopuissance. Ces cartes ont été établies suivant un plan de projection vertical, sur la base des sondages réalisés par l'ORGM. La minéralisation étant sub-verticale, l'erreur induite par cette projection est insignifiante.
L'observation des cartes d'isoteneur et d'isopuissance, montre que la minéralisation se présente sous forme de lintilles dont les plus riches sont près de la surface.

Mots-clès: Quartz aurifère-Shearzones-Géostatistique-Statistique - Amesmessa-Hoggar Occidental.


Contribution of Geomorphology to Modelling a Risk of Contamination by Diseases and Evaluation by Gis. Application in Blida (algeria)
Mohamed Said Guettouche, Amel Azrou & Kahina Souami

Risk management of contamination by waterborne diseases starts from its assessment.
This assessment has been subject of several research and many studies on mapping landscapes diseases have been developed. However the population vulnerability to water-borne diseases is an important part of risk; it represents, in fact, the exposed challenge to this scourge and therefore worth particular attention by decision makers. Thus, we propose in this work, a model for assessing the risk of contamination by diseases based on the principle of the weighted product. Application of the proposed model suggested to use of geomatics technologies to the spatialize level of risk.
Within this framework, a GIS was developed and applied in Blida (Algeria).

Published in abstract book of 3rd ScienceOne International Conference on Environmental Sciences 2014, glamorous city of Dubai on January 21-23, 2015. Page No. 49.

Landslide hazard mapping in the Constantine city, Northeast Algeria using frequency ratio, weighting factor, logistic regression, weights of evidence, and analytical hierarchy process methods.

Hamid Bourenane; Mohamed Said Guettouche; Youcef Bouhadad; & Massinissa Braham.

Landslides constitute the most widespread and damaging natural hazards in the Constantine city. They represent a significant constraint to development and urban planning. In order to reduce the risk related to potential landslide, there is a need to develop a comprehensive landslide hazard map (LHM) of the area for an efficient disaster management and for planning development activities. The purpose of this
research is to prepare and compare the LHMs of the Constantine city, by applying frequency ratio (FR), weighting factor (Wf), logistic regression (LR), weights of evidence (WOE), and analytical hierarchy process (AHP) methods used in a framework of the geographical information system (GIS).
Firstly, a landslide inventory map has been prepared based on the interpretation of aerial photographs, high resolution satellite images, fieldwork, and available literature. Secondly, eight landslide-conditioning factors such as lithology, slope, exposure, rainfall, land use, distance to drainage, distance to road, and distance to fault have been considered to establish LHMs using the FR, Wf, LR, WOE, and AHP models in GIS. For verification, the obtained LHMs have been validated comparing
the LHMs with the known landslide locations using the receiver operating characteristics curves (ROC). The validated results indicate that the FR method provides more accurate prediction (86.59 %) of LHMs than the WOE (82.38 %),
AHP (77.86 %), Wf (77.58 %), and LR (70.45 %) models On the other hand, the obtained results showed that all the used models in this study provided a good accuracy in predicting landslide hazard in Constantine city. The established maps can be used as useful tools for risk prevention and land use planning in the Constantine region.

Keywords Landslide hazard maps. GIS. Frequency ratio. Weighting factor. Logistic regression. Weights of evidence. Analytical hierarchy process. Constantine. Algeria