The mining district of Nefza-Sejnane (Tunisia) encloses numerous ores and raw material deposits, ... more The mining district of Nefza-Sejnane (Tunisia) encloses numerous ores and raw material deposits, all formed in relation with successive Fe-rich fluids of meteoric and/or hydrothermal origins. Here, for the first time in Tunisia, (U-Th)/He ages were obtained on supergene goethite from various localities/deposits of the district highlight direct dating of significant weathering episodes during late Tortonian and late Pleistocene. These weathering events are most likely associated with favorable conditions that combine (i) wet climate displaying sufficient meteoric water/fluid; and (ii) regional exhumation, due to large-scale vertical lithospheric movements enhancing the percolation of fluids. Matched with previous works, these results refine the stratigraphic frame for the polymetallic mineralization and clay deposits in the district, confirming the influence of meteoric fluids circulation during the late Cenozoic. As a consequence of the new (U-Th)/He data, we moreover propose a taxo...
During the early Cretaceous, successive tectonic phases and several sea level falls resulted in t... more During the early Cretaceous, successive tectonic phases and several sea level falls resulted in the emersion of the main part of western Europe and the development of thick “lateritic” weathering. This long period of continental evolution ended with the Upper Cretaceous transgressions. During this period, the exposed lands displayed a mosaic of diverse morphologies and weathered landscapes. Bauxites are the most spectacular paleoweathering features, known for long in southern France. Recently, new residual outcrops have been identified, trapped in the karstic depressions of the Grands Causses. Other bauxitic formations, containing gibbsite, have also been recognised, occurring with the Clay-with-Jurassic-cherts in the southeastern border of the Paris Basin. These bauxitic formations overlay Jurassic limestone and are buried beneath Upper Cretaceous marine deposits. The recognition of bauxites up north into the southern Paris Basin significantly widens the extension of the Lower Cret...
Data Revues 16310683 Unassign S1631068310001703, 2011
European terrestrial vertebrate sites of the Upper Paleocene–Lower Eocene deposits are predominan... more European terrestrial vertebrate sites of the Upper Paleocene–Lower Eocene deposits are predominantly known from the central and eastern parts of the Paris Basin. However, several outcrops covering this interval are scattered along the Upper Normandy coast, in the western part of the Paris Basin. Here we report the discovery of a new terrestrial vertebrate site in the Mortemer Formation, at the top of the cliffs of Sotteville-sur-Mer in Upper Normandy, France. The vertebrate level is situated about 1.5 m above the onset of the ...
The geological archives record" hyperthermic" crises, along with their consequences on ... more The geological archives record" hyperthermic" crises, along with their consequences on the biota and physical environment. Among these, the PETM (Paleocene-Eocene Thermal Maximum) is often considered as the closest analogue to the current climate crisis due to ...
ABSTRACT The earliest Eocene Erquelinnes site was discovered in 1880, but its mammal fauna has be... more ABSTRACT The earliest Eocene Erquelinnes site was discovered in 1880, but its mammal fauna has been frequently ignored. This paper provides the first detailed overview of the Erquelinnes mammals since 1929. The new faunal list doubles the known diversity at Erquelinnes to a total of 16 species, now also including amphilemurids, hyaenodontids, mesonychids, louisinids, equids and diacodexeids. The majority of the Erquelinnes species is also present in the earliest Eocene Dormaal MP7 reference fauna, with as most notable exceptions the presence of a potentially dwarfed specimen of Dissacus, and of two perissodactyl taxa at Erquelinnes. The ceratomorph perissodactyl Cymbalophus cuniculus is also known from the earliest Eocene of England, but a specimen identified as cf. Sifrhippus sandrae is closely similar to contemporaneous primitive North American equids. This specimen represents the oldest unambiguous European equid and highlights faunal similarities between Europe and North America during this time interval. Faunal differences between Erquelinnes and Dormaal seem mostly due to depositional differences, and the Erquelinnes fauna represents a typical earliest Eocene fauna, closely similar to other MP7 and PEI faunas in Europe.
The late Palaeocene carbon isotope excursion (C.I.E.) is often regarded as the best means of corr... more The late Palaeocene carbon isotope excursion (C.I.E.) is often regarded as the best means of correlating marine and continental deposits. The few isotopic studies carried out in continental environments were based on pedogenic carbonate [Koch et al., 1992], or on organic matter. Sinha [1997] took up this subject starting from the outcrops on the coast of the English Channel at Varangeville, where marine sequences biostratigraphically constrain the isotopic excursion. His work documents a negative delta 13 C org excursion value approximately -27 per mil PDB. The present work points out that it is necessary to study more complete sections than those studied by Sinha. A section named Phare d'Ailly has been sampled in detail (figs. 1, 2, 3). In this section, for which detailed analysis of sedimentology, palaeontology and organic matter facies establish the continental nature of the palaeoenvironment, isotopic analysis of organic matter reveals a very negative delta 13 C org excursio...
The mining district of Nefza-Sejnane (Tunisia) encloses numerous ores and raw material deposits, ... more The mining district of Nefza-Sejnane (Tunisia) encloses numerous ores and raw material deposits, all formed in relation with successive Fe-rich fluids of meteoric and/or hydrothermal origins. Here, for the first time in Tunisia, (U-Th)/He ages were obtained on supergene goethite from various localities/deposits of the district highlight direct dating of significant weathering episodes during late Tortonian and late Pleistocene. These weathering events are most likely associated with favorable conditions that combine (i) wet climate displaying sufficient meteoric water/fluid; and (ii) regional exhumation, due to large-scale vertical lithospheric movements enhancing the percolation of fluids. Matched with previous works, these results refine the stratigraphic frame for the polymetallic mineralization and clay deposits in the district, confirming the influence of meteoric fluids circulation during the late Cenozoic. As a consequence of the new (U-Th)/He data, we moreover propose a taxo...
During the early Cretaceous, successive tectonic phases and several sea level falls resulted in t... more During the early Cretaceous, successive tectonic phases and several sea level falls resulted in the emersion of the main part of western Europe and the development of thick “lateritic” weathering. This long period of continental evolution ended with the Upper Cretaceous transgressions. During this period, the exposed lands displayed a mosaic of diverse morphologies and weathered landscapes. Bauxites are the most spectacular paleoweathering features, known for long in southern France. Recently, new residual outcrops have been identified, trapped in the karstic depressions of the Grands Causses. Other bauxitic formations, containing gibbsite, have also been recognised, occurring with the Clay-with-Jurassic-cherts in the southeastern border of the Paris Basin. These bauxitic formations overlay Jurassic limestone and are buried beneath Upper Cretaceous marine deposits. The recognition of bauxites up north into the southern Paris Basin significantly widens the extension of the Lower Cret...
Data Revues 16310683 Unassign S1631068310001703, 2011
European terrestrial vertebrate sites of the Upper Paleocene–Lower Eocene deposits are predominan... more European terrestrial vertebrate sites of the Upper Paleocene–Lower Eocene deposits are predominantly known from the central and eastern parts of the Paris Basin. However, several outcrops covering this interval are scattered along the Upper Normandy coast, in the western part of the Paris Basin. Here we report the discovery of a new terrestrial vertebrate site in the Mortemer Formation, at the top of the cliffs of Sotteville-sur-Mer in Upper Normandy, France. The vertebrate level is situated about 1.5 m above the onset of the ...
The geological archives record" hyperthermic" crises, along with their consequences on ... more The geological archives record" hyperthermic" crises, along with their consequences on the biota and physical environment. Among these, the PETM (Paleocene-Eocene Thermal Maximum) is often considered as the closest analogue to the current climate crisis due to ...
ABSTRACT The earliest Eocene Erquelinnes site was discovered in 1880, but its mammal fauna has be... more ABSTRACT The earliest Eocene Erquelinnes site was discovered in 1880, but its mammal fauna has been frequently ignored. This paper provides the first detailed overview of the Erquelinnes mammals since 1929. The new faunal list doubles the known diversity at Erquelinnes to a total of 16 species, now also including amphilemurids, hyaenodontids, mesonychids, louisinids, equids and diacodexeids. The majority of the Erquelinnes species is also present in the earliest Eocene Dormaal MP7 reference fauna, with as most notable exceptions the presence of a potentially dwarfed specimen of Dissacus, and of two perissodactyl taxa at Erquelinnes. The ceratomorph perissodactyl Cymbalophus cuniculus is also known from the earliest Eocene of England, but a specimen identified as cf. Sifrhippus sandrae is closely similar to contemporaneous primitive North American equids. This specimen represents the oldest unambiguous European equid and highlights faunal similarities between Europe and North America during this time interval. Faunal differences between Erquelinnes and Dormaal seem mostly due to depositional differences, and the Erquelinnes fauna represents a typical earliest Eocene fauna, closely similar to other MP7 and PEI faunas in Europe.
The late Palaeocene carbon isotope excursion (C.I.E.) is often regarded as the best means of corr... more The late Palaeocene carbon isotope excursion (C.I.E.) is often regarded as the best means of correlating marine and continental deposits. The few isotopic studies carried out in continental environments were based on pedogenic carbonate [Koch et al., 1992], or on organic matter. Sinha [1997] took up this subject starting from the outcrops on the coast of the English Channel at Varangeville, where marine sequences biostratigraphically constrain the isotopic excursion. His work documents a negative delta 13 C org excursion value approximately -27 per mil PDB. The present work points out that it is necessary to study more complete sections than those studied by Sinha. A section named Phare d'Ailly has been sampled in detail (figs. 1, 2, 3). In this section, for which detailed analysis of sedimentology, palaeontology and organic matter facies establish the continental nature of the palaeoenvironment, isotopic analysis of organic matter reveals a very negative delta 13 C org excursio...
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