Centre de documentation
scientifique

Morphotectonic and morphodynamic investigations revealed by isobase surfaces analysis and derived differential mapping using GIS, Teboursouk area, northern Tunisia / Tarek Slama in Earth Science Informatics, vol 8 n° 4 (2015)  

Public [article]  inEarth Science Informatics > vol 8 n° 4 (2015) . - pp 759 - 773 Titre : Morphotectonic and morphodynamic investigations revealed by isobase surfaces analysis and derived differential mapping using GIS, Teboursouk area, northern Tunisia Type de document : Article/Communication Auteurs : Tarek Slama, Auteur ; Benoit Deffontaines , Auteur ; Mohamed Moncef Turki, Auteur Année de publication : 2015 Article en page(s) : pp 759 - 773 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG [Termes IGN] déformation de la croute terrestre [Termes IGN] faille géologique [Termes IGN] géomorphologie locale [Termes IGN] isoligne [Termes IGN] linéament [Termes IGN] modèle numérique de surface [Termes IGN] réseau hydrographique [Termes IGN] Trias [Termes IGN] Tunisie Résumé : (auteur) Teboursouk area within the northern Tunisian Atlas presents a complex and heterogeneous geological framework leading to various geomorphic landforms among them there are numerous Triassic salt extrusions having an evident impact on the topographic configuration, shaping and dynamics. Landforms characterization of the study area, by morphostructural and morphodynamic mapping, was carried out using the isobase approach which is mainly based on the construction of topographic base-level surface from each channel order. GIS environment and spatial data analysis tools have been used to perform this procedure using 10 m-grid DEM and digitized drainage network at a semi-detailed scale (1: 50 000). The analysis included the creation of isobase maps of 2nd, 3rd and 4th-order channels. Grid calculations allowed the construction of (1) a combined surface from 2nd and 3rd order and (2) a differential map which represents the topographic residual between present day surface (original DEM) and isobase of 4th order. In fact, qualitative analysis of different isobase surfaces shows a good delimitation of most morphostructures and highlights a model of an atypical morphostructure concerning the Triassic extrusion of Jebel ech Cheid (JEC). Isoline anomalies and disturbances have indicated that major morphotectonic lineaments, interpreted as fractures, trend NE-SW to NNE-SSW adapting to the regional strike-slip fault system in response to NW-SE late Alpine transpressive tectonics. Several isoline inflexions were, however, well correlated with observed tectonic fractures and some of them are considered to be closely related to basement as the 4th-order analysis demonstrates. In contrast, neotectonic features, active landforms and lineaments were quantitatively described and localized based on the differential mapping approach. Numéro de notice : A2015--071 Affiliation des auteurs : UPEM-LASTIG+Ext (2016-2019) Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s12145-015-0208-4 Date de publication en ligne : 25/01/2015 En ligne : http://dx.doi.org/10.1007/s12145-015-0208-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83255 [article]

Recent tectonic activity of the Gafsa fault through morphometric analysis: Southern Atlas of Tunisia / Mehdi Ben Hassen in Quaternary International, vol 338 ([04/08/2014])    

Public [article]  inQuaternary International > vol 338 [04/08/2014] . - pp 99 - 112 Titre : Recent tectonic activity of the Gafsa fault through morphometric analysis: Southern Atlas of Tunisia Type de document : Article/Communication Auteurs : Mehdi Ben Hassen, Auteur ; Benoit Deffontaines , Auteur ; Mohamed Moncef Turki, Auteur Année de publication : 2014 Article en page(s) : pp 99 - 112 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géologie [Termes IGN] faille géologique [Termes IGN] géomorphométrie [Termes IGN] modèle numérique de surface [Termes IGN] réseau hydrographique [Termes IGN] Tunisie Résumé : (auteur) This article focuses on the neotectonics of the southern Atlas of Tunisia based on morphometric analyses. Five major relevant morphometric parameters were processed and analyzed: residual topography, hypsometric index, drainage anomalies, maximum vertical curvature, and terrain roughness, and compared to the structural and tectonics of the study area. These are relevant to describe the topographic changes, and therefore suggest possible neotectonic activity. The analysis of these morphometric indices reveals that two structures in the study area (Jebels Ben Younes and Bou Ramli) are distinguished by a specific morphometric footprint: high residual topography, high hypsometric integral value of some watersheds (HI > 0.6), high frequency of drainage anomalies, high maximum vertical curvature, and high roughness index. The correlation of these geomorphic indices with the structural pattern of the study area confirms the neotectonic reactivation (dating from the Quaternary) and the dextral strike-slip component of the Gafsa fault (the major tectonic feature in the southern Atlas of Tunisia). Thus, the morphometric analysis of the Digital Elevation Model and the drainage network provide a more accurate insight into the morphodynamics of the study area. Numéro de notice : A2014-813 Affiliation des auteurs : UPEM-LASTIG+Ext (2016-2019) Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.quaint.2014.05.009 Date de publication en ligne : 03/06/2014 En ligne : https://doi.org/10.1016/j.quaint.2014.05.009 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90657 [article]

Documents numériques

en open access Recent tectonic activity of the Gafsa fault ... - pdf éditeur Adobe Acrobat PDF

Phosphate mine subsidences deduced from differential interferometry (DInSAR): The Moulares case example (southern Atlas of Tunisia) / Mehdi Ben Hassen in Comptes rendus : Géoscience, vol 343 n° 11-12 (November - December 2011)  

Public [article]  inComptes rendus : Géoscience > vol 343 n° 11-12 (November - December 2011) . - pp 729 - 737 Titre : Phosphate mine subsidences deduced from differential interferometry (DInSAR): The Moulares case example (southern Atlas of Tunisia) Titre original : Subsidences des mines de phosphates révélées par l’interférométrie différentielle (DInSAR) : exemple de Moulares (Atlas méridional de la Tunisie) Type de document : Article/Communication Auteurs : Mehdi Ben Hassen, Auteur ; Noamen Rebaï, Auteur ; Benoit Deffontaines , Auteur ; Mohamed Moncef Turki, Auteur ; Fredj Chaabani, Auteur Année de publication : 2011 Article en page(s) : pp 729 - 737 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications [Termes IGN] image ERS-SAR [Termes IGN] image radar [Termes IGN] interferométrie différentielle [Termes IGN] interféromètrie par radar à antenne synthétique [Termes IGN] mine [Termes IGN] subsidence [Termes IGN] Tunisie Résumé : (auteur) Tunisia is submitted to numerous small topographic displacements due to both the geodynamic of the Eurasian-African plates’ convergence, and to important anthropic actions such as oil production, underground water pumping, mine extraction and linked post-mining displacements. We propose herein to study the latter and locate, characterize, and quantify small topographic displacement fields due to the production of underground phosphate mines in central Tunisia. After having acquired and processed 17 radar images (ERS 1 and 2) of the central Tunisia (Gafsa area) through Differential Interferometry (DInSAR), we clearly observed local subsidence that we interprete as corresponding to mine exploitation of the underground Moulares Phosphates mines (southern Atlas of Tunisia). Field studies (circular normal faults located above the Phosphate extraction area) confirm the movement revealed by DinSAR. Also, DInSAR allows us to monitor temporal variations of the small vertical displacements on this specific area and since the collapse occurred near an urban area (Moulares city), this problem can be considered a potential anthropic risk. Numéro de notice : A2011-600 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : 10.1016/j.crte.2011.09.005 Date de publication en ligne : 08/11/2011 En ligne : https://doi.org/10.1016/j.crte.2011.09.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91646 [article]