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See detailInsights into a million-year-scale Rhenohercynian carbonate platform evolution through a multi-disciplinary approach: example of a GIvetian carbonate record from Belgium
Pas, Damien ULiege; Da Silva, Anne-Christine ULiege; Devleeschouwer, Xavier et al

in Geological Magazine (2017), 154(4), 707-739

In this paper we formulate answers to three important questions related to Givetian carbonate records and their use for reconstructing million-year past palaeoenvironmental changes. First, we provide ... [more ▼]

In this paper we formulate answers to three important questions related to Givetian carbonate records and their use for reconstructing million-year past palaeoenvironmental changes. First, we provide detailed illustrations of the fascinating diversity that shaped a significant shallow reefal platform during the early- to late-Givetian in the Rhenohercynian Ocean; secondly we improve the sedimentological model of the extensive Givetian carbonate platform in the Dinant Basin and thirdly we evaluate the application of magnetic susceptibility (MS) as a tool for long-term trend correlations and palaeoenvironmental reconstructions. These goals are reached by making sedimentological, geophysical and geochemical study of the La Thure section. Through the early-late Givetian interval we discerned eighteen microfacies ranging from a homoclinal ramp to a discontinuously rimmed shelf and then a drowning shelf. The comparison of these sedimentological results with those published in the south of the Dinant Syncline allowed us to provide an up to date model of the vertical and lateral environmental development for one of the largest Givetian carbonate platforms in Europe. This comparison also increased the knowledge on the facies belts distribution into the Dinant Basin and allowed us to highlight the Taghanic Event. Palaeo-redox proxies reveal a substantial change in the oxygenation level, from oxygen-depleted to more oxic condition, between middle and late Givetian. We demonstrated the relationship between variation in MS values and proxies for siliciclastic input (such as Si, Al). The La Thure is considered as a key section for the understanding of internal shelf settings bordering Laurussia’s south-eastern margin. [less ▲]

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See detailNEW SEDIMENTOLOGICAL DATA FROM TRIASSIC TO JURASSIC BOREHOLES (BONNERT, HAEBICHT, GROUFT, GRUND, CONSDORF) AND SECTIONS (TONTELANGE, DIFFERDANGE, RUMELANGE) FROM SOUTHERN BELGIUM AND LUXEMBOURG
Boulvain, Frédéric ULiege; Belanger, Isabelle; Colbach, Robert et al

in Professional Papers of the Geological Survey of Belgium (2017), 319

This study offers a detailed description of a series of Triassic to Jurassic representative boreholes (Bonnert, Haebicht, Grouft, Grund, Consdorf) and sections (Tontelange, Differdange, Rumelange) from ... [more ▼]

This study offers a detailed description of a series of Triassic to Jurassic representative boreholes (Bonnert, Haebicht, Grouft, Grund, Consdorf) and sections (Tontelange, Differdange, Rumelange) from southern Belgium and the Grand-Duchy of Luxembourg. Investigations provide information about microfacies, paleoenvironments and magnetic susceptibility (MS). Three sets of microfacies, corresponding to three different sedimentary systems were needed in order to address the complexity of the paleoenvironments: a transgressive mixed siliciclastic-carbonate ramp system for the Triassic to Lower Jurassic (Toarcian) interval (microfacies TT1-8), and, for the Middle Jurassic, an early transgressive low productivity mixed ramp system for the Aalenian (microfacies A1-2) and a transgressive carbonate ramp for the Lower Bajocian (microfacies B1-3). A comparison of the MS and microfacies curves shows a clear correlation between the two, suggesting that the MS signal is primary. Moreover, the MS values regularly decrease from the marine distal (TT1) to the marine proximal microfacies (TT5), with relatively weak mean MS values for sandstones and limestones, and high mean MS values for marls, argillites and ironstone. This relationship is interpreted as the consequence of local water agitation in the shallower parts of a ramp, preventing the detrital particles from settling down and to the higher sedimentation rate that dilutes the magnetic and/or paramagnetic minerals. [less ▲]

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See detailMultiple dating approach (14C, 230Th/U and 36Cl) of tsunami-transported reef-top boulders on Bonaire (Leeward Antilles) – Current achievements and challenges
RIXHON, G.; MAY, S.M.; ENGEL, M. et al

in Marine Geology (2017)

Dating the transport/deposition time of supratidal coarse-clast deposits is difficult, limiting their value for inferring frequency-magnitude patterns of high-energy wave events. On Bonaire (Leeward ... [more ▼]

Dating the transport/deposition time of supratidal coarse-clast deposits is difficult, limiting their value for inferring frequency-magnitude patterns of high-energy wave events. On Bonaire (Leeward Antilles, Caribbean), these deposits form prominent landforms, and transport by one or several Holocene tsunamis is assumed at least for the largest clasts. Although a large dataset of 14C and electron spin resonance (ESR) ages is available for major coral rubble ridges and ramparts, it is still debated whether these data reflect the timing of major events, and how these datasets are biased by the reworking of coral fragments. As an attempt to overcome the current challenges for dating the dislocation of singular boulders, three distinct dating methods are implemented and compared: (i) 14C dating of boring bivalves attached to the boulders; (ii) 230Th/U dating of post-depositional, secondary calcite flowstone and subaerial microbialites at the underside of the boulders; and (iii) surface exposure dating of overturned boulders via 36Cl concentration measurements in corals. Approaches (ii) and (iii) have never been applied to coastal boulder deposits so far. The three 14C age estimates are older than 40 ka, i.e. most probably beyond the applicability of the method, which is attributed to post-depositional diagenetic processes, shedding doubt on the usefulness of this method in the local context. The remarkably convergent 230Th/U ages, all pointing to the Late Holocene period (1.0–1.6 ka), are minimum ages for the transport event(s). The microbialite sample yields an age of 1.23 ± 0.23 ka and both flowstone samples are in stratigraphic order: the older (onset of carbonate precipitation) and younger flowstone layers yield ages of 1.59 ± 0.03 and 1.23 ± 0.03 ka, respectively. Four coral samples collected from the topside of overturned boulders yielded similar 36Cl concentration measurements. However, the computed ages are affected by large uncertainties, mostly due to the high natural chlorine concentration. After correction for the inherited component and chemical denudation since platform emergence (inducing additional uncertainty), the calculated 36Cl ages cluster between 2.5 ± 1.3 and 3.0 ± 1.4 ka for three of four boulders whilst the fourth one yields an age of 6.1 ± 1.8 ka, probably related to a higher inheritance. These 230Th/U and 36Cl age estimates are coherent with a suggested tsunami age of < 3.3 ka obtained from the investigation of allochthonous shell horizons in sediment cores of northwestern Bonaire. Whilst 230Th/U dating of post-depositional calcite flowstone appears to be the most robust and/or accurate approach, these results illustrate the potential and current limitations of the applied methods for dating the dislocation of supralittoral boulders in carbonate-reef settings. [less ▲]

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See detailAn Introduction to the Geology of Belgium and Luxembourg
Boulvain, Frédéric ULiege; Vandenberghe, Noël

in Demoulin, Alain (Ed.) Landscapes and Landforms of Belgium and Luxembourg (2017)

Belgium and the Grand-Duchy of Luxembourg show surprising geological diversity over their small combined area of 33,114 km2. Almost all types of sedimentary rocks crop out and are generally preserved ... [more ▼]

Belgium and the Grand-Duchy of Luxembourg show surprising geological diversity over their small combined area of 33,114 km2. Almost all types of sedimentary rocks crop out and are generally preserved along well-described and easily accessible sections or in quarries. Several sections are known worldwide and are visited for stratigraphic or sedimentological purposes. Magmatic rocks are not abundant and metamorphic rocks are restricted to slates. The stratigraphic scale ranges from the Cambrian to the Quaternary, which translates to a half billion years of Earth history. This chapter provides a comprehensive overview of the different stratigraphic units, starting from the oldest and ending with the youngest. Modern stratigraphic schemes highlight formations’ geometries and interrelations. Some of the most remarkable units are further detailed. The two orogenic phases that shaped the Lower Paleozoic inliers and the Devonian-Carboniferous faulted and folded belt, i.e. the Caledonian and Variscan orogeny, are also addressed. [less ▲]

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See detailSedimentologic and paleoclimatic reconstructions of carbonate factory evolution in the Alborz Basin (northern Iran) indicate a global response to Early Carboniferous (Tournaisian) glaciations
Sardar Abadi, Mehrdad; Kulagina, E.; Voeten, D.F.A.E. et al

in Sedimentary Geology (2017), 348

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See detailDetailed characterization of the Late Pleistocene loess sequence stratigraphy of Remicourt (Hesbaye region, Belgium) with cone penetration tests
Delvoie, Simon ULiege; Boulvain, Frédéric ULiege; Charlier, Robert ULiege et al

in Geologica Belgica (2016), 19(3-4), 281-289

Cone penetration tests (CPT) and drilling results are used to characterize the Middle Belgium loess sequence. A two scale study has been realized in the Hesbaye region (Belgium). The study on a regional ... [more ▼]

Cone penetration tests (CPT) and drilling results are used to characterize the Middle Belgium loess sequence. A two scale study has been realized in the Hesbaye region (Belgium). The study on a regional scale was performed along a 18 km long section of the high-speed railway Liège-Brussels. About 230 tests were compiled. Results show the loess thickness is very variable and can locally reach 20 m. Tertiary deposits become continuous and they rapidly thicken from Waremme to the West. The lower surface of the Tertiary deposits is characterized by a 0.3% apparent dipping to the NW. The dipping likely results from the Ardenne Massif uplift. The local scale study focuses on the site of Remicourt located along the high-speed railway. 24 CPT tests have been carried out very close to a series of archaeological trenches. The analysis shows penetrometers are able to define some stratigraphic markers within the loess layer. The most identifiable marker is stratigraphically located around the transition between the Humiferous Complex of Remicourt and the Rocourt Pedocomplex. The lens-shape of the loess ridge is also confirmed by the penetrometers’ interpretation. Furthermore, the 3D morphology of each stratigraphic marker can be estimated. These results offer interesting perspectives for the investigation of the loess sequence related to archaeological applications. [less ▲]

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See detailGeochemistry of Lower Devonian terrigenous sedimentary rocks from the Belgian Ardenne: Source proxy and paleogeographic reconstruction
Duchesne, Jean-Clair ULiege; Boulvain, Frédéric ULiege

Poster (2016, July 04)

Major and trace element (Rb, Sr, Ba, Zr, Ni, V, Zn, Cr, Y, Ce) compositions are studied in Lower Devonian terrigenous sediments from the Dinant Synclinorium and Ardenne Anticline (Belgian Ardenne). Five ... [more ▼]

Major and trace element (Rb, Sr, Ba, Zr, Ni, V, Zn, Cr, Y, Ce) compositions are studied in Lower Devonian terrigenous sediments from the Dinant Synclinorium and Ardenne Anticline (Belgian Ardenne). Five cross sections encompassing 148 samples in19 formations have been studied. In the conventional [Al2O3+Fe2O3-K2O-Na2O]–[K2O]–[FeO+MgO] triangle, the rock compositions plot on the illite – chlorite tie line. This suggests that (1) the mineral association has reached equilibrium in the pressure and temperature range of the postdepositional evolution of the sediments; (2) the chemical system was open and K was a mobile component. Although the original composition of the sediment was modified, the AAFM = Al2O3/Al2O3+FeOt+MgO parameter that reflects the illite - chlorite proportions can be used as a proxy of the source composition. A principal component analysis of the major and trace element compositions permits to define the behaviour of various elements currently used as proxies of various processes. Noteworthy it is shown that Ti, V and part of Cr are correlated with the illite proportion and part of Cr, together with Zr, with resistate minerals such as quartz, chromite and zircon. The evolution with stratigraphic age in the 5 cross sections of the AAFM proxy reveals that there is a major change in the northern part of the Ardenne Anticline at the limit between the Mirwart Formation and younger formations, corresponding approximately to the Lochkovian to Pragian transition. There is a clear shift from an aluminium-rich source to a more conventional chlorite-rich source. In the paleogeographic evolution of this region the only possible source of the aluminium-rich sediment is the Rocroi Massif. This conclusion confirms sedimentological and palynological evidence that a “Rocroi Island” existed in the Lochkovian Sea. A decrease in Zr concentrations with distance to the Rocroi Massif also supports this hypothesis. The stratigraphic evolution of several parameters shows local variations that can be attributed to variable streams and depositional conditions in an alluvial deltaic or shallow sea environment. [less ▲]

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See detailReappraisal of the deep Devonian strata under the Mons Basin
Licour, L.; Dupont, N.; Swennen, R. et al

Conference (2016, January)

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See detailÉvolution des séries silicoclastiques miocènes en Tunisie centrale : Cas de la coupe de Khechem El Artsouma
Belghithi, Hanen ULiege; Boulvain, Frédéric ULiege; Chokri, Yaich et al

in Carnets de Géologie = Notebooks on Geology (2016), 16(23), 557-568

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See detailGeoheritage in Ardennes (France and Belgium): geology, cultural heritage and landscapes
Fronteau, Gilles; Yans, Johan; Boulvain, Frédéric ULiege et al

in Mémoire hors série de la Société géologique de France (2016), 16

The geology of the Western part of the Ardenne Massif is renowned by various stratotypical outcrops. But the Ardennes, highlighted with the geoheritage point of view, can show other specific topics. Some ... [more ▼]

The geology of the Western part of the Ardenne Massif is renowned by various stratotypical outcrops. But the Ardennes, highlighted with the geoheritage point of view, can show other specific topics. Some of these topics are based on geomaterials: the slates from the Cambrian formations, the ancient millstones quarries in lower Devonian sandstones, the red "marbles" and blue or black ornamental limestones from middle and upper Devonian, the fluorine deposits... Others are focused on geomorphological specific sites, linked to local legends. These sites, sometimes already included in the touristic promotion of the Ardennes, can be an excellent entry point to encourage the emergence of a transnational Geopark project in this area. [less ▲]

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See detailLe phénomène récifal Givétien en Ardenne
Boulvain, Frédéric ULiege; Mabille, Cédric; Da Silva, Anne-Christine ULiege

in Brice, Denise (Ed.) Stratotype Givétien (2016)

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See detailL'état actuel du stratotype
Brice, Denise; Boulvain, Frédéric ULiege; Hubert, Benoït et al

in Brice, Denise (Ed.) Stratotype Givétien (2016)

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See detailLes sites remarquables
BRICE, Denise; Boulvain, Frédéric ULiege; Hubert, Benoît et al

in Brice, Denise (Ed.) Stratotype Givétien (2016)

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See detailInsights into a million-year-scale Rhenohercynian carbonate platform evolution through a multi-disciplinary approach: example of a GIvetian carbonate record from Belgium
Pas, Damien ULiege; Da Silva, Anne-Christine ULiege; Devleeschouwer, Xavier et al

Poster (2016)

In this study we formulate answers to three important questions related to Givetian carbonate records and their use for reconstructing million-year past palaeoenvironmental changes. First, we provide ... [more ▼]

In this study we formulate answers to three important questions related to Givetian carbonate records and their use for reconstructing million-year past palaeoenvironmental changes. First, we provide detailed illustrations of the fascinating depositional diversity that shaped a shallow reefal platform during the early- to late-Givetian in the Rhenohercynian Ocean; secondly we improve the sedimentological model of the Givetian carbonate platform in the Dinant Basin (Belgium) and thirdly we evaluate the application of magnetic susceptibility (MS) as a tool for long-term trends, correlation, and palaeoenvironmental reconstruction. These three goals are reached by making a detailed sedimentological, geophysical and geochemical study of the La Thure quarry. Petrographic analyses revealed eighteen microfacies which represent a carbonate platform evolution through early-late Givetian time, ranging from a homoclinal ramp to a discontinuously rimmed shelf and then a drowning shelf. These results allowed us to illustrate the fascinating environmental diversity that shaped one the largest carbonate platforms of Europe and provide an up to date model of the vertical and lateral development of the Belgian Givetian platform. Early-late Givetian La Thure sequence reveals five main depositional intervals, which could be correlated with the southern margin of the platform. These correlations allowed us to define the facies belts distribution, the major depositional changes that affected this platform and to highlight the Taghanic Event. Palaeo-redox proxies reveal a significant change in the oxygenation level, from oxygen-depleted to more oxic condition, between middle and late Givetian. This change is well-correlated with an increase in global temperature in the late Mid Devonian. Combination of MS and geochemistry demonstrates the inherent-parallel link existing between variation in MS values and proxies for siliciclastic input (such as Si, Al). Collected geochemical and MS data confirm that the La Thure can be considered as a key section for the internal shelf setting in the Rhenohercynian Ocean bordering Laurussia’s south-eastern margin. [less ▲]

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See detailPierres et marbres en Wallonie: reconnaissance et genèse
Boulvain, Frédéric ULiege; Tourneur, Francis ULiege

Book published by Académie royale de Belgique (2015)

Chacun a eu dans sa maison, sous forme de dalles, cheminées, bibelots, des pierres et marbres. Ces matériaux se sont formés dans des milieux variés, souvent des mers peu profondes et sont les témoins de ... [more ▼]

Chacun a eu dans sa maison, sous forme de dalles, cheminées, bibelots, des pierres et marbres. Ces matériaux se sont formés dans des milieux variés, souvent des mers peu profondes et sont les témoins de près d’un demi-milliard d’années d’histoire de notre région! Cette richesse géologique représente aussi une fabuleuse richesse archéologique et patrimoniale dans l’utilisation exceptionnellement variée qui en a été faite, depuis l’époque romaine jusqu’à nos jours. Donner à chacun l’occasion d’identifier et de comprendre ces pierres et marbres est le but de ce livre. [less ▲]

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See detailSILURIAN – DEVONIAN BLACK SHALES IN THE ORIENTAL ALGERIAN SAHARA: implication of new field data from Tassili n'Ajjer outcrops and Berkine Basin (SE, Algeria).
Djouder, Hocine ULiege; Boulvain, Frédéric ULiege; Da Silva, Anne-Christine ULiege et al

Scientific conference (2015, November)

The Silurian (Llandovery) and the Devonian (Frasnian) are a periods of interest because sediments and organic-rich shales were deposited in many places that form important hydrocarbon reservoirs and ... [more ▼]

The Silurian (Llandovery) and the Devonian (Frasnian) are a periods of interest because sediments and organic-rich shales were deposited in many places that form important hydrocarbon reservoirs and source rocks throughout North Africa basins and Middle East (Boot et al., 1998 ; Lüning et al., 2000). These organic-rich shales lead Algeria to hold the fourth position in terms of the estimates of technically recoverable shale oil and shale gas resources, based on major basin assessment in the world (EIA, 2013). In the prolific Illizi and Berkine basins (western Ghadames, Algeria) a basin-wide approach is needed, especially with the new “shale gas and shale oil” frontier in the upcoming years, in order to capture regional trends and re-assessment the Siluro-Devonian successions. Wireline-logs from more than 146 (Berkine – Illizi Basin) Algerian petroleum exploration wells have been studied (Djouder et al., 2012; Djouder et al., 2014). In addition, a complete logging of spectacular large-scale and well exposed outcrops of the Siluro-Devonian sediments was carried out at the south margin (SE, Tassili n’Ajjer) of the Illizi-Berkine basins. The following analysis incorporates biostratigraphic, ichnological, sedimentological, magnetic susceptibility and high resolution stratigraphic data. It would allow providing a framework of deposits, ranging from offshore to deltaic deposits for the Silurian and from fluvial to normal-marine depositional conditions for the Devonian. References cited: Boote, D.R.D., Clark-Lowes, D.D., Traut, M.W., 1998. Palaeozoic petroleum systems of North Africa. In: Macgregor, D.S., Moo- dy, R.T.J., Clark-Lowes, D.D. (Eds.), Petroleum Geology of North Africa. Geol. Soc. London Sp. Publ., vol. 132, pp. 7–68. Lüning, S., Craig, J., Loydell, D.K., Štorch, P., Fitches, B., 2000. Lower Silurian ‘hot shales’ in North Africa and Arabia: regional distribution and depositional model. Earth-Science Reviews, 121-200. EIA – U.S. Energy Information Administration, 2013. Technically Recoverable Shale Oil and Shale Gas Resources: An Assessment of 137 Shale Formations in 41 Countries Outside the United States. Rapport de 730 p. Djouder, H., Pagel, M., Murat, B., Orsingher, M., 2012. Le Silurien du Bassin de Berkine. Projet « Shale Gas » Profond. 10éme Colloque du Groupe Français des Argiles, Présentation Orale, Limoge, France 14-18 Mai 2012. http://hdl.handle.net/2268/171556 Djouder, H., Boulvain, F., Da Silva, A-C., Cornet, P., Lüning, S., 2014. Tassili n’Ajjer (Sahara Oriental Algérien) – Résultats préliminaires sur le Silurien – Dévonien : Journée Thématique de l’Association des Sédimentologistes Français (ASF) – Diagenèse : avancées récentes et perspectives, Présentation Poster, Orsay-Paris, France 04 Juillet 2014. http://hdl.handle.net/2268/171557 [less ▲]

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See detailSILURIAN – DEVONIAN OF THE ORIENTAL ALGERIAN SAHARA: implication of new field data from Tassili n'Ajjer outcrops and Berkine Basin (SE, Algeria) for shale gas exploration.
Djouder, Hocine ULiege; Boulvain, Frédéric ULiege; Da Silva, Anne-Christine ULiege et al

in EPC'2015 THE THIRTEENTH TUNISIAN PETROLEUM EXPLORATION & PRODUCTION CONFERENCE (2015, October)

The Silurian – Devonian succession have been deposited in wide sags and sub-basins in a cratonic setting, along the northwestern passive margin of the Gondwana during the opening of the proto-Tethyan ... [more ▼]

The Silurian – Devonian succession have been deposited in wide sags and sub-basins in a cratonic setting, along the northwestern passive margin of the Gondwana during the opening of the proto-Tethyan ocean. During this Siluro-Devonian Period, a high subsidence occurs stacked sediment bodies and organic-rich shales were deposited in many places that respectively form important hydrocarbon reservoirs and source rocks throughout North Africa basins and Arabia (Boot et al., 1998 ; Lüning et al., 2000), which lead Algeria to hold the fourth position in terms of the estimates of technically recoverable shale oil and shale gas resources, based on major basin assessment in the world (EIA, 2013). In the prolific Illizi and Berkine basins (western Ghadames, Algeria) a basin-wide approach is needed, especially with the new “shale gas and shale oil” frontier in the upcoming years, in order to capture regional trends and re-assessment on organic-rich (‘hot’) shale unites which in smaller-scale industrial studies are overlooked. Berkine Basin covers nearly 102.000 km2. This basin has been a thick sedimentary series of 7000 m corresponding to complex reservoirs but also black shales of the basal Silurian and Frasnian respectively major and secondary source rock systems. Wireline-logs from more than 146 (Berkine – Illizi Basins) Algerian petroleum exploration wells have been studies (Djouder et al., 2012; Djouder et al., 2014), and recently 03 months extensive field study of outcrops of the Siluro-Devonian sediments was carried out at the south margin (SE, Tassili n’Ajjer) of the basin. The following analysis incorporates biostratigraphic, ichnological, sedimentological and high resolution stratigraphic data, which provides a framework evolution from offshore to deltaic deposition for the Silurian then fluvial to normal-marine depositional conditions for the Devonian. A total of 06 short-term, third-order sequences can be identified for the Silurian deposits: (i) 'Hot Shale' Oued Imihrou Formation, organic-rich shales with carbonates nodules (Si-1); (ii) above is the Atafaïtafa Formation 500 to 650 m thick with HCS, gutter casts and Cruziana Ichnofacies (Si-2, Si-3); (iii) then overlaid by coarsening-shallowing-upward units. These sequences (Si-4, Si-5 & Si-6) with Storm-wave dominated and Skolithos Ichnofacies are interpreted to reflect deltaic origin. This delta is the result of a significant sea-level drop during the Upper Silurian (Beuf et al, 1971) but also from the high sedimentation rates prograding northwards (Eschard et al., 2005). Devonian deposit also can be divided into fourth third-order sequences (Dev-1 to 4), by the same previous analysis. The base of the cycle is the Caledonian unconformity linked to a tectonic event which affected most of the Gondwanan margin at the Silurian – Devonian boundary and a major relative sea-level fall (Eschard et al., 2005). Previous sequences defined from Tassili n’Ajjer outcrops are well recognized at the basin-scale (Berkine Basin) and can be correlated in the subsurface of the Illizi – Berkine basins (Djouder et al., 2012). Finally, the full depositional cycle for the Silurian – Devonian is reached and capped by the Frasnian maximum flooding surface, with black shales across North Africa (Algeria, western Libya and southern Tunisia) and which are also developed in many parts of the world (Lüning et al., 2003). [less ▲]

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