The Bou Dahar Pb–Zn–Ba (±Sr) is hosted in the Lower and Middle Liassic carbonate platform in the ... more The Bou Dahar Pb–Zn–Ba (±Sr) is hosted in the Lower and Middle Liassic carbonate platform in the oriental High Atlas of Morocco. The paragenetic sequence includes quartz–pyrite–melnicovite–sphalerite–galena– calcite–barite ± fluorite– ± celestite. Fluid-inclusion studies were conducted on sphalerite (early mineralizing stage) and barite, and celestite (late mineralizing stage). These studies reveal two end-member fluids, a hot (~143 °C) and saline fluid (~23 wt.% NaCl eq.) and a cooler (b50 °C) and diluted fluid (~5 wt.% NaCl eq.). Based on fluid-inclusion and C–O–S isotope studies, a conclusion is reached that the Bou Dahar ore deposits were formed by the mixing of two fluid — a diluted, SO2−4-rich fluid, and an 18O-enriched basinal brine that car- ried Pb, Zn, and Ba. The sulfur required for the precipitation of sulfides was generated by the thermochemical sul- fate reduction of dissolved sulfate (SO24−) of the Mesozoic seawaters, and delivered to the site of ore deposition. The sulfur of sulfate minerals was derived directly from these dissolved SO24. The Pb isotope compositions are ho- mogenous with 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios ranging from 18.124 to 18.183, 15.630 to 15.634, and 38.325 to 38.440 respectively. This Pb isotope composition is indicative of an upper crust and orogene reser- voirs as the source of lead and other metals. The emplacement of mineralization occurred during the Eocene– Miocene Alpine orogeny, and tectonic burial and compression were the driving forces behind the circulation of the orogenic-brines. These ore-forming fluids migrated, along thrusting regional E–W and NE–SW deep-seated faults, to the confined carbonate-Liassic reservoir.
Petrolographical and sedimentological studies of the Ain Mimoun Albian sediments Khenchela anticl... more Petrolographical and sedimentological studies of the Ain Mimoun Albian sediments Khenchela anticline) show that the upper Aptian (Clansayesian) is an incomplete sedimentary cycle. The latter ends with an emersion phase and is separated from the first ...
... Auteur(s) / Author(s). GUILHAUMOU N. (1) ; TOURAY J.-C. ; SALAH BOUHLEL ; Affiliation(s) du o... more ... Auteur(s) / Author(s). GUILHAUMOU N. (1) ; TOURAY J.-C. ; SALAH BOUHLEL ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). (1) Ecole normale supérieure, Paris 75230, FRANCE Revue / Journal Title. Bulletin de minéralogie ISSN 0180-9210 CODEN BULMD9 ...
The biostratigraphical study, based on the calpionellids and foraminifera, of the Jurassic-Cretac... more The biostratigraphical study, based on the calpionellids and foraminifera, of the Jurassic-Cretaceous boundary in the sector of Hammam Zriba-Guebli (Northern Tunisia), leads to precise the age and facies of ante-Campanian limestones. These limestones, which characterize pelagic facies in the Jebel Guebli cross section, were attributed to the Tithonian. In this study, the recorded calpionellids allowed us to give an upper Tithonian, Berriasian and lower Valanginian age. In the Hammam Zriba cross section (1 km northern side) the neritic facies rich in algae and benthic foraminifera characterize the Jurassic-Cretaceous boundary. The juxtaposition of these two facies shows a horsts and half grabens structuration characterizing Jurassic-Cretaceous boundary in this sector. The Campanian transgressive limestone has provided planctonic foraminifera with Globotruncana genus characterizing lower to upper Campanian. Résumé: L'étude biostratigraphique basée sur les calpionelles et les foram...
Carthage punique diffusion et permanence de sa culture en Afrique antique 15 Boutheina MARAOUI TE... more Carthage punique diffusion et permanence de sa culture en Afrique antique 15 Boutheina MARAOUI TELMINI 1 , Jaloul BÉJAOUI 2 , Haïfa BEN ABDELOUAHED 3 , Salah BOUHLEL 4 CONTRIBUTION À LA CARACTÉRISATION MINÉRALOGIQUE, PÉTROGRAPHIQUE ET CHIMIQUE DE LA CÉRAMIQUE PUNIQUE COMMUNE DE CARTHAGE ET DES ARGILES DE LA RÉGION I-INTRODUCTION : (B. Maraoui Telmini) Des investigations scientifiques 5 , menées sur des échantillons de céramique punique de Carthage, permirent à P. Cintas de conclure en 1950, à « …une très grande analogie des compositions chimiques des terres entraînant une présomption d'origine commune de l'argile utilisée aux différentes époques…les différences de structure importantes révélées par les rayons X doivent être attribuées à des différences dans la technique de la cuisson» 6 . Plus récemment, des recherches archéométriques effectuées sur des échantillons de vases ouverts à engobe rouge de Carthage 7 parviennent à la distinction de deux types d'argile utilisés...
The principal aim of this work is to study a hydrothermal system of the epigenetic Pb-Zn-Ba depos... more The principal aim of this work is to study a hydrothermal system of the epigenetic Pb-Zn-Ba deposits generally hosted in platform carbonate succession of lower cretaceous age in Jebel El Hamra (Fig. 1) in Central Tunisia, the deposit have been studied by ...
Abstract The Sekarna Zn–Pb deposit is located in Central Tunisia at the northeastern edge of the ... more Abstract The Sekarna Zn–Pb deposit is located in Central Tunisia at the northeastern edge of the Cenozoic Rohia graben. Mineralization comprises two major ore types:(1) disseminated Zn–Pb sulfides that occur as lenses in sedimentary phosphorite layers and ( ...
ABSTRACT The Jebel Hamra, which is hosted in the Graben Zone of central Tunisia, is an epigenetic... more ABSTRACT The Jebel Hamra, which is hosted in the Graben Zone of central Tunisia, is an epigenetic dolomite-hosted PbZnBa deposit that replaces platform carbonates of Lower Cretaceous age (Upper Aptian). Mineralization occurs as stratiform lenses, and breccia- and paleokarst-fillings. Ore reserves are around 0.5 Mt and grades are 7% Zn and 3% Pb. Sulphide mineralization occurs as local replacement of dolomitized and silicified carbonate strata. Primary inclusion fluids in sphalerite have homogenization temperatures ranging from 110 to 152 °C with a mode at 137 °C. Final ice-melting temperatures range from − 15 to − 10 °C, corresponding to salinities of 13.5–18.5 wt.% NaCl equiv. Fluid inclusions in saddle dolomite homogenize to the liquid phase between 175°C and 193 °C, with a mode at 187 °C. Final ice-melting temperatures range from − 23 to − 15 °C corresponding to salinities between 18 and 24 wt.% NaCl equiv. δ34S values of sphalerite and galena vary between − 3 and + 6.3‰, compatible with a thermochemical reduction of sulfate from Triassic evaporites (δ34S = + 15‰). PbZnBa mineralization is spatially and possibly genetically related to E–W-trending fractures, which acted as conduits and/or depositional sites for circulating hydrothermal fluids. Fluid inclusion and sulfur isotope data suggest the contribution of basinal brines in ore formation. Combined field, sedimentological, mineralogical, isotopic and geochemical data of the Lower Cretaceous mineralization in Jebel Hamra is compatible with Mississippi-Valley-type mineralization.
This study attempts to determine if there was Roman lead mining in Africa Proconsularis, approxim... more This study attempts to determine if there was Roman lead mining in Africa Proconsularis, approximately the area of modern day Tunisia, using lead isotope analysis. Another important aspect of the study is the innovative use of electron microprobe analysis (EMPA) ...
ABSTRACT Laser ablation ICP-MS was used to determine trace (TE) and rare earth element (REE) cont... more ABSTRACT Laser ablation ICP-MS was used to determine trace (TE) and rare earth element (REE) contents of sedimentary phosphatic pellets and coprolites collected from late Paleocene-early Eocene phosphorite deposits in Tunisia. TE and REE contents in the investigated deposits exhibit a close relationship with grain types and paleogeography. Phosphatic pellets seem to concentrate more TE and REE than co-existing coprolites. Both particle types display modern oxic-suboxic seawater patterns. In most coprolites, ∑REE, Y, Cr, Ni, Th, and V show an increase from core to rim, whereas Ba, Cd, Cu, and U abundances decrease from core to rim, reflecting adsorption processes during early diagenesis consistent with changing redox and productivity conditions.The northern basins (Sra Ouertane) within open marine and platform settings tended to be more oxic-suboxic with relative high organic matter flux, while the eastern basins (Jebel Jebs) and Gafsa-Metlaoui basin are characterized by semi-restricted situation associated with suboxic-oxic conditions. This result is consistent with previous reconstructions which suggest that phosphorites of northern basins had a more direct connection to the open ocean than those to the south and east of the emerged area.This study highlights the potential for using laser ablation ICP-MS as a tool to reconstruct phosphorite depositional paleoenvironments.
Abstract In this study we investigate the radiological hazard of naturally occurring radioactive ... more Abstract In this study we investigate the radiological hazard of naturally occurring radioactive material in Tunisian and Algerian phosphorite deposits. Eight samples of phosphorite were collected from the phosphorite mines. The Tunisian and Algerian phosphorites occur in the Late Paleocene and Lower Eocene (Ypresian-Lutetian) in age (Béji Sassi 1984 and Zaïer 1999). Activity concentrations in all the samples were measured by alpha spectrometry and gamma spectrometry. Alpha spectrometry analyses show that the specific activity values of ...
ABSTRACT The Oued Jebs Pb–Zn–Sr deposit is situated on the south edge of the Mourra Triassic diap... more ABSTRACT The Oued Jebs Pb–Zn–Sr deposit is situated on the south edge of the Mourra Triassic diapir, in the Diapir Zone of the Tunisian Atlas. Tow orebody-type are recognized: (1) lens-chapped orebodies hosted in the Dolomitic cap rock that marks the transition zone between the Triassic gypsum cap rock and the overlaying Late Cretaceous series. Mineralization is composed of epigenetic celestite and minor Pb–Zn sulfides. (2) Vein-type and massive-type orebodies crosscutting the Late Cenomanian and Turonian limestone. Mineralization is composed of high-grade ore ranging from 10 to 25 % combined Pb–Zn. Fluid inclusion data for celestite indicate that deposition took place between 70 and 100 °C, or more cooler conditions as indicated by the presence of single-phase inclusions, from mixed NaCl–CaCl2-bearing brines (12–19 wt% NaCl equiv). For the vein-type and massive-type fluid inclusion, data recorded in sphalerite indicate that sulfide deposition took place between 125 and 130 °C mixed NaCl–CaCl2-bearing brines (10–15 wt% NaCl equiv). At least three dilution and cooling trends are also observed that indicate the involvement of more than one fluid in the Oued Jebs hydrothermal system. The epigenetic character of the ores, the host rock nature and the fluid inclusion together permitted to include the Oued Jebs deposit in the large class of MVT deposits and preciously in the sub-class of MVTs associated with salt diapirs environment. The new discovered Oued Jebs deposit is similar in many aspects to the economic Bou Grine deposit. This may point to significant other potential for economic Pb–Zn concentrations that may be located at depth alongside or above many other unexplored Triassic diapirs in the Diapirs zone of the Tunisian Atlas.
The Bou Dahar Pb–Zn–Ba (±Sr) is hosted in the Lower and Middle Liassic carbonate platform in the ... more The Bou Dahar Pb–Zn–Ba (±Sr) is hosted in the Lower and Middle Liassic carbonate platform in the oriental High Atlas of Morocco. The paragenetic sequence includes quartz–pyrite–melnicovite–sphalerite–galena– calcite–barite ± fluorite– ± celestite. Fluid-inclusion studies were conducted on sphalerite (early mineralizing stage) and barite, and celestite (late mineralizing stage). These studies reveal two end-member fluids, a hot (~143 °C) and saline fluid (~23 wt.% NaCl eq.) and a cooler (b50 °C) and diluted fluid (~5 wt.% NaCl eq.). Based on fluid-inclusion and C–O–S isotope studies, a conclusion is reached that the Bou Dahar ore deposits were formed by the mixing of two fluid — a diluted, SO2−4-rich fluid, and an 18O-enriched basinal brine that car- ried Pb, Zn, and Ba. The sulfur required for the precipitation of sulfides was generated by the thermochemical sul- fate reduction of dissolved sulfate (SO24−) of the Mesozoic seawaters, and delivered to the site of ore deposition. The sulfur of sulfate minerals was derived directly from these dissolved SO24. The Pb isotope compositions are ho- mogenous with 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios ranging from 18.124 to 18.183, 15.630 to 15.634, and 38.325 to 38.440 respectively. This Pb isotope composition is indicative of an upper crust and orogene reser- voirs as the source of lead and other metals. The emplacement of mineralization occurred during the Eocene– Miocene Alpine orogeny, and tectonic burial and compression were the driving forces behind the circulation of the orogenic-brines. These ore-forming fluids migrated, along thrusting regional E–W and NE–SW deep-seated faults, to the confined carbonate-Liassic reservoir.
Petrolographical and sedimentological studies of the Ain Mimoun Albian sediments Khenchela anticl... more Petrolographical and sedimentological studies of the Ain Mimoun Albian sediments Khenchela anticline) show that the upper Aptian (Clansayesian) is an incomplete sedimentary cycle. The latter ends with an emersion phase and is separated from the first ...
... Auteur(s) / Author(s). GUILHAUMOU N. (1) ; TOURAY J.-C. ; SALAH BOUHLEL ; Affiliation(s) du o... more ... Auteur(s) / Author(s). GUILHAUMOU N. (1) ; TOURAY J.-C. ; SALAH BOUHLEL ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). (1) Ecole normale supérieure, Paris 75230, FRANCE Revue / Journal Title. Bulletin de minéralogie ISSN 0180-9210 CODEN BULMD9 ...
The biostratigraphical study, based on the calpionellids and foraminifera, of the Jurassic-Cretac... more The biostratigraphical study, based on the calpionellids and foraminifera, of the Jurassic-Cretaceous boundary in the sector of Hammam Zriba-Guebli (Northern Tunisia), leads to precise the age and facies of ante-Campanian limestones. These limestones, which characterize pelagic facies in the Jebel Guebli cross section, were attributed to the Tithonian. In this study, the recorded calpionellids allowed us to give an upper Tithonian, Berriasian and lower Valanginian age. In the Hammam Zriba cross section (1 km northern side) the neritic facies rich in algae and benthic foraminifera characterize the Jurassic-Cretaceous boundary. The juxtaposition of these two facies shows a horsts and half grabens structuration characterizing Jurassic-Cretaceous boundary in this sector. The Campanian transgressive limestone has provided planctonic foraminifera with Globotruncana genus characterizing lower to upper Campanian. Résumé: L'étude biostratigraphique basée sur les calpionelles et les foram...
Carthage punique diffusion et permanence de sa culture en Afrique antique 15 Boutheina MARAOUI TE... more Carthage punique diffusion et permanence de sa culture en Afrique antique 15 Boutheina MARAOUI TELMINI 1 , Jaloul BÉJAOUI 2 , Haïfa BEN ABDELOUAHED 3 , Salah BOUHLEL 4 CONTRIBUTION À LA CARACTÉRISATION MINÉRALOGIQUE, PÉTROGRAPHIQUE ET CHIMIQUE DE LA CÉRAMIQUE PUNIQUE COMMUNE DE CARTHAGE ET DES ARGILES DE LA RÉGION I-INTRODUCTION : (B. Maraoui Telmini) Des investigations scientifiques 5 , menées sur des échantillons de céramique punique de Carthage, permirent à P. Cintas de conclure en 1950, à « …une très grande analogie des compositions chimiques des terres entraînant une présomption d'origine commune de l'argile utilisée aux différentes époques…les différences de structure importantes révélées par les rayons X doivent être attribuées à des différences dans la technique de la cuisson» 6 . Plus récemment, des recherches archéométriques effectuées sur des échantillons de vases ouverts à engobe rouge de Carthage 7 parviennent à la distinction de deux types d'argile utilisés...
The principal aim of this work is to study a hydrothermal system of the epigenetic Pb-Zn-Ba depos... more The principal aim of this work is to study a hydrothermal system of the epigenetic Pb-Zn-Ba deposits generally hosted in platform carbonate succession of lower cretaceous age in Jebel El Hamra (Fig. 1) in Central Tunisia, the deposit have been studied by ...
Abstract The Sekarna Zn–Pb deposit is located in Central Tunisia at the northeastern edge of the ... more Abstract The Sekarna Zn–Pb deposit is located in Central Tunisia at the northeastern edge of the Cenozoic Rohia graben. Mineralization comprises two major ore types:(1) disseminated Zn–Pb sulfides that occur as lenses in sedimentary phosphorite layers and ( ...
ABSTRACT The Jebel Hamra, which is hosted in the Graben Zone of central Tunisia, is an epigenetic... more ABSTRACT The Jebel Hamra, which is hosted in the Graben Zone of central Tunisia, is an epigenetic dolomite-hosted PbZnBa deposit that replaces platform carbonates of Lower Cretaceous age (Upper Aptian). Mineralization occurs as stratiform lenses, and breccia- and paleokarst-fillings. Ore reserves are around 0.5 Mt and grades are 7% Zn and 3% Pb. Sulphide mineralization occurs as local replacement of dolomitized and silicified carbonate strata. Primary inclusion fluids in sphalerite have homogenization temperatures ranging from 110 to 152 °C with a mode at 137 °C. Final ice-melting temperatures range from − 15 to − 10 °C, corresponding to salinities of 13.5–18.5 wt.% NaCl equiv. Fluid inclusions in saddle dolomite homogenize to the liquid phase between 175°C and 193 °C, with a mode at 187 °C. Final ice-melting temperatures range from − 23 to − 15 °C corresponding to salinities between 18 and 24 wt.% NaCl equiv. δ34S values of sphalerite and galena vary between − 3 and + 6.3‰, compatible with a thermochemical reduction of sulfate from Triassic evaporites (δ34S = + 15‰). PbZnBa mineralization is spatially and possibly genetically related to E–W-trending fractures, which acted as conduits and/or depositional sites for circulating hydrothermal fluids. Fluid inclusion and sulfur isotope data suggest the contribution of basinal brines in ore formation. Combined field, sedimentological, mineralogical, isotopic and geochemical data of the Lower Cretaceous mineralization in Jebel Hamra is compatible with Mississippi-Valley-type mineralization.
This study attempts to determine if there was Roman lead mining in Africa Proconsularis, approxim... more This study attempts to determine if there was Roman lead mining in Africa Proconsularis, approximately the area of modern day Tunisia, using lead isotope analysis. Another important aspect of the study is the innovative use of electron microprobe analysis (EMPA) ...
ABSTRACT Laser ablation ICP-MS was used to determine trace (TE) and rare earth element (REE) cont... more ABSTRACT Laser ablation ICP-MS was used to determine trace (TE) and rare earth element (REE) contents of sedimentary phosphatic pellets and coprolites collected from late Paleocene-early Eocene phosphorite deposits in Tunisia. TE and REE contents in the investigated deposits exhibit a close relationship with grain types and paleogeography. Phosphatic pellets seem to concentrate more TE and REE than co-existing coprolites. Both particle types display modern oxic-suboxic seawater patterns. In most coprolites, ∑REE, Y, Cr, Ni, Th, and V show an increase from core to rim, whereas Ba, Cd, Cu, and U abundances decrease from core to rim, reflecting adsorption processes during early diagenesis consistent with changing redox and productivity conditions.The northern basins (Sra Ouertane) within open marine and platform settings tended to be more oxic-suboxic with relative high organic matter flux, while the eastern basins (Jebel Jebs) and Gafsa-Metlaoui basin are characterized by semi-restricted situation associated with suboxic-oxic conditions. This result is consistent with previous reconstructions which suggest that phosphorites of northern basins had a more direct connection to the open ocean than those to the south and east of the emerged area.This study highlights the potential for using laser ablation ICP-MS as a tool to reconstruct phosphorite depositional paleoenvironments.
Abstract In this study we investigate the radiological hazard of naturally occurring radioactive ... more Abstract In this study we investigate the radiological hazard of naturally occurring radioactive material in Tunisian and Algerian phosphorite deposits. Eight samples of phosphorite were collected from the phosphorite mines. The Tunisian and Algerian phosphorites occur in the Late Paleocene and Lower Eocene (Ypresian-Lutetian) in age (Béji Sassi 1984 and Zaïer 1999). Activity concentrations in all the samples were measured by alpha spectrometry and gamma spectrometry. Alpha spectrometry analyses show that the specific activity values of ...
ABSTRACT The Oued Jebs Pb–Zn–Sr deposit is situated on the south edge of the Mourra Triassic diap... more ABSTRACT The Oued Jebs Pb–Zn–Sr deposit is situated on the south edge of the Mourra Triassic diapir, in the Diapir Zone of the Tunisian Atlas. Tow orebody-type are recognized: (1) lens-chapped orebodies hosted in the Dolomitic cap rock that marks the transition zone between the Triassic gypsum cap rock and the overlaying Late Cretaceous series. Mineralization is composed of epigenetic celestite and minor Pb–Zn sulfides. (2) Vein-type and massive-type orebodies crosscutting the Late Cenomanian and Turonian limestone. Mineralization is composed of high-grade ore ranging from 10 to 25 % combined Pb–Zn. Fluid inclusion data for celestite indicate that deposition took place between 70 and 100 °C, or more cooler conditions as indicated by the presence of single-phase inclusions, from mixed NaCl–CaCl2-bearing brines (12–19 wt% NaCl equiv). For the vein-type and massive-type fluid inclusion, data recorded in sphalerite indicate that sulfide deposition took place between 125 and 130 °C mixed NaCl–CaCl2-bearing brines (10–15 wt% NaCl equiv). At least three dilution and cooling trends are also observed that indicate the involvement of more than one fluid in the Oued Jebs hydrothermal system. The epigenetic character of the ores, the host rock nature and the fluid inclusion together permitted to include the Oued Jebs deposit in the large class of MVT deposits and preciously in the sub-class of MVTs associated with salt diapirs environment. The new discovered Oued Jebs deposit is similar in many aspects to the economic Bou Grine deposit. This may point to significant other potential for economic Pb–Zn concentrations that may be located at depth alongside or above many other unexplored Triassic diapirs in the Diapirs zone of the Tunisian Atlas.
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